Acute atrial fibrillation (AAF) in cardiac surgery postoperative period: evaluation of pre- and perioperative factors associated with its higher incidence

Propranolol plasma levels and pharmacokinetics (PK) may be altered by cardiopulmonary bypass (CPB). Propranolol kinetic disposition was investigated in patients submitted to myocardial revascularization with mild hypothermic cardiopulmonary bypass (HCPB).

Background: Treadmill stress test (TST) is an easily available, inexpensive and well-studied tool for the diagnosis of coronary artery disease. However, very few studies have been done to determine the prognostic value of TST in patients seen in the emergency room with chest pain and unclear diagnosis. Population and method: We prospectively studied 22 consecutive patients admitted to our Coronary Care Unit between October 1997 and December 1997, and who had at least two CRP measurements. Admission and highest values were selected for statistical analyses. Follow up was made through phone calls to patients, relatives or assistant physicians, and end-points were death or readmission due to cardiovascular events. Patients were divided in two subgroups according to a CRP level cutoff ≤1 mg%. Survival free of events was analyzed by Kaplan-Meyer method, and log-rank test was applied for comparison between curves.
Results: See Table. Conclusion: Elevated CRP levels in patients admitted due to unstable angina can predict cardiovascular prognosis during a 2-year follow up. As only highest values correlated with worst outcomes, it seems reasonable that two or more measurements should be done during hospitalization. Results: There were 15 patients in group A and 24 in group B. There were no statistical differences between following variables: age, gender and ventricular function. There were statistical differences between the following variables: shock -group A 53.3%, Group B 87% (P = 0.017); and surgical treatment -group A 80%, group B 41.6% (P = 0.019). In the surgical subgroup we found preoperative IABP implantation in 83.3% of group A patients and 30% of group B patients (P = 0.016). Analyzing group B, we found four out of 14 patients in percutaneous subgroup treatment with favorable coronary anatomy for heart surgery that was not performed by clinical decision; four out of 10 in surgical subgroup treatment had Duke University Criteria of preoperative IABP implantation that was not performed by surgical staff decision.
Discussion: This small retrospective study suggests the importance of preoperative IABP implantation in high-risk patient and one advantage for IABP impact in mortality for surgical strategy. Objectives: To analyze the incidence of hemorrhagic complications related to interventional coronary percutaneous procedures and associations with different variables: interventional techniques, demographic data and pharmacological adjuvant treatment.

Materials and method:
A total of 270 patients (183 men and 87 women, mean age 62.6 ± 12.5 years and 71.8 ± 10.6, respectively; P < 0.00001) underwent 270 percutaneous coronary proce-dures. The following data were registered and correlated to vascular complications: diagnostic coronary angiography, percutaneous coronary angioplasty (PTCA), clinical features (diagnosis, coronary risk factors), antithrombotic therapy, activated coagulation time (ACT), sheath diameter and manipulation of puncture site.
Results: There were 45.7% with a diagnosis of unstable angina, 40.8% with acute myocardial infarction and 11.3% with stable angina. Smoking was observed in 49% of men and 19% of women (P = 0.001). No significant statistical differences were observed in relation to other variables. Incidence of hematomas (HMT) was higher among women before (P = 0.01) and after (P = 0.04) sheath removal, associated with higher platelet depletion (P = 0.004) and higher heparin dose (HD; P = 0.04), but not with hemoglobin reduction (P = 0.08). Among patients with HMT, HD was higher (P = 0.04), stents were more used (P = 0.02), larger sheaths (P = 0.015), and more prolonged initial ACT (P = 0.04), sheath maintenance (P = 0.005), ASA (P = 0.04) and ticlopidine therapy (P = 0.003), and hemodynamic instability (HI; P = 0.005). There was no correlation between abciximab and HMT.
Conclusion: Higher incidence of HMT was detected among women and was associated with older age, higher HD, higher Hb and platelet depletions, larger sheath diameter, larger time of sheath maintenance, use of ASA/ticlopidine, ACT and HI. Initial diagnosis, risk factors, procedure duration and use of abciximab did not correlate with HMT. Objective: Despite the high incidence of cardiac arrest (CA) in ICU, this situation is poorly notified and analyzed, not only in ICU but also in other clinics. Most registrations refer to out-of-hospital or emergency units CA and their causes, initial rhythm and prognosis are very distinct from CA in ICU. Ultstein method is a model of CA notification recommended by American Heart Association (AHA) and Brazilian Society of Cardiology. Our objective is to describe the first results of Ultstein method in our ICU.
Methods: Ultstein forms notifying CA between April 1999 and January 2000 were analyzed. Doctors or nurses involved in the resuscitation efforts filled out the forms.

Conclusion:
Intrahospital CA notification is important to allow a comparison with those that occur outside the hospital. Moreover, it allows us to know how CA is managed and how we can optimize the patient assistance. Background: The emergency unit is a scenario of the development in cardio-preventive strategies, and emergency professionals should be prepared to instruct patients as to the early signals and symptoms of such diseases. We should take advantage of this opportunity window to initiate an educational strategy aiming the early identification and significance of these warning signals, as well as the likely procedures and diagnostic examinations that may be carried out during the in-hospital period, focusing on the patient's better satisfaction and understanding.

Objective:
To evaluate the quality of the information provided to the client under observation in the chest pain unit.

Materials and method:
This is a pilot study in which an educational video tape about AMI presenting early signals and symptoms, diagnostic examinations and healthy life habits. The video tape was shown to 20 clients under observation in the Chest Pain Unit and afterwards a questionnaire was provided.
Results: A total of 20 patients were interviewed; 60% (n = 12) were male and 40% (n = 8) female; 100% (n = 20) considered that the explanation on the video was clear and met their expectations; 35% (n = 7) would like to obtain further information besides that provided; and 55% (n = 11) felt less apprehensive and 5% (n = 1) felt more apprehensive.

Conclusion:
The educational strategy by means of audiovisual resource has been implemented and evaluated in developed countries. Implementing and evaluating this strategy in Latin American countries, where we find great sociocultural discrepancy, has been a challenge in the effort to improve the contentment of the patient admitted to emergency units.

P18 Basic life support education for first year health students at UNISUL J Andrade, NO Nazário, E Pizzichini, NW Luz Universidade do Sul de Santa Catarina, Tubarão, Brazil
Background: In Brazilian medical schools a basic life support (BLS) education curriculum is a rarely found through the graduate period. When it exists, length of training is very short and limited to theoretical contents. Besides, for the first 2 or 3 years medical education is exclusively directed to basic science.
Objective: To implement a BLS educational program for dentistry and medical school, based on theoretical/practical approach following the American Heart Association standards for BLS training.
Design: A 60-h course was designed encompassing BLS and basic care of trauma patients. The contents are divided in theory and practice in a balanced basis. BLS contents are developed in 12 h including adult, children and babies. Appropriated manikins are used for each scenario.
Setting: Cardiopulmonary resuscitation laboratory at Universidade do Sul de Santa Catarina.
Subjects: Medical and dentistry first-year students.
Experience: For the last 2 years we have developed this program with a very intense participation of most students. Dentistry alumni have also demonstrated interest and an excellent performance.
Main results: We found a great deal of enthusiasm among most of our students and many of then have been working as volunteer educators of BLS for high school students in another program linked to this experience. Through this time we have concluded that this idea is feasible and stimulating as it brings the students to a useful content for them and the community where they live.

Conclusion:
A BLS education program for dentistry and medical school first-year students is viable and should be put into practice in other universities and in many other countries.

P19 GRACE (the Global Registry of Acute Coronary Events): the real world side of the cardiovascular clinical practice in acute coronary syndromes M Knobel, A Avezum, R Kaneko, AC Baruzzi, E Knobel Hospital Israelita Albert Einstein -CTI, São Paulo, Brazil
Introduction: Data on clinical efficacy can be obtained from randomized trials; however, data truly reflecting the clinical practice on acute coronary syndromes (ACS) may only be acquired through registries.
Objectives: To collect, analyze and disseminate data on the ACS management during the hospital phase, and to evaluate the causes of suboptimal outcomes for improving health care.
Method: GRACE is an multinational, prospective, cross-sectional study, conducted in 14 countries (three continents), evaluating demography, treatment, diagnosis, procedures and outcomes in ACS patients.
Results: See Table. Conclusion: There were higher proportions of female patients in Brazil and World groups, a higher proportion of patients in the STEMI group received aspirin, fewer patients received β-blocker in the UA group at HIAE, and more patients received LMWH, cardiac catheterization and PCI at HIAE. Also, there were substantial differences in the treatments, procedures, and death rates among the three ACS. Based on these preliminary results we may optimize the clinical practice aiming at improving cardiovascular outcomes. There is a growing interest in the pathophysiology of processes involving vascular cell injury and redox signaling, particularly with superoxide generation. Lucigenin chemiluminescence has been extensively used as a method to assess superoxide production and its underlying enzymatic mechanisms in many biological systems, the most studied one being the vascular NAD(P)H oxidase. Recent evidence suggests substantial limitations of this probe because of artifactual superoxide generation. To investigate if lucigenin concentration could affect the detection of vascular NAD(P)H oxidase activity we performed studies with lucigenin chemiluminescence, oxygen consumption and electron paramagnetic resonance (EPR) spectroscopy for superoxide generation detection with vascular homogenates and different concentrations of lucigenin (5, 50 and 250 µM). The NAD(P)H oxidase blocker diphenylene iodonium (DPI, 20 µM), SOD (500 IU/ml), catalase (500 IU/ml) and the electron acceptor NBT were also used to characterize lucigenin behavior in a vascular system.
Our data showed that lucigenin alone, with 5 µM, induced a 2-fold increase in oxygen consumption, while with 250 µM oxygen consumption increased 5-fold. Superoxide generation, assessed by EPR spectroscopy, also increased progressively with 5, 50 and 250 µM lucigenin. These effects were particularly enhanced by addition of NADH, but occurred also with NADPH. Chemiluminescence studies showed that with 5 and 50 µM lucigenin there is greater NADPH induced signal than NADH, while 250 µM lucigenin yields a 1.5-fold greater signal with NADH than with NADPH. Furthermore, all NADPH-driven luminescent signals were inhibited by SOD, DPI, and NBT, as well as NADH-driven luminescence with 5 µM lucigenin. On the other hand, with lucigenin 250 µM, NADH-driven luminescence could not be blocked by SOD or DPI, but was completely inhibited by NBT. Catalase did not show any inhibitory effect on NADPH-induced luminescence, but inhibited 30% of NADH-driven signals.
In conclusion, lucigenin even at low doses undergoes redoxcycling reactions, which are favored by NADH generating artifactual superoxide. Furthermore, it is possible that lucigenin acts as a direct electron acceptor from vascular enzymatic sources other than the superoxide-generating NAD(P)H oxidase, and detects also hydrogen peroxide generated by a vascular NADH oxidase. The inflammatory response that occurs in sepsis has been related to the presence of cytokines, and also other soluble factors such as fas and fas-l, which can induce apoptotic cell death of endothelial cells. Also, it can result in endothelial dysfunction, with microvascular thrombosis and activation of the coagulation cascade. These events involve the transduction of extracellular stimuli by reactive oxygen species (ROS; O 2 •-, H 2 O 2 ) that result in activation of intracellular signaling pathways like MAPKinases. We sought to evaluate the effect of soluble factors present in plasma of septic patients in rabbit endothelial (REC) and vascular smooth muscle cells (RASM) in culture, by assaying for apoptosis with a TUNEL detection method. Also, we assessed NAD(P)H oxidase production of ROS in these plasma samples and in REC and RASM homogenates after incubation with plasma, as assessed with the lucigenin 5 µM chemiluminescence technique.

