Value of nutritional parameters in the prediction of postoperative complications in elective gastrointestinal surgery

The following nutritional parameters were assessed in 117 patients before major gastrointestinal surgery: percentage recent weight loss: percentage ideal body weight; tricipital skinfold; arm muscular area; grip strength dynamometry; serum albumin (ALB); serum transferrin (TFN); delayed hypersensitivity skin tests (DH); total lymphocyte count; prognostic nutritional index (PNI) and clinical assessment of malnutrition. Comparing the results in patients without complications (n = 99) with those in patients with complications (n = 18) and the results in patients who survived (n = 109) with those who died (n = 8), we found that only ALB, DH, TFN and PNI showed significant differences in both comparisons. Correlations of complications with combined parameters was made by multiple linear regression analysis; a modified PNI (mPNI), including these three single variables, has emerged. Considering its risk values, the nutritional parameters showed the following sensitivity and specificity, respectively: ALB less than 3.2 g/dl (72 and 71 per cent), anergy (67 and 64 per cent), TFN less than 205 mg/dl (67 and 55 per cent) and mPNI less than 20 (72 and 70 per cent). Using Bayes' theorems, ALB, DH and calculated indices showed the same predictive capacity and we conclude that single or multiple association of nutritional parameters have no additive effect. To predict complications of nutritional origin it seems only necessary to consider ALB, taking into account the type of operation and the normal duration of postoperative hospital stay without oral intake.