Background: The red blood cell distribution width index (RDW) is one of several parameters routinely analysed in peripheral blood counts. The aim of the study was to assess the usefulness of RDW in the prediction of in-hospital mortality in patients undergoing high-risk gastroenterological surgery.
Methods: Prospective observation covered 229 patients who underwent surgery, for whom the risk of cardiovascular complications was high due to the type of procedure. The patient’s individual risk was assessed using the criteria of the American Society of Anesthesiologists (ASA-PS). Peripheral blood for morphological examination was collected preoperatively. The following parameters of the red blood cell system were evaluated: red blood cell count (RBC), haemoglobin (Hgb), haematocrit (Hct), mean corpuscular volume (MCV), RDW expressed as a standard deviation (SD) and a coefficient of variation (CV). The occurrence of hospital death was the main endpoint.
Results: Patients who died had had statistically significantly lower RBC, Hgb and Hct values, as well as higher RDWSD and RDW-CV values. Both the preoperative RDW-SD and RDW-CV values predicted the outcome, respectively: AUC RDW-SD = 0.744 (95% CI: 0.683–0.799; P < 0.001), AUC RDW-CV = 0.762 (95% CI: 0.702–0.816; P < 0.001). In logistic regression, it was confirmed that RDW predicted mortality (OR RDW-SD = 1.21; P < 0.001, OR RDW-CV = 1.62; P = 0.01), even after adjustment for individual risk and other erythrocyte parameters.
Conclusion: RDW is a valuable screening predictor of in-hospital mortality in patients undergoing high-risk gastroenterological surgery, regardless of the estimated individual risk and the value of other erythrocyte parameters. Evaluation of the RDW may be helpful in the identification of patients requiring correction of haematological disorders in the pre-operative period, as well as, in particular, surveillance in the perioperative period.
Keywords: peripheral blood morphology; anaemia; risk; perioperative medicine.