P21 Macrophage migration inhibitory factor (MIF), C-reactive protein (CRP) and
Septic plasma showed ROS generation when incubated with NADPH but not with NADH (51.44 ± 21.18 and 8.90 ± 4.04 versus 7.77 ± 2.60 and 1.8 ± 0.99 cpm × 10 3 /mg/min, NADPH and NADH versus controls, respectively; n = 5-3). When incubated with homogenates of REC or RASM in the presence of both NADH or NADPH, septic plasma caused a 2-to 3-fold increase in ROS generation versus healthy control plasma (n = 5-3). Thus, septic plasma lead to apoptosis of REC and RASM, abrogated by a SOD mimic and NAD(P)H oxidase inhibitor DPI. Intrinsic NADPH oxidase ROS production was detected in the septic plasma. It also enhanced the NAD(P)H oxidase ROS production in REC and RASM homogenates. These data suggest that in sepsis there is a possible link between ROS production and vascular cell apoptosis. Methods: Under general anesthesia using etomidate and isoflurane, and with controlled ventilation, 2 animals were submitted to progressive ANH with either hydroxyethyl starch (HES, n = 10) or Ringer's lactate (RL, n = 10) solution on a ratio of 1:1 or 1:3, respectively. A Swan-Ganz catheter, echocardiography and eletrocardiography were used in the assessment of the cardiovascular function. The hemodilution was monitored with sequential measurements (20 min) of the concentration values of hemoglobin and hematocrit, while the cardiovascular function for the different variables were studied. Data were evaluated through ANOVA (P < 0.05).

Results:
The final hemoglobin concentration for the HES was 4.0 (± 1.2) g/dl and 3.0 (± 1.0) g/dl for the RL. Heart rate and blood pressure did not change. The cardiac output and cardiac index increased in both groups during the hemodilution procedure; however, the RL group data had a lower value than was statistically significant at the end of the study period. The systemic and pulmonary vascular resistance decreased in both groups. The pulmonary capillary wedge pressure and central venous pressure reached higher values in both groups during ANH.

Conclusion:
The study demonstrated that the cardiovascular variables deteriorated along with the reduction hemoglobin; nevertheless, the echocardiography data obtained would suggest that the use of HES allowed better cardiac contractility during prolonged periods of time over in lower levels of hemoglobin.

P24 Role of biocompatible IV infusion pumps in hemodynamic instability D Moura Jr, M Oliveira, A Gibertoni Jr, L Silva, A Ferreira, M Cendoroglo, E Knobel Centro de Terapia Intensiva do Hospital Israelita Albert Einstein, São Paulo, Brazil
Biocompatibility is defined as the ability of a material or equipment to perform without inducing a clinically significant response. We started using an IV infusion pump calibrator (BIOTECH) in 1999 for quality control. Very soon we observed that some peristaltic IV pumps presented with a phasic variation of flow, although the average flow was well calibrated (and used to be categorized as so). Theoretically, this could have a clinically significant impact in the delivery of vasoactive drugs with fast and short action, such as nitroprusside or norepinephrine. We tested three different brands of pumps, two peristaltic (A, n = 10; and B, n = 13) and one syringe pump (C, n = 5) at a flow of 50 ml/min for 20 min. The average flow was 48.5 ± 3.4 ml/min, 51.6 ± 0.4 ml/min and 52.6 ± 2.0 ml/min, respectively (P < 0.001).
During the 20 min of observation, the number of phases (plus and minus peaks) was 13.2 ± 2.5, 8.9 ± 4.5 and 16.8 ± 3.0, respectively (P = 0.002). Therefore, pump type B had the highest variation with phases that lasted longer. The most extreme case was a type B pump, which showed a 32% variation in flow (from 62 to 46 ml/min) with plateaus lasting for up to 4 min and 27 s. In conclusion, IV infusion pumps may have phasic flow variations with long-lasting plateaus that could have an impact on the delivery of vasoactive drugs, possibly worsening hemodynamic instability. Introduction: We recently observed, using an orthogonal polarization spectral (OPS) imaging device, that microvascular blood flow is altered in patients with sepsis. We hypothesized that these alterations may be reversed by acetylcholine (ACH).

Methods:
We used an OPS device (Cytoscan A/RII; Cytometrics, Philadelphia, USA) with a 5× magnitude to explore the sublingual area in 11 patients with septic shock and 10 healthy volunteers. In each case, five sublingual areas were recorded for later analysis. Septic patients also received topical application of ACH 10 -2 M. Five representative sequences of 20 s were analyzed semiquantitatively: vessel density was defined as the number of vessels crossing three horizontal and three vertical lines; flow was defined as continuous, intermittent, and absent. The vessels were then separated into venules and capillaries using a 20 µm cutoff value. Data from the five areas were averaged and analyzed by Kruskall-Wallis and Wilcoxon tests. Data are presented as median (percentiles 25-75).
Results: See Table. Conclusions: Microcirculatory alterations in patients with septic shock can be reversed by topical ACH, suggesting that these alterations are primarily due to an increased vasomotor tone. Interventions: Animals were infected through intravenous (iv) or intraperitoneal (ip) injections of Escherichia coli in the following concentrations LD 0 , LD 50 and LD 100 , while control animals received no intervention prior to sacrifice. Samples of peritoneal exudate were obtained at 4, 8, 12 and 24 h intervals after inoculation and submitted to flow cytometry analysis.

Division of Infectious Diseases, UNIFESP, São Paulo, Brazil
Background: Underlying disease (UD) is an important variable associated with outcome in sepsis, but its role in inflammatory response has not been evaluated.

Methods:
We studied the ability of LPS and killed Gram-negative bacteria (GNB) to induce TNF-α and IL-10, and of PHA to induce IFN-γ, in whole blood from septic patients (n = 20), patients with matched UD and without sepsis (n = 20), and healthy volunteers (n = 20).

Main results and conclusions:
We found a decreased production of TNF-α and IFN-γ in septic patients, while the production of IL-10 was not different in the three groups. Production of IFN-γ and TNF-α in whole blood from patients without sepsis were higher than in septic patients, yet lower than in healthy controls. Downregulation of TNF-α production in septic patients, although not restricted to, was more pronounced with LPS than with GNB. Infection itself and UD are involved in the regulatory mechanisms of inflammatory response. Background: The use of whole blood (WB) for studying the LPSinduced cellular activation preserves the milieu in which LPS-cell interaction occurs in vivo. However, information at single-cell level using this system is lacking. In this study we evaluated the LPS-binding, internalization, and cell activation, in WB, using flow cytometry. The influence of heparin or EDTA as anticoagulant was also addressed.
Method: Blood samples were obtained from healthy donors in EDTA and/or heparin tubes. Biotinilated LPS (LPSb) was used to evaluate cell binding and internalization of LPS in WB. Cells were surface stained with appropriate antibodies and LPSb was detected by the addition of streptavidin-red 670 or -APC. LPSinduced cell activation was evaluated by expression of surface activation markers and detection of intracellular TNF-α.

Results:
LPSb bound promptly to monocytes. In EDTA-treated blood membrane-bound LPSb decreased after 60 min of incubation, reaching background levels after 240 min. In contrast, membrane-bound LPSb remained detectable in heparinized blood in a high proportion of the cells. LPS induced TNF-α and enhanced the expression of HLA-DR in monocytes, and induced the expression of CD69 in T and B lymphocytes. Induction of TNF-α in monocytes and, to a lesser degree of CD69 in lymphocytes, was more efficient in heparinized-blood. interferon-γ) are postulated to play a major role in the pathogenesis of the syndrome. A lot of study show that the presence of circulating cytokines has been found in patients with documented bacteremia or with signs of sepsis, often correlating with the severity of disease. The aim of the present study was to measure these inflammatory mediators (TNF-α, IL-6, IL-10 and nitric oxide) in different phases of septic patients, polytrauma and health volunteers to demonstrate that these mediators play a role in the pathogenesis of sepsis but do not serve as a prognostic marker.

Methods:
Patients: the study sample included 19 patients with pulmonary sepsis; eight critically ill patients suffering from major tissue injury due to polytrauma, admitted in the medical intensive care unit; and 16 healthy controls. The criteria for inclusion in the group with sepsis were according to criteria of American College of Chest Physicians/Society of Critical Care Medicine Consensus. All septic patients were monitored using a pulmonary artery catheter (93A-431-75F Baxter) and the sepsis phases were separated using the hemodynamic criteria. This study was approved by the ethical council of the Hospital. Informed consent was obtained from all patients or next-of-kin. The samples were obtained in the Hospital Municipal Miguel Couto and the Hospital Universitário Clementino Fraga Filho (HUCFF).

Measurements and main results:
We found an early and intense growth in peritoneal cell population following ip injury. Granulocytes are the predominant cells in this process and correlate with mortality. LD 100 group shows a reduction in this population at 12 and 24 h. There is an absolute and relative reduction in the macrophage cell population at 4, 8, 12 and 24 h. Following iv injury, peritoneal residents cell pattern does not suffer major modification, except for the 24 h LD 0 group, in which granulocytes and lymphocytes increase and macrophages decrease.

Conclusions:
This model suggests that, following E coli peritoneal challenge in mice, when a marked and maintained grow in the gralulocyte population occurs, it is associated with survival. Also, a reduction on the migration of this population, or its destruction, indicates uncontrolled systemic inflammation and death. Macrophage migration would be linked to the initiation of the specific immune response, and its population is not correlated with survival outcome. Introduction: The identification of the early steps of the response trigged by free DNAs on normal cells may elucidate questions concerning the pathophysiology of some diseases. Small amounts of plasma free DNA have been observed both in healthy individuals and in patients with various diseases such as systemic lupus erythematosus, viral hepatitis and cancer. This study demonstrates that septic patients also release DNA in plasma at levels higher than polytraumatic patients, who also have an inflammatory response to trauma. In vitro studies of protein profile of normal leukocytes in response to a short exposure to DNA purified of bacteria, protozoa (T cruzi), human DNA (HeLa cells) and to a synthetic unmethylated CpG motif, demonstrated that free DNA is able to modify the protein profile of the blood cells. Understanding how free DNA act as a signal between cells is important for knowing how DNA orchestrates immune responses in sepsis and other diseases. The role of lipopolysaccharide in the physiopathology of sepsis is clearly recognized, but additional effort will be needed to clarify the sepsis puzzle. Plasma DNA purification: DNA was extracted from plasma by a method adapted from Federov et al [1] and amplified by PCR of Kras. Quantification of the amount of DNA was estimated with ethidium bromide fluorescence.

