Serum Lactate Level As A Predictor Of Outcome In Respiratory Intensive Care Unit Patients

Abstract

Aim: The objective of the current study is to find out and correlate the predictive value of serum lactate
level in the first 12h of ICU admission regarding mortality and length of ICU stay. Methods: Thirty-seven
critically ill patients were enrolled. All patients’ functional conditions were assessed on admission by the
Acute Physiology and Chronic Health Evaluation (APACHE-IV), scoring system, Glasgow Coma Scale
(GCS), Three samples of lactate were obtained. One on admission, one after 6 h and one after 12 h of
admission. Results: Patients’ in-hospital mortality was 12/37 (32.4%), Serum lactate in the three samples
was shown to be significantly accurate in predicting non survivors, average blood lactate level were
significantly (P<0.0001) high in deceased patients compared to survivors. Elevated levels had high notsurvivors discriminative power (ROCAUC=0.945 [95%CI 0.89-0.99]; P<0.0001). Blood lactate <4mmol/L
had a higher survival probability with statistically significant difference compared to patients with
increased blood lactate >4mmol/L (P<0.0001). Cox regression analysis revealed that only blood lactate was
an independent mortality predictor (AHR 20.1 [1.5-270.0], P=0.025). Conclusions: Non survivors had
higher blood lactate levels at admission as well as at 6 and 12 h. Average blood lactate levels after 12 hours
of ICU admission is a good prognostic marker and gives valuable information in initial critically ill patient
evaluation.