Persistent lymphopenia is an independent predictor of mortality in critically ill emergency general surgical patients.

Abstract

Lymphopenia has been associated with poor outcome following sepsis, burns and trauma. This study was designed to establish whether lymphocyte count was associated with mortality in emergency general surgery (EGS) patients, and whether persistent lymphopenia was an independent predictor of mortality. A retrospective review of a prospectively compiled database of adult patients requiring ICU admission between 2002 and 2013 was performed. EGS patients with acute intra-abdominal pathology and organ dysfunction were included. Lymphocyte counts obtained from the day of ICU admission through to day 7 were examined. Multivariate logistic regression models were used to determine the relationship between persistent lymphopenia and outcome. The primary outcome measure was in-hospital mortality. The study included 173 patients, of whom 135 (78%) had a low lymphocyte count at admission to ICU and 91% (158/173) developed lymphopenia on at least one occasion. Lymphocyte counts were lower among non-survivors compared with survivors on each day from day 2 (0.62 vs 0.81, p=0.03) through to day 7 (0.87 vs 1.15, p<0.01). Patients with a persistently low lymphocyte count during the study period had significantly higher mortality when compared to patients with other lymphocyte patterns (64 vs 29%, p<0.01). On multivariate regression analysis, persistent lymphopenia was independently associated with increased in-hospital mortality [odds ratio 3.5 (95% CI 1.7-7.3), p<0.01]. Lymphopenia is commonly observed in critically ill EGS patients. Patients with persistent lymphopenia are 3.5 times more likely to die and lymphopenia is an independent predictor of increased mortality in this patient group.