Results:
We noted that there were no difference in the measurements of interleukin in the different phases of septic patients and no difference with the polytrauma group and the healthy volunteers. There were no correlations with release of interleukin and the antibiotic used in septic patients. The only measurement that had correlation with the severity of the sepsis was the IL-6, in the phase D that corresponds with septic shock.

Conclusion:
Our findings contradict those from a number of earlier studies that correlated severity of sepsis and plasma levels of cytokines. Moreover, the chances of detecting elevated cytokine levels during severe infections are limited by their half -lives. Both TNF and IL-6 may decline despite persistence or even increased severity sepsis. When cytokines were first discovered, it was generally assumed that their presence in the circulation signaled pathology. As we noted, there is a considerable interindividual variation in cytokine production. Age, gender, or pre-existing disease could be the explanation of these variations. Despite cytokines play a role in the pathogenesis of sepsis, their measurement does not serve as a marker of infection disease and does not discriminate the severity of the inflammatory infectious response.

Results:
Results are expressed as mean ± SD (Table). Introduction and objective: Intraoperative acute isovolemic hemodilution has been used to decrease the need for homologous blood transfusion. Decreased arterial oxygen content and total oxygen delivery to tissues promote a compensatory increase in cardiac output, related to the hemodilution-induced decrease in viscosity and/or vasodilatation, preserving tissue oxygen delivery. Regional blood flow distribution may vary widely between and within organs. Splanchnic hypoperfusion, particularly at the intestinal mucosal region, has been implicated in systemic inflammatory response and multiple organ dysfunction. We evaluated systemic and splanchnic oxygen-derived variables during a moderate acute isovolemic hemodilution to test the hypothesis that hemodilution may promote gastric mucosal acidosis, despite an apparent adequacy of global markers of oxygen delivery and consumption.
Methods: Eleven anesthetized mongrel dogs (16.7 ± 0.8 kg) were monitored with a Swan-Ganz catheter (cardiac output, cardiac filling pressures, mixed venous blood samples and lactate), an aortic catheter (mean arterial pressure and blood sampling), a portal vein catheter (portal lactate and blood gas), transit time ultra-sonic flow probe (SMA blood flow) and a gas tonometer (PgCO 2 and PCO 2 gap). The animals were randomly assigned into two groups: controls (CT), no hemodilution; and acute isovolemic hemodilution (HD), induced by blood withdrawal (20 ml/min) with a simultaneous infusion of hydroxyethyl starch 6% in saline solution to a target hematocrit of 25 ± 3% for 30 min. The animals were then followed for 60 min.
Results: Hemodilution promoted significant decreases in hemoglobin, hematocrit, and pulmonary and systemic vascular resistances, and significant increases in cardiac output and in SMA blood flow. No significant differences between groups were detected on mean arterial and pulmonary artery pressures, oxygen delivery and extraction, PCO 2 gap, and systemic and portal vein PCO 2 , pH and lactate.

Conclusion:
Moderate isovolemic hemodilution induced decreases in hemoglobin and hematocrit; however, the associated compensatory increases in cardiac output and regional blood flows prevented splanchnic hypoperfusion in this experimental model. Introduction: Prehospital fluid resuscitation, before hemorrhage control, of hypotensive trauma victims sustaining blunt or penetrating abdominal trauma is highly controversial, largely due to concerns related to increased blood loss or rebleeding.

Objective:
In two separate studies, simulating blunt or penetrating abdominal trauma, we tested the hypothesis that prehospital fluid resuscitation could provide hemodynamic benefits despite increased intra-abdominal bleeding, which was directly measured after a spleen rupture or an iliac artery tear.

Conclusion:
No fluid infusion during intra-abdominal bleeding resulted in a low blood flow state, while resuscitation with both HSD and LR produced hemodynamic benefits without increased blood loss.

Figure
Conclusion: Noradrenaline requirement >0.3µg/kg/min is associated with high mortality in SS. Based on these results, a new and strong cri-terium for severe septic shock is proposed. We also showed the feasibility of applying a predefined algorithm for hemodynamic treatment. It has been suggested that PMN apoptosis is increased in dialysis patients and may contribute to cellular dysfunction. We investigated the effect of treatment modality and biochemical parameters on PMN apoptosis and function. Blood was drawn from 17 controls, 17 patients with chronic renal failure (CRF; creatinine clearance 28 ± 14 ml/min/1.73m 2 ), 10 hemodialysis (HD) and 11 CAPD patients. Upon collection, whole blood aliquots were incubated in RPMI-1640 with propidium iodide (PI)-labeled S aureus (SA), PMA, fMLP or LPS for 30 min. Cells were then stained with DCFH-DA and analyzed by flow cytometry, in order to quantify phagocytosis and H 2 O 2 release by PMN. After separation by gradient centrifugation, PMN were stained with Annexin-V and PI in order to quantify apoptosis by flow cytome-try. The results were correlated with blood levels of urea, creatinine, bicarbonate, albumin and PTH. Results are presented as means ± SD.

NEPHROLOGY P34 Impact of treatment modality, biochemical parameters and apoptosis on polymorphonuclear cell (PMN) function in
Among CRF and HD patients, there was an inverse correlation between apoptosis and SA-(r = 0.62, P = 0.01 and r = 0.89, P = 0.02, respectively) and LPS-stimulated H 2 O 2 release (r = 0.68, P = 0.005 and r = 0.61, P = 0.058, respectively). No biochemical parameters correlated with apoptosis or cellular functions. In summary, PMN apoptosis contributes to cellular malfunction in uremia, but does not account for all the dysfunction. Hence, it is possible that other uremic toxins affect cell performance independently of apoptosis.  In 1997, we started performing CVVH/HD in our ICU, which allowed us to improve the metabolic control of our dialysis patients. We sought to investigate the trends in mortality rates of ARF patients treated in our ICU from January 1992 to December 1998. The APACHE II score and risk of death of all patients (n = 10723, age 61 ± 18 years, 62% males) and of patients with ARF submitted to dialysis therapies (n = 256, age 61 ± 18 years, 70% males) are shown in the Table. In 1998, for the first time, the mortality in the ARF population was lower than the expected mortality (risk of death). Comparing the 1992-1996 period with 1997-1998, there was no reduction in the expected mortality (49% versus 44%; P = 0.46), but there was a significant reduction in the ICU mortality (62% versus 48%; P = 0.04). This improvement in survival could be due to an overall improvement in our standards of care or in the dialytic therapy. The aim of this study was to investigate the impact of the addition of calcium to bicarbonate solutions for CRRT. We tested single bag (SB; bicarbonate and calcium mixed 24 h before testing) and double bag (DB) solutions (mixed immediately before), with and without the addition of 4 mEq/l acetate. Prescribed calcium varied from 0-5 mEq/l. In all test solutions prepared with calcium 5 mEq/l there was a decrease in the measured calcium concentration. SB solutions presented lower concentrations of calcium, compared with DB solutions. When the prescribed calcium concentration was increased, there was a parallel increase in calcium deficit (prescribed-measured). The prescribed calcium showed a negative cor-relation with sodium and potassium and a positive correlation with pCO 2 . We also found a positive correlation between calcium deficit and pCO 2 (r = + 0.59; P < 0.001). The crystallization, as measured by the weight of the crystals, was greater in the SB solutions when compared to the DB solutions (17.7 ± 7.0 mg versus 9.1 ± 1.8 mg, n = 14; P = 0.01). The crystallization correlated with the measured concentration of calcium (r = -0.62; P = 0.02), and pCO 2 (r = + 0.75; P = 0.002). We also observed a negative correlation between the pH, and the pCO 2 (r = -0.82; P < 0.001). Our results suggest that the use of bicarbonate solutions containing calcium as replacement fluids for CRRT is a potentially unsafe procedure.

P38 Hypokalemic thyrotoxic periodic paralysis in intensive care unit (UCI) AC Seguro, FC Seguro ICU Hospital São José do Braz, São Paulo, Brazil
Hypokalemia with profound muscle weakness and respiratory failure may be occasionally found in intensive care unit (ICU) patients. Thyrotoxic periodic paralysis is a rare cause of this disturbance mainly seen in Asian patients. Hyperadrenergic activity with potassium shift from extracellular to intracellular medium has been implicated as the pathogenic mechanism. We report a patient who had thyrotoxic periodic paralysis diagnosed 7 years ago, and he has been followed until now. A 23-year-old white man presented to the emergency room with profound weakness and respiratory failure, the patient was moved to the ICU for ventilatory assistance. His blood pressure was 11 × 7 cmHg, heart rate 88 beats/min. The serum potassium was 1.5 mEq/l. He was treated with intravenous potassium chloride infusion and the symptoms progressively improved. He denied weight loss, palpitations and excessive perspiration. He was not taking diuretics or laxatives, or any drugs. His thyroid was diffusely enlarged. Laboratory investigation showed urinary potassium of 55 mEq/l, serum creatinine 0.5 mg/dl, fractional excretion of potassium 8.3%, glucose 88 mg/dl, magnesium 1.7 mg/dl, aldosterone 7.0 ng/dl, T3 382 ng/dl, T4 16.8 ng/dl, and TSH <0.03 mU/l. He was discharged on propylthiouracil 100 mg four times daily and propranolol 40 mg three times daily. Propranolol was withdrawn 2 months after, and propylthiouracil was maintained in reduced doses for 5 years when radioiodine therapy was performed. During 7 years of follow-up no recurrent episode of periodic paralysis was observed, confirming that hyperthyroidism was the cause of this episode. In conclusion, thyroid periodic paralysis may produce fatal complications; prompt recognition of this entity and therapy with KCl infusion and β-blockers to inhibit the intracellular shift of potassium are important to terminate acute attacks.

P36 Efficacy of hemodiafiltration on the outcome of renal and respiratory failure of leptospirosis LC Andrade, PCF Marotto, MS Marotto, J Sztajnbok, AC Seguro Instituto de Infectologia Emilio Ribas, Intensive Care Unit, São Paulo, Brazil
Introduction: A comparison between hemodiafiltration (HDF) and peritoneal dialysis (PD) was performed in patients with severe leptospirosis with acute renal failure and lung injury.

Conclusion:
The patients under HDF had a better metabolic control and oxygenation than those under HD. However, further studies will needed to show an impact on survival.

