Lactate as a Predictor in Severe Pneumonia

Abstract

Introduction. There are many discussions that one of the mortality risk markers for patients admitted to intensive care unit (ICU) with different etiology shock is admission blood lactate level. It is believed that serum lactate could be used as an early marker of mortality risk determination. We are not aware about research studies regarding admission serum lactate prognostic significance in patients with severe community acquired pneumonia (CAP) in first 24 hours after admission to ICU in Latvia.Aim of the study. 1. To evaluate the prognostic significance of the first lactate level in patients with severe pneumonia. To compare the statistical data of different blood lactate levels (LAC 1 , LAC 2 , LAC 3 , LAC 4 , LAC MAX , LAC MIN ). 2. To find admission lactate reference level which is attributed to significant increase of mortality.3. To compare with other markers and scoring systems like: PCT (procalcitonin), CRP (C-reactive protein), CURB-65 (pneumonia severity score), APACHEII (Acute Physiology and Chronic Health Evaluation II).Material and methods. This is a retrospective observational study in which data were collected on all patients admitted to ICUwith pneumonia and sepsis and/or septic shock in two major Hospitals of Republic of Latvia (Eastern Clinical university hospital and Pauls Stradins Clinical university hospital) with primary diagnosis of severe community acquired pneumonia (CAP). We compared the relationship between lactate values that were collected in 24 hour period after admission in ICU and ICU mortality. Results. In this study we analyzed data from consecutive 73 patients with severe CAP and sepsis and/or septic shock and we observed statistically significant difference between the first lactate level (LAC 1 ) in survivors (2.7 [1.9-3.2] (mmol/l) and non-survivors 4.9 [4.3-7.5] (mmol/l); p<0.001).According to data patients with LAC 1 <3.0 (mmol/l) mortality risk was 0%, patients with LAC 1 3.0 - 4.0 (mmol/l) risk was 42.1%, while patients with LAC 1 >4.0 (mmol/l) mortality risk reached 89.7%. Lactate level measurements in first 24 hours after arrival into the ICU have had high ability to stratify non-survivor patients: LAC 1 (0.96), LAC 2 (0.98), LAC 3 (0.97), LAC 4 (0.92), (AUC). Incomparison with other prognostic markers sensitivity and specificity following results were obtained: CRP (0.59), PCT (0.98), APACHE II (0.98), CURB-65 (0.63). Conclusions. Summarizing data on patients with severe pneumonia and sepsis and/or septic shock admission lactate in first 24 hours have significant independent predictive value. In first 24 hours after admission in ICU higher mortality were observed if LAC 1 was >3 (mmol/l). Data proves for the patients with severe pneumonia LAC 1 is having similar prognostic ability like APACHEII and PCT, and significantly better prognostic ability than CRP and CURB-65.