Physiological stress level and screening for malnutrition as preoperative predictors of postoperative complications in pancreatic surgery: a retrospective study.

Background: Assessment of 'physiological stress levels' and 'nutritional status' before surgery is important for predicting complications and indirect interventions on the pancreas. The aim of this study was to determine neutrophil-lymphocyte ratio (NLR) and nutritional risk index (NRI) indicators before surgery to predict 90-day complications and mortality in a cohort of patients with complicated chronic pancreatitis and cancer of the head of the pancreas.

Methods: We evaluated preoperative levels of NLR and NRI among 225 subjects treated at different centres located in three countries. Short-term outcomes included length of hospital stay, postoperative complications, and mortality at 90 days and were appreciated based on NLR and NRI. The level of physiological stress was divided according by the formulas: neutrophil-lymphocyte ratio (NLR) = (neutrophil count, %)/(lymphocyte count, %). The nutritional state of the patients was divided according to the INR: NRI = (1.519 × serum albumin, g/L) + (41.7 × present weight, kg / usual weight, kg)].

Results: All patients were operated. An analysis of the operations performed in three institutions demonstrated mortality in chronic pancreatitis and pancreatic pseudocysts in 1.4%, in chronic pancreatitis and the presence of an inflammatory mass mainly in the pancreatic head in 1.2%, and in cancer of the pancreatic head in 5.9%. The mean preoperative NLR was normal in 33.8% of the patients, the mild physiologic stress level was 54.7%, and the moderate was 11.5% before surgery. 10.2% of patients had a normal nutritional status, 20% had mild, 19.6% had moderate, and 50.2% had severe malnutrition. In a univariate analysis, at the cutoff of NLR ≥ 9.5 (AUC = 0.803) and the cutoff of NRI ≤ 98.5 (AUC = 0.801), increasing the risk of complications was observed (hazard ratio, 2.01; 95% CI, 1.247-3.250, p = 0.006), but at the cutoff of NRI ≤ 83.55 (AUC = 0.81), we observed a survival difference in operated patients (hazard ratio, 2.15; 95% CI, 1.334-3.477, p = 0.0025).

Conclusions: Our study demonstrated that NLR and NRI were predictors of postoperative complications, but only NRI was a predictor of 90-day mortality in patients after surgery.