P39 Serial prognostic score indexes in acute renal failure (ARF): best performance of scores obtained at the time of referral to the nephrologist NMS Fernandes, M Cendoroglo, A Roque, PBP Batista, OFP Santos, RS Stella, S Draibe Division of Nephrology, Federal University of São Paulo, São Paulo, Brazil
The APACHE-II score has been validated for the time of admission at the ICU, but has been widely used in outcome studies of patients with ARF, and frequently obtained at the time of indication of dialysis. Another prognostic score index -the ATN-ISS -obtained at the time of referral to the nephrologist, seems to have a better performance than the APACHE-II score. We sought to investigate whether the time of collection of data for APACHE-II could influence its prognostic value, and to compare it with the more specific ATN-ISS score. In a historical prospective study, we collected data from 205 ARF patients at the Hospital São Paulo -a university-based, not-for-profit, tertiary hospital -between February 1997 and November 1997. APACHE-II scores were calculated at the time of hospital admission (AP-1), time of referral for the nephrologist (AP-2) and day of the first dialysis (AP3). The ATN-ISS score was also obtained at the time of referral to the nephrologist. There were 98 males and 107 females, with a mean age of 52 ± 18 years; 70 patients (34%) required dialysis and 68 patients (33%) were admitted to the ICU. The overall mortality rate was 46%. Nonsurvivors had higher AP1 (19.6 ± 8.7 versus 15.4 ± 6.0; P < 0.001), AP2 (23.4 ± 7.2 versus 16.7 ± 5.3; P < 0.001) and AP3 (25.8 ± 6.24 versus 20.3 ± 3.9; P < 0.001). ATN-ISS was also higher for nonsurvivors (0.81 ± 0.17 versus 0.26 ± 0.15; P < 0.001). The area under the receiver operator curve (AUC) was obtained for each score. The AUC was lower for AP1 than for AP2 (0.64 versus 0.76; P < 0.001). However, the AUC for AP2 was similar to the AUC for AP3 (0.78 and 0.77, respectively; P = 0.75). The ATN-ISS was a better predictor than AP2 (0.97 versus 0.76; P < 0.001). The better performance of scores at the time of referral to the nephrologist than scores obtained at the admission or at the day of first dialysis suggests that ARF per se may be an important determinant of prognosis.

P40 Use of APACHE-II as a prognostic score index for non-ICU patients with acute renal failure (ARF) NMS Fernandes, M Cendoroglo, P Suassuna, PBP Batista, C Balda, N Schor, SR Stella Division of Nephrology, Federal University of São Paulo, São Paulo, Brazil
The APACHE-II score has been used as an index of severity of illness for non-ICU patients with ARF in some studies. We sought to investigate the differences between ICU and non-ICU patients, and to determine whether APACHE-II can or cannot be used as a prognostic score index for non-ICU patients and to compare it with the ATN-ISS. To this end, we collected data from 205 ARF patients at the Hospital São Paulo -a university based, not-for-profit, tertiary hospital -between February 1997 and November 1997. APACHE-II scores were calculated at the time of hospital admission (AP-1) and time of referral to the nephrologist (AP-2). The ATN-ISS score was also obtained at the time of referral to the nephrologist. The period prevalence of ARF during the study was 1% (205/19524 admissions). There were 98 males and 107 females, with a mean age of 52 ± 18 years, and 70 patients (34%) required dialysis. Sixty-eight patients (33%) were admitted to the ICUs and 137 (67%) were treated in the wards or at the emergency ward. The overall mortality rate was 46%. In multivariate analysis, no differences were found between non-ICU and ICU patients for age, gender or oliguria. However, non-ICU patients had lower frequency of shock (25% versus 57%; P = 0.007) and mechanical ventilation (25% versus 60%; P = 0.007), a lower ATN-ISS (0.41 versus 0.78; P < 0.001), a lower AP1 (16.5 versus 19; P = 0.02) and a lower risk of death as calculated using the AP1 (23% versus 50%; P < 0.001). Non-ICU patients also needed dialysis less often (32% versus 38%; P = 0.003) and had a lower mortality rate (31% versus 78%; P < 0.001), compared to ICU patients. was 39 ± 15 years, and 26 were female. The diagnosis was confirmed in biopsies or necropsies in 44/50 patients. C-ANCA was positive in 26/40 and P-ANCA in 7/40 patients. The initial pulmonary manifestations were characterized by nodules with or without cavitation in 27/50, masses with or without cavitation in 13/50, and alveolar hemorrhage in 9/50. The treatment was prednisone (1 mg/kg) and cyclophosphamide (2-3 mg/kg). The severe cases also received 3 days methylprednisolone 1 g/day. From the 50 patients attended 11 died, 10 lost follow up, and 29 are in remission. The pneumologist should be aware of the pulmonary and systemic presentation of WG in order to diagnose and treat these patients properly.

P43 Effects of PEEP above the L-Pflex on gas exchange, hemodynamic and gastric tonometer in ARDS patients E Silva, CSV Barbas, A Garrido, M Assunção, C Hoelz, EC Meyer, E Knobel Intensive Care Unit of Hospital Israelita Albert Einstein, São Paulo, Brazil
Introduction and method: In order to study the acute effects of optimal PEEP on oxygenation, CO 2 exchange, hemodynamic parameters and gastric mucosal PCO 2 we analyzed 10 ARDS patients (<5 days of installation) after 30 min on PEEP 5 cmH 2 O (T0), then 30 min on PEEP 2 cmH 2 O above the L-Pflex (T1) and than 30 min after PEEP of 5 cmH2O (T2). They were all sedated-paralyzed. A Swan-Ganz catheter with a semicontinuous cardiac output and continuous gastric tonometer was inserted in each patient. The tidal volume and respiratory rate were kept constant (8 ml/kg and 20/min; VCV). L-Pflex was titrated by PxV curve (random volumes). The mean APACHE II was 21.3. Positive end-expiratory pressure was 5 cmH 2 O. Oxygen was administered to provide an arterial oxygen saturation above 90%. The RR, arterial blood gases, arterial pressure, and heart rate were measured on admission, after 2 h, 6 h during NPPV, and 1 h after the patient was weaned.

Results: See
Results: See Table. Discussion: NPPV is a commonly used therapy for the treatment of acute hypercapnic respiratory failure due to COPD exacerbation. The results reported here confirm the effectiveness of NPPV in improving COPD patients in acute respiratory failure. This is demonstrated by the significant fall in RR, the increase in oxygena-tion (not shown), and the fall in PaCO 2 despite neither PSV or BiPAP ™ reduced PaCO 2 significantly. Comparing PSV and BiPAP ™ both are effective. Objective: To identify and weight risk factors to VAP.
Design: Prospective international multicenter study.
Methods: Every patient intubated for more than 12 h was included and followed for 60 days or death to identify the development of VAP. VAP was defined as presence of new infiltrate in the chest radiograph together with at least two of the following criteria: fever; leukocytosis or 10% immature forms or leukopenia; and purulent bronchial secretion. All patients admitted from another hospital were excluded.

Conclusion:
The preliminary results show an associated mortality to VAP that is not related to previous clinical conditions. Reintubation and the use of H 2 -blockers seem to be isolated risk factors. Aim: To evaluate the effects of VAP on morbidity and mortality in critically ill patients.

Methods:
In this retrospective study, 141 ICU patients were evaluated from January 1997 to November 1999. All patients were submitted to artificial ventilation for more than 48 h and did not present signs, symptoms or laboratory tests that could suggest pneumonia at the start of mechanical ventilation. Patients were divided in two groups: group 1 (with VAP) and group 2 (without VAP). The following variables were correlated with VAP: age, APACHE II and time under mechanical ventilation. Statistical analysis included Student's t-test, Mann-Whitney and χ 2 test (P < 0.05).

Results:
No difference was found for age (P = 0.08), mortality (P = 0.25) and for APACHE II values (P = 0.09) between patients from groups 1 and 2. Patients with VAP showed longer ventilation times (P = 0.0001) than patients without VAP (Table).
Conclusion: All preventive methods should be employed to avoid VAP in critically ill patients since the evaluated group in this study remained under mechanical ventilation for a significantly longer period than patients without VAP, although the mortality rate was unaffected.  Cardiopulmonary bypass (CPB) alters pulmonary function and its duration is related to postoperative problems. The lung is the first organ to initiate a clinical response to this inflammatory reaction, translated as an acute lung injury, with ventilation, oxygenation and pulmonary mechanics alterations. The aim of this study was to investigate the immediate changes in lung function after a prolonged (more than 2 h) CPB in cardiac surgeries.

P52 Effects of inhaled nitric oxide combined to mechanic ventilation on the patients with acute respiratory dysfunction in postoperative heart surgery: comparative study among pressure controlled ventilation and volume controlled ventilation FRBG Galas, JOC Auler Jr Instituto do Coração da Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
Introduction: Pressure-controlled ventilation (PCV), is related to a better distribution of the inhaling flow and lower pressure peaks, when compared to volume-controlled ventilation (VCV). Nitric oxide (NO) promotes redistribution of blood flow to the ventilated areas and decreases the pulmonary shunt effect improving oxygenation.

Objectives:
To evaluate the effects of 10 ppm of inhaled nitric oxide, combined to two ventilation modalities -pressure-controlled ventilation and volume-controlled ventilation -on the respiratory function of 40 patients undergoing heart surgery with extracorporeal circulation and respiratory dysfunction characterized by PaO 2 /FiO 2 ratio <200 in postoperative heart surgeries.

Method:
The patients were randomized into four groups: PCVNO group, pressure controlled ventilation with NO; PCVWNO group, pressure-controlled ventilation without NO; VCVWNO group, volume-controlled ventilation without NO; and VCVNO group, volume-controlled ventilation with NO. Evaluations were performed at times zero (baseline), 60, 120, 240 and 360 min. NO was administered in all times for groups I and IV.
Results: There were no significant changes in hemodynamic parameters, peak inspired pressure and oxygenation among the groups. There was a significant difference in the four groups for the following parameters throughout the different times: systolic pulmonary pressure (SPP); diastolic pulmonary pressure (DPP); mean pulmonary pressure (MPP); systolic systemic pressure (SSP); mean blood pressure (PBP); transpulmonary gradient (TPG); pulmonary/systemic vascular resistance index (PVRI/SVRI); ratio of partial arterial oxygen pressure and fractional inspired oxygen concentration (PaO 2 /FiO 2 ); partial arterial carbon dioxide pressure (PaCO 2 ); oxygen consumption index (VO 2 I); pulmonary shunt (Qs/Qt); oxygen extraction rate (O 2 ER); alveolar-arterial oxygen gradient (A-aO 2 )G; and pulmonary compliance (Cst) expressed by hemodynamic and oxygenation improvement.
Conclusions: No significant differences were observed for hemodynamic and respiratory parameters and those related to respiratory mechanics, when volume-controlled ventilation (VCV) was compared to pressure-controlled ventilation (PCV). NO inhalation did not show significant improvement in blood oxygenation of the studied patients. Ventilation time seems to have had a favorable influence on the clinical course. Ideal PEEP was calculated for all patients prior to the study

ICU of Hospital São Domingos, São Luis, Brazil
Objectives: To compare two methods of weaning from mechanical ventilation -once-daily trial of spontaneous ventilation (ODT) and pressure support ventilation (PSV) -analyzing (1) total duration of mechanical ventilation, (2) duration of weaning and (3) frequency of successful weaning.
Patients: All patients submitted to mechanical ventilation for at least 48 h that fulfilled criteria for weaning.

