The Relationship of Postoperative Delirium and Unplanned Perioperative Hypothermia in Surgical Patients

Purpose The purpose of this study was to investigate associations between postoperative delirium (POD) and unplanned perioperative hypothermia (UPH) among adults undergoing noncardiac surgery. Design A retrospective, exploratory design was used. Methods A retrospective, exploratory study was conducted using electronic medical record data abstracted from a purposive convenience sample of adult patients undergoing noncardiac surgery from January 2014 to June 2017. Findings The analyzed data set included 22,548 surgeries, of which 9% experienced POD. Logistic regression indicated that American Society of Anesthesiologists (ASA) class was the strongest predictor of POD (χ2 = 1,207.11, df = 4, inclusive of all ASA class terms). A significant relationship between UPH and POD (χ2 = 54.94, df = 4, inclusive of all UPH terms) and a complex relationship among UPH, patient age, ASA class, and POD were also found. Conclusions Results support a relationship between UPH and POD. Notably, there is also a complex relationship in the noncardiac surgery population among UPH, age, ASA class, and POD. Preliminary understanding of this relationship is based on the pathophysiological response to surgical stress. Further research is indicated.