Pre-existing do-not-resuscitate orders are not associated with increased postoperative morbidity at 30 days in surgical patients*

Abstract

To assess the relationship between pre-existing do-not-resuscitate orders and the incidence of postoperative 30-day minor morbidity in surgical patients. Retrospective analysis of prospectively collected data from the American College of Surgeons National Surgical Quality Improvement Program database in patients undergoing general surgical procedures between 2005 and 2008. All U.S. hospitals that participated in the American College of Surgeons National Surgical Quality Improvement Program, which is the nationally validated, risk-adjusted, outcomes-based program that uses a prospective, peer-controlled, validated database to quantify 30-day risk-adjusted surgical outcomes, allowing valid comparison of outcomes among all hospitals in the program. American College of Surgeons National Surgical Quality Improvement Program data included preoperative risk factors, intraoperative variables, and 30-day postoperative mortality and morbidity outcomes for patients undergoing major surgical procedures in both the inpatient and outpatient setting. The data were collected, validated, and submitted by a trained Surgical Clinical Reviewer at each site. Association between do-not-resuscitate status and minor and major morbidities was assessed using proportional hazards models adjusting for death as a competing risk. Of 635,265 patients in the database, 576,745 patients were analyzed. Propensity-matched analysis successfully matched 2,199 (of 2,687 [81.8%]) patients having pre-existing do-not-resuscitate orders (DNR group) with 6,002 non-do-not-resuscitate control subjects (nonDNR group). At any time point within 30 days of surgery, DNR patients were 16% (95% confidence interval, 3-28%; p = .02) less likely to have a minor complication as compared with nonDNR patients after accounting for the competing risk of death. DNR patients were more likely to experience 30-day mortality compared with nonDNR patients (hazard ratio, 2.3; 95% confidence interval, 1.9-2.7; p < .001). However, there was no association between pre-existing do-not-resuscitate orders and occurrence of any major complication (p = .65) treating death as a competing risk event. When associations between do-not-resuscitate orders and individual minor complications were analyzed, a pre-existing do-not-resuscitate order remained independently associated only with decreased odds of superficial surgical site infection (p = .001). Undergoing surgery with a pre-existing do-not-resuscitate order did not increase the risk of having a postoperative minor or major morbidity at any time within the 30-day postoperative period. Results of health care in U.S. hospitals do not differ based on presence of do-not-resuscitate orders.