Measurements and main results:
We studied 125 patients submitted to mechanical ventilation for at least 48 h and that had clinical and radiological evidence of improvement of the process that motivated artificial support of respiration in addiction to the following functional and gasometric criteria: PaO 2 /FIO 2 >200 with PEEP of 5 cmH 2 O or less; PI Max smaller than -30 cmH 2 O; and f/VT <100. Patients could not be under deep sedation or curarization, and when using vasoactive drugs (dopamine or dobutamine) the dose could not exceed 5 µg/kg/min. Sixty-five patients were randomized to ODT and 60 to PVS using a simple randomization technique and sealed envelopes. Weaning was considered successful when the patient was liberated from mechanical ventilation, remaining well for at least 48 h. The two groups were comparable in relation to age, gender, APACHE III score and cause of respiratory failure. The total duration of mechanical ventilation was 6.1 ± 6.8 days in the ODT group and 8.7 ± 7.5 days in the PSV group (P < 0.05). Weaning duration was 10.6 ± 25.4 h in the ODT group and 38.7 ± 33.0 h in the PSV group (P < 0.001). Fifty-seven patients (87.0%) were successfully weaned in the ODT group versus 45 (75.0%) in the PSV group (P = 0.6). Twelve (26.1%) patients died in the ODT group against 12 (20.0%) in the PSV group (P = NS).

Conclusions:
This study, similarly to other recent publications, suggests that most patients submitted to mechanical ventilation can be rapidly removed from the ventilator if they present clinical, gasometric and functional conditions and tolerate well a 2-h trial of spontaneous breathing. This approach results in reduction in the duration of artificial airway, mechanical ventilation and weaning with expected reduction in the frequency of complications and cost of hospitalization. Conclusion: Noninvasive positive pressure ventilation prevented reintubation after mechanical ventilation in ARF patients.

SS Mori, M Grunaer, AMG Silva, MA Martins, CRR Carvalho, MBP Amato, CSV Barbas Respiratory ICU, Department of Pathology, Pulmonary Division, University of São Paulo, São Paulo, Brazil
Introduction: PxV curve is a good way to study the mechanical behavior of the respiratory system in animal models; however, it is important to distinguish between the behavior of the PxV curve inside the thorax (PxV curve of the respiratory system) and outside the thorax (PxV curve of the lung) as we studied in isolated lungs models.

Methods:
In order to evaluate the behavior of the curve inside and outside the thorax, we studied 42 Wistar normal rats. In 21 rats we performed the PxV curve of the respiratory system with a constant flow of 1.66 ml after the rats were anesthetized and paralyzed. In the other 21 rats, after we had anesthetized the rats, we excised the lungs from the thorax and performed the PxV curve of the isolated lung with a syringe (Figure). We recorded the curve in a PC computer and then calculated the L-Pflex and the U-Pflex.

Results:
In the 21 rats with closed thoracic cage the mean U-Pflex of the PxV curves was 13.5 ± 1.90. None of the 21 normal rats had L-Pflex. In contrast the isolated lungs showed a mean L-Pflex of 12.05 ± 3.03 and a mean U-Pflex 16.96 ± 2.93 (Figure).

Conclusion:
The PxV curve has a completely different shape inside and outside the thorax, and this fact has to be taken into account during mechanical measurements in rats experimental models. FAPESP-LIM-FMUSP.

P56 MODS in mechanically ventilated patients JAB Froemming, MO Guerreiro, D Oliveira, N Almeida, FS Dias Hospital São Lucas da PUCRS, Porto Alegre, Brazil
Introduction: The need of mechanical ventilation (MV) lead to augment of nosocomial infections and sepsis, length of stay in ICU, as well as MODS. Our purpose was to stratify and correlate the occurrence of MODS with mortality in patients on MV using a specific score.
Methods: This is a retrospective analysis of all patients in the ICU who were on MV between January 1999 and December 2000. Data collected was age, gender, APACHE II score and length of stay (LOS) in ICU. Criteria for MODS were those proposed by Marshall et al. Patients were divided in survivors (SV) and nonsurvivors (NSV) accordingly to ICU survival. The differences between groups were analyzed with t-test, χ 2 and Mann-Whitney as indicated.
Results: During the study period there were 903 admissions, of whom 621 (68%) recquired MV. Mean age was 51.5 ± 18.9 (SV) and 61 ± 17.1 years (NSV; P < 0.0001), 328 (52.8%) were male (NS), and APACHE II was 12.6 ± 6 versus 19.3 ± 7.8 (P < 0.0001) in SV and NSV, respectively. The LOS in ICU was 15 ± 14.6 and 9.6 ± 11.6 days in SV and NSV (P < 0.0001). The results of the MODS in SV and NSV are shown in the Table. Six patients were excluded from this analysis due to lack of data.
Conclusions: Nonsurvivors of mechanical ventilation had higher scores of MODS than SV and also higher individual organ system scores, although severe individual organ dysfunction was not present. Age and APACHE II score at admission also were associated with mortality.

P57 Lung computed tomography during a lung recruitment maneuver on patients with acute respiratory failure: mechanisms and clinical usefulness G Bugedo, A Bruhn, G Hernández, F Cruz, C Varela, JC Tapia, L Castillo Programa de Medicina Intensiva, Departamentos de Anestesiología y Radiología, Pontificia Universidad Católica de Chile, Santiago, Chile
Introduction: Lung computed tomography (CT) has been widely used to assess lung morphology, which has led us to a better understanding on the pathophysiology of ARDS, mechanical ventilation and ventilatory induced lung injury. Despite the absence of controlled studies and standardization, LRM are increasingly used in patients with acute respiratory failure. The objective of our study was to assess the effect of different levels of airway pressure on lung morphology by performing a LRM during the lung CT-scan. This way, we could set the best ventilatory strategy for the patient and identify the mechanisms involved during the LRM.
Methods: Ten patients (5 male, 5 female, 58 ± 16 years old) with ARF (PaO 2 /FiO 2 46-214) underwent a thoracic CT scan for diagnostic or therapeutic reasons. Patients were connected to a Siemens 900-C ventilator in the CT-scan facility, under sedatives and muscle relaxants. We used a Picker PQ2000 CT-scan, which has a workstation for the processing of images. At first, a conventional CT scan from the neck down to the lung basis was performed with CT slices 8 mm thick during an inspiratory pause. Then, PEEP was down to ZEEP and a LRM applied with 5 cmH 2 O increments in PEEP up to 30-40 cmH 2 O. A CT slice from the basal third of the lung during an expiratory pause was performed at each PEEP level. This took 4-6 min and then the patient was back to baseline ventilatory parameters. Arterial blood gases were taken at baseline, ZEEP, 30-40 cmH 2 O PEEP and 3 min after LRM, and airway pressures and tidal volumes registered. Lung slice volumes and densities were measured as previously described [1,2].

Results:
Decreasing PEEP down to 0 cmH 2 O (ZEEP) was associated with an increase in basal densities. The increase in PEEP level from 0 up to 40 cmH 2 O was associated with a significant increase in lung volume in both lungs, because of an increase in gas volume and not change in the amount of lung tissue, even with high levels of PEEP. This was associated with increases in PaO 2 , PaO 2 :FiO 2 ratio and mean airway pressure, and a decrease in tidal volume and total static compliance. Three to five minutes after LRM, there was a significant improvement in oxygenation index, despite similar airway pressures.

Discussion:
This study showed that lung CT scan during a LRM in patients with ARF is safe and gives morphologic and functional information that could be useful in setting ventilatory parameters. By the other way, LRM improves lung mechanics and oxygenation in the short-term period, probably by effectively opening previously closed alveoli. The time course of these effects is still unknown.

P58 Impact of weaning failure in the evolution of patients under mechanical ventilation G Bugedo, A Bruhn, F Apablaza, F Bernucci, V Segovia, P Zúñiga, G Hernández, L Castillo Programa de Medicina Intensiva y Departamento de Anestesiología, Facultad de Medicina, Pontificia Universidad Católica de Chile, Chile
Introduction: Weaning is a critical period in the evolution acute respiratory failure (ARF) patients. Weaning failure has been associated with increased morbidity and mortality. We evaluated the impact of weaning failure on mortality, and morbidity.

Methods:
Patients who were admitted to our eight-bed surgical-ICU and stayed more than 24 h on MV were prospectively evaluated from June 1999 to June 2000. Demographics, ARF etiology, APACHE II, and gas exchange and mechanical parameters were assessed. A protocol-directed weaning consisting in a 2-h trial of low levels of pressure support ventilation and PEEP was used before extubation. Weaning failure was defined as reintubation within 48 h after extubation. Weaning failure (WF) patients were compared with those who were successfully extubated (SE), and also with the total group (TG = SE + WF + patients who died before attempting weaning). Outcome measures were mortality, MV and ICU length of stay, and MV-free days (30-days on MV).

ICU of Hospital Israelita Albert Einstein, São Paulo, Brazil
Introduction: The evaluation of respiratory mechanics through an esophageal balloon can improve the evolution of a difficult weaning.

Method:
We originally studied eight patients, and change in medical weaning procedures were evaluated, before and after the respiratory mechanics measurements. Later, the study was modified and another 10 patients were observed according to the modification on clinical diagnosis of the respiratory failure (if the problem was related to compliance, resistance, drive or muscle dysfunction). The agreement among three observers that were asked to make the diagnosis were evaluated, before and after the measurements.

Results:
The compliance was reduced in 10 patients (mean 47.72 ± 26.89 ml/cmH 2 O); respiratory drive was assessed through the measurement of P0.1 and was increased in two patients and reduced in seven (mean 2.7 ± 3.3 cmH 2 O); esophageal pressure was increased in five patients and reduced in two (mean 13.57 ± 10.08 cmH 2 O); respiratory work was increased in four patients and reduced in one (mean 1.04 ± 0.56 J/l), both, esophageal pressure and respiratory work was observed only in 10 of the 18 patients; airway resistance was increased in 16 patients (mean 15.34 ± 9.16 cmH 2 O/l/s). The mean of respiratory rate (RR)/tidal volume (Vt) index was 123.4 ± 85.4 and was over 105 in eight out of 17 patients. There was difference in clinical diagnosis in 50% of the time, before and after measurements. The changes in clinical diagnosis happened in eight out of 10 patients (P = 0.057) and in weaning procedures in 14 out of 18 patients (P = 0.018). Evolution of weaning was satisfactory in 11 out of 16 patients (P = 0.059).

Conclusion:
These results show how important could be the measurements of respiratory mechanics, when the weaning is difficult, modifying the clinical diagnosis as well as the weaning procedures, contributing to a better outcome.

