Postoperative inflammatory responses and association with in-hospital mortality after general surgery

Background: The relationship between postoperative in-hospital mortality and inflammatory markers has not been well described. This study aimed to characterize the association between specific clinical markers of inflammation and in-hospital mortality in the early postoperative period in general surgical patients. Methods: This study included consecutive general surgery admissions at two tertiary hospitals in South Australia over a 2-year period. Collected data included patient demographics, Charlson comorbidity index, in-hospital mortality, vital signs, and laboratory tests. In particular, temperature, neutrophil count, lymphocyte count, platelet count, albumin level, and C-reactive protein (CRP) were collected for the 48 h after surgery. Multivariable logistic regression was conducted to examine the association between clinical inflammatory markers and in-hospital mortality in the first 24 h postoperatively and 24–48 h postoperatively. Results: 5493 patients were included, with an average age of 52.8 (SD 19.4). 2548 (46.4%) were female, and 53 (1.0%) experienced in-hospital mortality. In the first 24 h postoperatively, temperature >38°C, neutrophil count >14 × 10⁹/L, and a lymphocyte count >5 × 10⁹/L were significantly associated with an increased likelihood of in-hospital mortality, whereas platelets, albumin, and CRP during were not. Between 24 and 48 h postoperatively, increases in maximum neutrophil counts, lymphocyte counts, and platelet counts were significantly associated with an increased likelihood of in-hospital mortality, whereas changes in temperature, albumin, and CRP were not. Conclusions: This is the first study to characterize the inflammatory response using specific clinical laboratory markers, and their relative association with in-hospital mortality, in the first 2 days after general surgery.