Volume 11 Supplement 3
Acid – base disturbances in critically ill septic patients: a longitudinal quantitative study
© BioMed Central Ltd 2007
Published: 19 June 2007
Applying a quantitative methodology, we described the acid – base status of severe septic patients in the first 5 days after admission to the ICU.
Patients and methods
Patients were studied if they had a diagnosis of severe sepsis with less than 24 hours of organ dysfunction. Data were prospectively collected daily until the fifth day after inclusion.
During the study period, the survivor group presented an increased SBE from -6.4 to -1.5 due to a significant decrease in serum lactate level and SIG. No change occurred in the albumin serum level, which persisted as an alkalinizing force. In contrast, the nonsurvivor group became even more acidemic due to an increase in the PCO2 and persistence of a highly negative SBE. From the metabolic point of view, no significant change occurred in this group from the first to the last day of the study, except for a small increase in the phosphate serum level.
Severe septic patients present, on the first day in the ICU, a complex metabolic acid – base disturbance marked by a mixed high-degree acidosis partially attenuated by a hypo-albuminemic alkalosis. Over the study period, the survivor group partially corrected its acidosis mainly through the disappearance of unmeasured anions and lactate. Nonsurvivors did not change significantly their metabolic acidosis over time.