- Paper Report
- Open Access
Ward interventions prior to ICU admission
- Richard Venn
© Current Science Ltd 1999
- Published: 23 June 1999
- APACHE II
- intensive care
- outcome prediction
- severity of illness index
The authors have previously shown that patients admitted to the intensive care unit (ICU) from the ward have the highest mortality. Other studies have shown that physiological derangements often precede cardiac arrests occurring inside hospital. Consequently it should be possible to identify, at an early stage, those ward patients who have become seriously ill and require critical care, and so improve outcome.
To identify physiological derangements and interventions occurring prior to admission of ward patients to the ICU.
All patients admitted to the ICU from a ward during a 13 month period (1995/1996) were followed up prospectively. Patients admitted to the hospital for less than 24 h or who had undergone surgery within the 24 h prior to ICU admission were excluded. Physiological variables were assigned APACHE II points and scores were recorded for three time periods prior to ICU admission: 0-6 h, 6-12 h, and 12-24 h. Procedures or interventions prior to ICU admission were recorded, and included administration of continuous positive airway pressure (CPAP), oxygen saturation monitoring and the need for cardiopulmonary rescuscitation (CPR).
Of the 923 admissions to the ICU over the 13 month period, 79 admissions fulfilled all criteria in 76 patients (some patients were admitted twice). Although the majority of admissions occurred in daylight hours they were spread evenly over the week days and weekends. Forty-seven percent of patients had serious chronic health points as defined by APACHE II, and the average APACHE II score prior to ICU admission was 19. Cardiopulmonary resuscitation preceded 34% of admissions and the overall hospital mortality was 58%, although there was no difference in mortality between those who required and those who did not require CPR.
Routine observations were available in 81-89% of cases, basic haematology and biochemistry results in 91% of cases, and blood gases in 51% of patients in the preceding 24 h period to ICU admission. 80% of patients had abnormal heart rate, respiratory rate and oxygenation values as defined by APACHE II. However, only respiratory rate showed a statistically significant rise in APACHE II points over the three time periods.
Seventy-five percent of patients received oxygen within 6 h of ICU entry and the number receiving CPAP doubled over the three time periods, although numbers were small (6.3-12.7%). The use of pulse oximetry also approximately doubled over this time period (36-61%) and worryingly 62.5% of patients had recordings < 90% within 6 h of admission to the ICU.
In this study ward patients admitted to the ICU were seriously ill with a consequent high hospital mortality. Results may have been worse if patients with treatable pathology were included but who died on the wards and never made it to the ICU. Of all the APACHE II variables, an increasing respiratory rate was the best prognostic indicator that ICU admission was required. Ward medical staff were obviously aware that patients were unwell on the wards as reflected by the increasing number of interventions, procedures and additional monitoring received by these patients over the three time periods. Despite this however, one third of patients required CPR prior to ICU admission and perhaps the seriousness of their deterioration was not fully realised.
Seriously ill patients require early assessment by specialists in intensive care medicine, so that initiation of appropriate therapy can prevent a catastrophic deterioration. Abnormalities in certain routinely measured physiological variables may help the inexperienced in deciding when help is required.