P60 Association between ventilation parameters and outcomes in acute respiratory failure patients ES Oliveira, ES Boschi, H Guths, C Teixeira, S Brodt, E Monteiro, CA Polanczyk, NB Silva Centro de Terapia Intensivo do Hospital Moinhos de Vento, Porto Alegre, Brazil
Background: In recent years, several studies have described different strategies for ventilatory support, some of them associated with lower morbidity and mortality. Although lower tidal volume ventilation seems to be preferred over traditional volumes, there is a great variability in clinical practice. Scarce data exist describing daily practice in patients managed in intensive care units outside clinical trials and in nonacademic institutions.
Objectives: (1) To describe mechanical ventilation parameters in patients admitted to our intensive care unit, and (2) to evaluate the effect of lower volume ventilation compared with traditional ventilation on clinical outcomes.

Method: Consecutive patients admitted between June and
November 2000 in the medical-surgical ICU, who required mechanical ventilation for more than 24 h because of acute respiratory failure, were included in this observational study. Clinical and ventilatory parameters were recorded at baseline, soon after initiation of mechanical support, and within 36-48 h. Patients were stratified into two groups: group I, patients ventilated with lower tidal volumes (<8 ml/kg); and group II, patients ventilated with higher volumes (≥8 ml/kg). Multivariate analyses for repeated measures were performed to evaluate the independent effect of lower minute volume ventilation on mortality and duration of mechanical ventilation.
Results: A total of 58 patients were enrolled in the study (mean age 66 ± 18 [20-98] years, 39 [66%] were male and mean APACHE II score of 20 ± 7). Primary modes of mechanical ventilation were pressure-control ventilation (73%), pressure-support ventilation (25%) and synchronized intermittent mandatory ventilation (2%). Sixty-one per cent of the patients were initially ventilated with volumes greater than 8 ml/kg (Table). Tidal volumes did not differ from baseline to 36 h (8.9 ± 2 versus 8.9 ± 3 ml/kg; P = 0.89). Both groups were similar in their demographics and causes of respiratory failure.
In multivariate analysis, after adjustment for the clinical differences between groups, tidal volumes were not independently associated with mortality and ventilator time. Patients managed with higher tidal volumes (≥10 ml/kg) at 36 h had prolonged mechanical ventilation (9 ± 8 versus 6 ± 4 days; P = 0.05). Other ventilator settings such as FiO 2 , pressure control mode and maximal inspiratory pressure at 36 h were significantly associated with increased mortality.

Conclusion:
In this heterogeneous cohort of mechanically ventilated patients, pressure control and pressure support were the preferred modes of mechanical ventilation, and traditional tidal volumes (greater than 8 ml/kg) were utilized in the majority of the cases. Although our results showed a nonsignificant difference in mortality, there was a trend towards shorter ventilator times in patients ventilated with lower tidal volumes.  Results: The figure bellow shows an endemic curve of MRB, considering a two-year-period of routine surveillance. As shown, there is a clear relationship between work overload and peaks of isolation of MRB above the upper limit in the endemic curve.

Conclusion:
Excessive workload in this ICU is related to an increasing rate of recovery of MRB, probably due to inadequate compliance to handwashing.

Conclusion:
Hand-washing compliance in our ICU is low and comparable to rates described in the medical literature. Contact precautions for patients colonized/infected with multidrug-resistant bacteria significantly enhances hand-washing compliance practices, mainly after patient care. A careful evaluation should be focused on other beneficial effects of strict contact isolation policies, such as decreasing rates of nosocomial infections or lower rates of recovery of multidrug-resistant organisms. Objectives: To evaluate compliance rates to institutional nosocomial infection preventive measures and the effect of a quality improvement strategy on compliance rates.

Methods:
During two distinct periods (October 1998 and June 1999), compliance to specific nosocomial preventive measures related to respiratory, bloodstream and urinary infections (defined according to institutional guidelines) were recorded by direct patient observation and chart reviews. Compliance rates were discussed with the multidisciplinary team, and low-compliance practices were focused and re-emphasized after the first surveillance. Subsequent surveillance evaluated improvement of compliance rates.
Results: General compliance to selected nosocomial infection preventive measures improved from 75.5% during October 1998 to 87% during June 1999 (P < 0.05). Higher compliance rates were observed to preventive measures related to urinary infections (88-94%), catheter-related infections (75-89%) as well as to respiratory infections (67-76%). General compliance rates remained high in a further surveillance (85.7% in February 2000). Concomitantly with higher compliance practices, the ICU general nosocomial infection rate decreased from 27.7 infections/1000 patients/day in 1998 to 20.6 infections/1000 patients/day in 1999.
Conclusion: General compliance rates to nosocomial infection preventive measures is high in our ICU, with lower rates related to prevention of respiratory infections. Quality improvement tools, such as discussing low compliance rates and retraining the multidisciplinary team, are useful to increase compliance rates. Higher compliance to preventive methods was associated with a decrease in the general nosocomial infection rate, although a causal relationship needs to be investigated. Objective: Description of the microbiological patterns and markers of NP in patients submitted to heart surgery.

Development and method:
An observational and prospective study was conducted between June 2000 and February 2001. All patients submitted to heart surgery and to MV were included. Diagnosis of NP followed NNISS criteria (CDC). We evaluated the results of bronchoalveolar lavage (BAL) and blood cultures collected at the same day of NP diagnosis. Variables analyzed were age, gender, smoking, diabetes, chronic obstructive pulmonary (COPD) disease, body surface, ventricular function, time of extra-corporeal circulation (ECC), clamp time, type and length of stay (LOS) in surgery, LOS MV. EPI Info 6.04 from CDC was used to perform univaried analysis.
Results: A total of 211 patients were submitted to heart surgery during this period; 29 NP were observed in 23 (11%) patients. Median age of 66 years, 65% were men. Gender, COPD, diabetes and body surface were not related to increase NP. Smoking patients had increased risk of NP (P < 0.001). Patients with normal ventricular function had a lesser incidence of NP (P = 0.002). LOS in surgery (median 6 h) and clamp time was not related to NP. LOS MV (P < 0.001), duration of ECC (P < 0.001), coronary artery bypass graft (P = 0.04) and emergency (P = 0.01) were related to increase of NP. BAL could not be performed in two cases of NP. Micro-organisms related to these infections were Pseudomonas

P65 Epidemiology, diagnosis and prognosis of critically ill patients with positive fungal cultures KMV Santos, JR Azevedo UTI, Hospital São Domingos, São Luis, Maranhão, Brazil
Introduction: Fungal infection in critically ill patients is an increasingly prevalent problem [1]. Candida spp cause the majority of these infections in ICU. The significance of a positive culture has been debated as it may represent local colonization or disseminated infection [2].
Objectives: This study analyzed the clinical significance of positive fungus cultures in the ICU patient.

Method:
We reviewed the charts of all patients with at least one positive fungal culture who were admitted to a 13-bed general intensive care unit between 01/02/98 and 31/01/2000. We analyzed the following: age, APACHE III score, length of stay in the ICU, diagnosis, site and species of fungal isolation, risk factors and treatment. The patients were classified according to the clinical profile, microbiological data and therapeutic interventions in five groups: probable fungal infection, empiric therapy, fungemia, confirmed fungal infection and colonization. Objective: To describe an outbreak of SCV and its epidemiology.

Materials and method:
We conducted a retrospective study analyzing nine previously identified cases (two of them out of the ICU) of SCV-related sepsis occurring in the period between November 1998 and September 1999. Clinical and epidemiologic data were collected and compared to patients with MRSA (non-SCV) infection. Conclusion: This is a unique study on this subject in Brazil, and its original data confirm previous description of infections caused by S aureus SCV whose characteristics result from its phenotypical adaptations. A worse prognosis is usually associated with this strain, which are a cause of more persistent, recurrent and resistant infections; in this case an ominous prognosis is worsened by methicillin resistance. . This protocol specified that for all cases a written justification is provided by the responsible physician, although no direct intervention is expected on the medical order. Appropriateness was established by the investigators through prospective collection of clinical data and chart review. Antibiotic prescription was evaluated regarding its indication, empirical use, pharmacokinetics and duration of treatment. Clinical outcomes evaluated were infection worsening or cure and mortality.

Results
Results: A total of 137 antibiotic prescriptions were studied, from 90 patients. Sixty-six per cent were male, age ranged from 17 to 98 years, 61% were older than 61 years, and 61 (68%) medical and 29 (32%) were surgical cases. Among these patients, 81 infections were observed, predominantly respiratory infections (48 [59%] episodes) and sepsis (28 [34%] episodes), and less frequently other infections (abdominal, endocardites, gaseous gangrene, urinary tract, phlebitis). Nosocomial infection occurred in 61 (75.3%) episodes, and in 13 (16.7%) cases immunodeficiency was associated. One or more etiologic agent was only identified in 44 (54%) episodes, 54% Gram-negative bacilli and 43% Gram-positive cocci. Antibiotic use was empirical in 54.4%, etiology guided in 27.8% and in 2.2% no infection was observed. According to criteria defined by ICS, appropriate antibiotic use was observed in only 39% of prescriptions, and the majority were considered inappropriate (61%). Prescriptions were considered inappropriate because of inadequate choice of the drug (44 episodes); errors in doses, intervals or duration (five episodes); choice of combined drugs (one episode); and no adjustment after antibiogram release (two episodes). There was no statistical difference in the appropriateness between empirical (57%) and nonempirical (44%) antibiotic use. Treatment of community-acquired infections were more inappropriate than nosocomial infections (73% versus 54%; P < 0.05). However, empirical or appropriate use was not associated with clinical outcomes. Empirical treatment had similar rates of cure (54.5% versus 45.5%) or worsening (58.3% versus 41.6%) to nonempirical treatment, respectively. Although not statistically significant, appropriate use had a cure rate lower than inappropriate use (40% versus 60%), probably due to other clinical factors besides antibiotic use.

Conclusion:
Antibiotic use in an ICU setting is empirical in majority of the cases, probably due to the lack of an etiologic agent identified in half of the episodes, and high complexity of patients. In the present study, empirical or inappropriate use did not seem to influence clinical outcome. Appropriateness of antibiotic use for ICU patients may need to consider other criteria than those used for regular patients.

P69 The evaluation of intracranial pressure by the carotid eco-color Doppler JC Tress, AL Martinez Filho, M Lugarinho, MF Knibel
Hospital de Clínicas Mario Lioni -Caxias, Rio de Janeiro, Brazil Introduction: The evaluation of intracranial pressure (ICP) is useful in several clinical situations. The value of the ICP in centimeters of water is available by a specific and invasive catheter in many hospitals. A simple and noninvasive method for assessing ICP would be of considerable value. This is particularly true with respect to cerebral brain because of the recent interest in the effects of cerebral flow and efforts to understand neurologic dysfunction.
Objective: Our intention in this study is to demonstrate, for the first time, the possibility of the ICP value to be described by the carotid color Doppler method. To our knowledge, no comparison between carotid color Doppler method and ICP available for invasive catheter has been performed until now.

