Developing models to predict early postoperative patient deterioration and adverse events

Background: Accurate identification of patients at risk of early postoperative deterioration allows needs-based allocation of patients to appropriate levels of care. This study aimed to record the incidence of early postoperative deterioration and identify factors predictive of at-risk patients. Doing so may assist future evidence-based perioperative planning and allocation of patients to high-acuity facilities. Methods: With ethical approval, data from elective non-cardiac surgical patients were collected between May and August 2013. Patient and surgical factors potentially related to postoperative deterioration were collected from preoperative assessment records. Data on deterioration in the postanaesthesia care unit (PACU), and on the wards were collected prospectively for a period of 72 h postoperatively. Patient factors, surgical factors and PACU events were compared with ward events using binomial logistic regression analysis. Results: Of the 747 patients, postoperative deterioration was common both in PACU (155 (20.1%) patients) and on the wards (125 (16.7%)). Common ward events included hypotension (64 (8.2%)) and desaturation (59 (6.2%)). A rapid response team call occurred for 33 (4.4%) patients and an unplanned ICU admission for seven (0.9%) patients. A history of atrial fibrillation and chronic liver disease, duration of surgery and excessive sedation in PACU, among others, were strongly associated with subsequent ward deterioration. However, measures of surgical complexity were not. Conclusions: Patient factors, duration of surgery and events in PACU can be predictive of subsequent early postoperative ward clinical deterioration. Such information may aid appropriate perioperative decision-making with respect to postoperative utilization of high-acuity facilities.