RESUMO
Tissue injury and infection leads to local production of interleukin-6 and other cytokines that mediate most of the systemic aspects of inflammation. We conducted this study to 1-Evaluate the effect of hepatic cirrhosis on the time course of acute phase proteins [APPs] following major surgery; and 2- Assess this effect in confirming or refuting the suspicion of postoperative infection in these patients during their stay in the surgical intensive care unit [SICU]. We prospectively studied 40 patients scheduled for major abdominal surgery, of whom 21 were non-cirrhotic [control group] and 19 had either known history or clinical evidence of hepatic cirrhosis [study group]. Central venous samples were obtained from all patients for laboratory assessment at induction of anaesthesia, at the end of surgery and at 24 h, 48 h and 72 h postoperatively [PO]. On the fourth PO day, patients from both groups were categorized into infected and non-infected sub-groups [using criteria of Centers for Disease Control] and another blood samples were obtained Laboratory assay: the collected blood samples were analyzed for the serum levels of APPs namely: interleukin-6 [IL-6], C-reactive protein [C-RP], serum amyloid A [SAA] and serum albumin. Liver functions were also assessed by serum concentrations of alanine aminotransferase [ALT], lactic dehydrogenase [LDH], total bilirubin [TB] and prothromhin time [PT]. IL-6 reacted fast in non-cirrhotic patients and reached a peak concentration at 2 h PO [400 +/- 122 pg.ml[-1], P<0.001]. In cirrhotic patients, the reaction of IL-6 was delayed and peak concentrations were not achieved except at 48 h PO [220 +/- 72 pg.ml[-1], P<0.001]. Sera levels of IL-6 were significantly lower in cirrhotic as compared with non-cirrhotic patients at 2,24,48 and 72 hrs PO. C-RP and SAA increased slower and later than IL-6. In both groups, peak concentrations of C-RP and SAA were recorded at 48 and 72h PO, respectively. Serum concentrations of CRP and SAA were not significantly different between the 2 groups throughout the study period [P >0.05]. Serum albumin levels in cirrhotic patients were significantly lower than those in non-cirrhotic at all measured times [P<0.05]. On the fourth postoperative day, patients who developed infection showed significantly higher serum IL-6 levels as compared with non-infected patients in both cirrhotic and non-cirrhotic patients. Serum albumin levels in patients who developed PO infection were significantly lower compared with non-infected patients in both groups. PO infection rate correlated positively with serum IL-6 concentrations and negatively with serum albumin levels in both cirrhotic and control groups. The serum concentrations of C-RP and SAA were not significantly different between infected and non-infected patients of either group [P>0.05]. ALT, LDH, TB and PT were higher in cirrhotic as compared with non-cirrhotic patients at all times [P<0.01], but did not differ significantly between infected and non-infected patients of either group. Major surgery causes substantial increase of the plasma concentrations of APPs in both cirrhotic and non-cirrhotic patients. Among the studied parameters, IL-6 showed the most rapid change, and appears to be a good marker for the early detection of acute phase reaction. Both IL-6 increase and albumin decrease correlated well with postoperative infection rate, and may be used as early predictors of sepsis in these groups of patients