The use of two nutritional indicators in identifying long bone fracture patients who do and do not develop infections

One hundred consecutive orthopedic long bone fracture patients requiring surgical fixation were nutritionally assessed using both the nutritional index of Rainey-MacDonald et al. and total lymphocyte count. The ability of these two parameters to identify correctly those patients who do and do not develop postoperative complications was assessed using several error rate measures, which included sensitivity, specificity, positive predictive value, negative predictive value, and accuracy. Fourteen of our patients developed postoperative complications. All complications observed were infections. The accuracy of the nutritional index and total lymphocyte count in predicting patient outcome was 78 and 51%, respectively. The positive and negative predictive values calculated for the nutritional index were 36 and 94%, respectively. Total lymphocyte count analysis resulted in positive and negative predictive values of 15 and 87%, respectively. In our sample of patients, the nutritional index was a better predictor of patient outcome than total lymphocyte count, as indicated by the higher accuracy rate calculated for the nutritional index. Based upon positive predictive value results, neither of these indicators was most accurate in identifying patients who did develop infections. Not unexpectedly, both indicators were best in identifying those patients who did not develop postoperative infections.