Resuscitation of people with a do-not-resuscitate order: When does it happen and what are the outcomes?

Background: Do-not-resuscitate (DNR) orders allow competent individuals to state their wishes to not receive resuscitation. Despite the existence of a DNR order, resuscitative efforts may still occur. Methods: The statewide out-of-hospital cardiac arrest (OHCA) registry in Victoria, Australia (population 6.5 million) identified rates of DNR orders and resuscitative efforts in >= 60-year-olds from 2006-2021. Results: Of 47,322 patients >= 60 years old with OHCA, 2,688 (5.7%) had a DNR order. DNR order was communicated to emergency call-takers in only 332 (12.4%) cases. Bystander resuscitation was commenced in 1,074 (40.0%) patients, with EMS terminating efforts in 346 (32.2%) patients on arrival but commencing resuscitation in 189 others. Strongest predictors of bystander resuscitation were shockable rhythm (OR 7.75, 95% CI 5.04- 11.9) and OHCA in public location (OR 4.8, 95% CI 2.0-11.3). Predictors of EMS terminating resuscitation efforts were OHCA in residential aged care facility (OR 1.93, 95% CI 1.47-2.5) and older age (OR 1.02, 95% CI 1.00-1.04). Transfer to hospital was undertaken in 107 patients, with stron-gest predictors being return of spontaneous circulation (OR 91.1, 95% CI 51.7-160.7) and witnessed OHCA (OR 7.5, 95% CI 3.9-14.5). Only 7 (0.3%) transported patients survived to discharge, with 5 deceased at 12-month follow-up. Conclusion: Approximately 5% of EMS-attended OHCAs in >= 60-year-olds involve a patient with a DNR order, with low rates of awareness of DNR orders. Resuscitation is commenced in 47% of patients, and 4% are transported to hospital with very poor outcomes. Strategies to communicate DNR status and respect patients' autonomy are extremely important.