Method:
After institutional approval by the local ethical committee on human research, we studied 15 individuals in an intensive care unit by the carotid color Doppler method before transferring them to the surgery center for invasive catheter intracranial introduction.
Results: Their mean age was 40 years, their mean body height was 170 ± 5 cm and mean weight was 68.4 ± 10.2 kg. A 7.5-MHz linear pulsed carotid color Doppler device was used to evaluate the flow, the carotid wave, the pulsatility index and the resistance index. The ICP index of the group was subdivided in normal value between 5-15 cmH 2 O; moderate >20 cmH 2 O; severe >40 cmH 2 O; and critical >60 cmH 2 O, as first described by Stene J in 1997.
When the normal value was observed in ICP, the typical normal flow in carotid method was also observed. Moderate elevation in ICP value was represented by higher systolic flow in carotid Doppler than the normal value, while extremes values were observed with higher systolic flow and inversion of diastolic flow in comparison with the baseline. In the critical ICP value, the systolic flow in the carotid method was attenuated and the diastolic flow disappeared.

Conclusion:
The carotid color Doppler method is indicated to analyze the elevation of ICP.
P70 Immediate postoperative analgesia and sedation following heart surgery: a comparative analysis of dexmedetomidine chlorohydrate versus remifentanyl hydrochloride Results: Statistical analysis of data was performed within 10 h after patient admission to the post-operative ICU. Like the Ramsay Scale, VAS, independently of time, showed a significant difference between the two groups (P < 0.001), with group I displaying the lowest values. Over time, group II continued to display lower values, but this difference was not significant (P > 0.1).

Conclusion:
Both drugs proved effective for controlling pain and anxiety. RH was more efficient in this control, especially when time was not considered, based on the better results in the first 4 h of the postoperative period. A larger patient sample is needed for more adequate evaluation of the results. other calls were about suspected but not confirmed cases (16.7%), prophylaxis and diagnosis (21.7%), preoperative evaluation in susceptible patients (10%) and general scientific information about the disease (6.7%). The main objective of the 'hotline' was to direct the assistance in confirmed cases of malignant hyperthermia. We had seven (11.6%) calls that were related to malignant hyperthermia cases.
Conclusions: Malignant hyperthermia is still a disease with high morbidity and mortality, which is poorly diagnosed and inappropriately treated. The maintenance of a 'hotline' system 24 h/day is justified not only because of the emergency characteristic of the disease, but also for complementary evaluation and information related to the diagnosis, treatment and prevention in susceptible patients. Introduction: Monitoring of severely head-injured and postoperative neurosurgical patients is essential to optimize cerebral hemodynamics and thus to minimize secondary injuries. We investigated the correlation between cerebral variables obtained in the first 72 h and survival.

Methods:
This was a prospective study in 14 patients in a 24-bed adult ICU. After initial resuscitation, cerebral monitoring was performed and cerebral perfusion pressure (CPP) was increased to 70 mmHg by an increase in mean arterial pressure (MAP) with volume expansion and vasopressors as needed.

Conclusion:
In the first 72 h, ICP was significantly higher and CPP significantly lower in nonsurvivors. Dynamic evaluation in the first 72 h of injury shows trends towards higher SjvO 2 in nonsur-vivors (NS). When patients were initially resuscitated before cerebral monitoring we found no correlation between SjvO 2 and CPP.

P74 Study of 531 consecutive cases of severe head trauma in Florianópolis, 1994-2000 ET Martins, TS Silva
Intensive Care Unit and Neurotrauma Clinic, Hospital Celso Ramos, Florianópolis, Brazil Background and objective: Trauma is the major cause of mortality in the population aged below 40 years. Brazil has a high incidence of traffic accidents. Our main objective was to study the epidemiology and the mortality secondary to severe head trauma in a mediumsized southern Brazilian city (Florianopolis, ca 600,000 inhabitants). We compared the impact of safety traffic campaigns on epidemiological variations and mortality during the period 1994-2000.
Settings: A regional reference hospital for head trauma.
Method: Data from 531 consecutive patients admitted to the ICU (period 1994-2000) with severe head trauma (Glasgow Coma Score ≤ 8) were obtained. The following variables were collected and analyzed: demographics, cause of trauma, Marshall's topographic classification for head trauma and in-hospital mortality. We compared total mortality and mortality during the periods 1994-1995 and 1999-2000.

Results:
Patients were predominantly males (85%), aged 12 to 40 years (74%). In-hospital mortality was 35%; in 1994-1995 it was 44%, and in 1999-2000 it was 32%. There was a fall in the percentage of victims of car accidents from 33 to 21%, and an increase in the percentage of victims of motorcycle accidents from 13.4 to 21% and of pedestrian injuries from 31 to 33.4%. We observed an increase in injury type V (mass lesion evacuated) from 29 to 35%. Description: Currently, there are three most critical issues concerning the performance of nursing technical procedures: the high number of procedures; the short time available to train the staff on the job; and the difficulty of measuring the effectiveness of the training program. We observed and received some complaints from patients' families that some special procedures were not performed in a uniform way. One of these was continuous ambulatory peritoneal dialysis (CAPD).
Quality indicators were elected for peritoneal dialysis. The initial analysis showed that the worst results were related to the incidence of peritonitis or peritoneal dialysis technique-related infection. In the period from October to December 1998, there were three episodes of infection in 68 patient-days (one peritonitis to each 1.3 patient-month). A workshop training program was devel-oped to improve the nursing performance in CAPD procedure. Next, we applied a PDCA deming cycle (January 1999): 'plan', evaluation of the technique used and also the training program development; 'do', training of the nursing staff; 'check', re-evaluation of the technique and new analysis of infection incidence; and 'act', retraining (if necessary) and continuous nurse education.
Evaluation: Fifty-six nurses (100%) were trained. When we evaluated the understanding of the technique, twenty-five of them (44%) were not fully compliant with the standard technique and had to be retrained. Afterward a new evaluation revealed that all of them were then compliant (Fisher's exact test, P < 0.001). During January to June 1999, we observed no new cases of peritonitis in 94 patient-days (incidence-density analysis, P = 0.07).
Outcomes: This preventive approach allows a practical and systematic feedback from the professional involved, a uniform procedure performance, a customized retraining, and detection of technical faults before the real performance with patients. Objective: The aim of this work was to make a descriptive study about the ICU patients and care givers satisfaction at a general hospital.
Available online http://ccforum.com/supplements/5/S3 Critical Care Vol 5 Suppl 3 First International Symposium on Intensive Care and Emergency Medicine for Latin America Material and methods: This is a prevalence study conducted during a period of 3 months. The sample is composed by 724 interviews (356 care givers and 368 patients), according to the inclusion criteria previously established. The instrument was a questionnaire to assess the patients' and families' satisfaction, developed especially for this purpose and is composed by Linkert scale (1-7).

Results:
The mean age of the interviewed was 56.7 years (SD = 17.5 years), predominantly of female sex (60.5%). In the sample, 61.7% had university degree. Sixty-six per cent of the individuals were married. Seventy-seven per cent of the care givers were relatives (son or husband or wife) and 63% of the patients had had previous admissions at the hospital. The total satisfaction score was 6.14, and 98% of the interviewed recommended the service. The score of the variable 'expectation with received service' was 6.2, with no difference for sex, age and length of stay.

Conclusion:
We have previously identified a tendency of high level of satisfaction. This tendency was associated with scores for expectation and recommendation. The user's satisfaction is the most important indicator for measure the quality of care. However, this indicator is not precise and it must be continuously improved to provide the best information about satisfaction. Objective: The aim of this study was to compare the perceived needs of family members of patients in the intensive care unit with those perceived by health care team using the 'Critical Care Family Needs Inventory' (CCFNI).

Materials and method:
The sample is composed by 72 family members of patients hospitalized in ICUs, as well as 86 members of the health care team, from 1 August to 31 December 1997. The CCFNI scale was translated into Portuguese and three questions were added. The data obtained were analyzed using the mean and the standard deviation of the answers, and the Pearson's correlation was used to compare the samples.

Results:
Information and assurance were perceived as being the major needs by the relatives and the multiprofissional team. A significant correlation was found between the score obtained for both groups (r = 0.89; P < 0.001). The mean scores evaluated by the relatives were higher than those perceived by the health care team.

Conclusion:
The main categories of needs were assurance and information about the real conditions of their hospitalized relatives; there is a strong correlation between the family evaluation and the perception of the health care team. Despite advances in its management, pain is a frequent problem in ICU. It is a major determinant of patient stress and it is also correlated with morbidity, probably due to sympathetic activation, respiratory restriction, immobility, etc. Several studies have tried to validate different tools for analgesia evaluation, but they fail to evaluate the impact of pain management strategies on patient satisfaction.
Our objective was to evaluate whether different pain management strategies alter postoperative ICU patient satisfaction reports. A total of 110 postoperative patients without evident cognitive deficits were evaluated. We obtained data about type of surgery, type of analgesia used (continuous or intermittent, regularly administered or on a patient-demand basis), patient pain scores from an analogic-visual pain scale (AVPS: 0, no pain; 4, moderate pain; 10, most severe pain) and patient satisfaction scores at the moment they left the ICU.
Sixty per cent of the patients were males, 40% were females, and mean age was 63 ± 17 years (mean ± SE). Of the patients investigated 82% gave high satisfaction scores with the analgesia strategy used, but 18% (20 patients) were not satisfied, referring they had unbearable pain during ICU stay; from those 20 patients, 10 (50%) never referred a pain score above 3 during ICU, 13 (66%) were female and 16 (80%) did not receive analgesia on a regular basis.
Our data suggest that evaluation of satisfaction with pain management in ICU should take into account pain scores, but also a specific satisfaction questionnaire. We could observe that female and patients with on-demand-basis analgesia are more prone to refer low levels of satisfaction with pain management. Further, simple pain scores like the classical analogic-visual pain scale may fail to detect pain in the ICU patient because of a putative high incidence of a communication disorder. a major concern; 52% thought about death; 31% did not utilize audiovisual equipment; 36% considered health care providers close enough; and 71% of the comments about the unit were positive.

Conclusion:
We described a simple analysis of humanistic care in general ICUs. Consistent data can be obtained to direct the attention of care providers to critical issues related to the comfort and satisfaction of critically ill patients. Results: A total of 82 questionnaires were answered. The majority of those who answered the questionnaire (94%) had withheld and withdrawn life-sustaining medical treatment. Decisions were more commonly made by physicians, and the younger physicians were more likely to admit patients with no survival expectancy. Dialysis was the therapy most frequently withheld and withdrawn. Sedation or analgesia were less frequently withheld or withdrawn. The most frequently factors taken under consideration for nonadmission into the intensive care were diagnosis and prognosis. To ensure comfort to the patient with no survival expectancy is the most important factor in his admission into an ICU.

Conclusions:
Despite the discomfort in forgoing treatment, the majority of critical care professionals have been discussing forgoing treatment in irreversible, terminally ill patients. It is a serious ethical matter that needs to be studied. Introduction: Compassionate and humane care was recently incorporated into standard intensive care units. Alleviation of stress and discomfort is now recognized as an important step during the treatment of critically ill patients. The impact and relevance of this issue have been largely discussed but not yet fully evaluated. The authors hypothesized that conscious patients might provide important information that can result in improved compassionate care in adult ICUs.

Materials and method:
Between November 1995 and February 1997, 138 patients admitted in the ICU with total alertness and preserved cognitive function for at least 3 days were asked to answer a questionnaire elaborated by the multidisciplinary team. Questions focused on aspects related to well-being and comfort of the patients: ambient temperature, noise, satisfaction with health care providers, sleepiness, pain, time orientation, complaints, and psychological reactions.

Results:
The temperature was considered fair by 60% of the patients, 18% felt hot and 22% cold; 85% of the patients considered general professional care satisfactory; 82% were bothered by loud noise; 46% did not sleep during the night; 45% refer pain; 11% were not time oriented; and 17% had at least one complaint. Anxiety (47%) and fear (35%) were the most common psychological reactions.

Conclusion:
The data suggest that short and simple questionnaires applied periodically to conscious patients might identify factors of stress and discomfort during ICU stay. This is an efficient and relatively inexpensive tool to improve the quality of care provided by a multidisciplinary team.

Pro-Cardiaco Hospital/PROCEP, Rio de Janeiro, Brazil
A short unit is a new concept of emergency medicine where patients are under the care of a proper staff connected daily to the emergency department staff. This remains true even considering that patients are also admitted to the unit from other care sites or at the request of other services.
It is a protocol-driven unit designed for patients who require shortterm interventions or additional time for treatment or diagnosis; it is not intended for patients with significant illnesses that require full hospital level services, including significant interventions. Patients who are not able to complete their course of treatment and leave the unit to home at about 48 h are supposed to be transferred to regular units.
The short stay unit has been designed as a unit for care of patients who need a short time for additional treatment on diagnosis. From September 1999 to March 2001, 945 consecutive patients were admitted to Pró-Cardíaco short stay unit. Approximately 66% of these came from the emergency department, and about 80% could be discharged home from the unit. Mean age of the patients was 65 years, with a mean time of hospital stay of 1.83 days. Fifty per cent of admissions had a cardiovascular origin with a mean time of stay of 1.88 days, and 50% were of noncardiovascular origin (mean time of stay 1.78 days).
Excluding admissions secondary to intrahospital interventions (which were about 25%), the most frequent diagnosis were as follows: chest pain 16%, 1.4 days; infectious syndromes 9.3%, 2.0 days; atrial fibrillation/flutter 8.6%, 1.66 days; syncope 5.5%, 1.38 days; heart failure 4.3%, 2.5 days; and TIA/ischemic stroke 3.9%, 1.7-2.5 days. Results: During the implementation, the most important contributing factors were the multiprofessional structure of the Quality Committee and the need for exactness and preciseness in the patient carerelated services. The main limiting factors were the difficulty on comprehension and adaptation of the model to the patient care services and the characteristic of autonomy of the medical practice. As a result of the process, it was clear for the leaders that the greatest benefits were related to process control mechanisms. These include the fol-lowing: standardization and documentation of policies, technical procedures and administrative routines; mandatory records for critical process; internal and external auditing systems; and equipment maintenance control. Concerning the use of ISO as a tool for marketing promotion, leaders agreed that the certification did not impact positively on the demand of the services. One final result relates to its ineffectiveness in implementing a quality management system, due to its lack on leadership and quality improvement requirements.

Conclusion:
Results indicate that ISO 9002 can be a possible and useful alternative for health care services, mainly if effective mechanisms for standardization and control of their processes are not yet in place. Also, ISO implementation may be useful for services with little experience on quality initiatives that are willing to adopt it as a first step towards a quality management system.

Conclusions:
The Cochrane Institute meta-analysis comparing the use versus no use of human albumin in critically ill patients to restore volemia or to treat hypoalbuminaemia and that concluded that there was an increase in the mortality rate within the patients that used albumin, radically modified albumin consumption. Roberts et al. [3] analyzed the consumption of human albumin in the UK in the period extending from January 1993 to December 1998. In Scotland, the consumption that used to be stable, dropped 65% starting from July 1998. In the remainder of the UK the fall was of 45%.
In our Service, comparing two periods of 5 months, before and after the publication of the meta-analysis, the reduction in the consumption of human albumin was of 80%. Furthermore, it was not observed mortality or morbidity difference concerning this approach change. The costs of hospitalization, however, were considerably reduced with the restriction of albumin use.
If we consider the elevation of the costs of the treatment when albumin is used, compared to other plasmatic expansors, the nonexistence of differences in the morbidity/mortality is already a strong argument in favor of the substitution of albumin for volemic expansion of critically ill patients, and to use an approach based on a precocious and well-designed nutritional support to correct hypoalbuminemia. Introduction: Thrombocytopenia is a common laboratory abnormality in intensive care units (ICU), and generally results from multifactorial causes. The goal of this study was to determine the incidence of thrombocytopenia and the correlation with length of ICU stay, mortality rate, admission severity scores APACHE II and SAPS II, and multiple organ dysfunction scores SOFA and LODS.

Method:
We evaluated patients admitted in a general ICU from January to July 2000 and collected the referring data to APACHE II, SAPS II, SOFA and LODS correlated with platelet count at the admission day and daily during ICU stay. We also obtained the mortality rate and the incidence of bleeding. We considered thrombocytopenia platelet count <150 000.

Results:
The total of 326 patients were analyzed in 7 months. The group of thrombocytopenia patients (n = 94) had longer ICU stay, higher APACHE II, SAPS II, LODS and SOFA as well as higher mortality rate.
Conclusions: Thrombocytopenia constitutes 28.90% of the population admitted at ICU and its development is predictive element for longer ICU stay and mortality rate. It is associate with worse prognosis index and higher organic dysfunction in the first day. Introduction: Multiple organ dysfunction has been recognized as a major factor associated with mortality in patients with acute respiratory failure (ARF). To investigate whether early and late onset ARF can present different patterns of nonpulmonary associated organ dysfunction (OD), a prospective data bank was created with physiological variables and organ function scores.

Methods:
For the purpose of this study, 313 patients who stayed in the ICU for more than 48 h were prospectively evaluated from April to July 1999. ARF was defined as a PaO 2 /FiO 2 ratio less than 200 mmHg and the need for any form of respiratory support. The group of early ARF included the patients who met the criteria for ARF at the time of ICU admission (123/313, 39%) and late ARF those who met 48 h after ICU admission (50/313, 16%). Organ failure was defined as a SOFA score of ≥3 points in each system.

Results:
The most frequently associated nonpulmonary OD was cardiovascular dysfunction (25%) for early-onset ARF, and neurologic dysfunction (36%) for late-onset ARF (Figure). Nonsurvivors and survivors of early ARF had similar respiratory scores on admis-

Conclusion:
The process of evolution of early ARF is related to cardiovascular dysfunction. The recognized pathogenic sequence of nosocomial pneumonia is oropharyngeal colonization and the aspiration of gastric contents could be related to the neurologic dysfunction in late ARF. The degree of initial respiratory dysfunction was not a reliable prognostic indicator. Trends in oxygenation and nonpulmonary compromise at 48 h are more useful. Introduction: Signs and symptoms of shock are not only the direct effect of endotoxin and proinflammatory cytokines. When the process progresses to malperfusion and organ failure, activation of the coagulation system comes into play. Early diagnosis and treatment are thus required to improve the clinical management of DIC.
Conclusion: Low concentrations of AT on admission are the best predictor for DIC. Efforts should be directed to this group of patients to improve outcome. Moderate and severe DIC carry a very high mortality. Objective: C-reactive protein (CRP) increases in response to infection, trauma, ischemia, burns, and inflammatory conditions. Although used frequently in the ICU setting as a marker of systemic inflammation, its relation with organ damage is not well known. This study assessed the association between early serum CRP levels and the development of organ failure (OF) and mortality in ICU patients.
Design: A prospective cohort study conducted in a 31-bed intensive care unit of a university hospital.
Patients: A total of 307 admitted within a 4-month period.

Conclusion:
Elevated concentrations of serum CRP on admission are potential indicators of an increased risk of organ failure and dying.

P93 Predictors of mortality and prolonged mechanical ventilation in patients admitted to a medical-surgical intensive care unit ES Oliveira, ES Boschi, H Guths, F Alves, MM Silva, S Marques, CA Polanczyk, NB Silva Centro de Terapia Intensivo do Hospital Moinhos de Vento, Porto Alegre, Brazil
Background: Ventilatory support has become a major therapeutic modality in intensive care units. However, scarce data exist on the clinical characteristics and prognosis of patients managed in private hospitals in Brazil.

Purpose:
The objectives of this study are (1) to describe demographics, clinical features, physiologic parameters, and prognosis of patients on mechanical ventilation admitted to the Intensive Care Unit of Hospital Moinhos de Vento; and (2) to identify predictors of mortality and ventilator time.
Methods: All consecutive patients admitted between June and November 2000 in the medical-surgical intensive care unit, who required mechanical ventilation for more than 24 h because of acute respiratory failure, were included in this observational study. Clinical and ventilatory parameters were recorded twice daily, within 8-12 h intervals. Major end-points evaluated were mortality and duration of mechanical ventilation. Multivariate analyses were performed to identify independent predictors of prognosis.
Results: Fifty-nine patients (in 794 screening evaluations) were studied, mean age of 66 ± 18 (20-98) years, 39 (66%) were male, and mean APACHE II score of 20 ± 7. Most frequent causes of acute respiratory failure were nosocomial respiratory infection (14%), community-acquired pneumonia (12%) and acute neurologic injury (24%). Similar proportion of patients had primary respiratory (42%) and nonrespiratory (58%) disorders. In-hospital mortality was 31% (18 patients). In univariate analysis, age, APACHE II score, primary respiratory disorders, inotropic use, heart rate and inspired fraction of oxygen (FiO 2 ) at baseline were associated with increased hospital mortality (Table). Chest radiographic findings at admission, such as pulmonary infiltrates and severity score, were not significantly associated with hospital outcome. However, by multivariate analysis, APACHE II was the only independent predictor of mortality.
Duration of mechanical ventilation was 8 ± 8 days (median 7 days) and length of ICU stay was 14 ± 12 days (median 10 days). Predictors of prolonged mechanical ventilation were low ratio of PaO 2 /FiO 2 , high static compliance and inotropic use at baseline. Mortality was higher after 3 days of mechanical ventilation (31% versus 17%), although the difference was not statistically significant.

Conclusion:
In this heterogeneous cohort of medical-surgical patients, demographics and clinical features were similar to those described in other studies. Indications for mechanical ventilation showed a pattern resembling other ICUs in Brazil, but were different from other countries. Hospital prognosis and predictors of mortality and prolonged mechanical ventilation does not appear to be different from other institutions. Nevertheless, these results, in conjunction with prior studies, may help planning resource allocation more effectively in the ICU. Table   Variable Odds Introduction: Burn injury is associated with intense immunoinflammatory activity and release of mediators that perpetuate an inflam-matory cascade causing damage to many organs. It appears that tumor necrosis factor (TNF)-α levels are related to poor prognosis