ABSTRACT: To study characteristics and outcomes associated with emergency response team (ERT) activation in postsurgical patients discharged to regular wards after anesthesia.We identified all ERT activations that occurred within 48 hours after surgery from June 1, 2008, through December 31, 2009, in patients discharged from the postanesthesia care unit to regular wards. For each ERT case, up to 2 controls matched for age (±10 years), sex, and type of procedure were identified. A chart review was performed to identify factors that may be associated with ERT activation.We identified 181 postoperative ERT calls, 113 (62%) of which occurred within 12 hours of discharge from the postanesthesia care unit, for an incidence of 2 per 1000 anesthetic administrations (0.2%). Multiple logistic regression analysis revealed the following factors to be associated with increased odds for postoperative ERT activation: preoperative central nervous system comorbidity (odds ratio [OR], 2.53; 95% confidence interval [CI], 1.20-5.32; P=.01), preoperative opioid use (OR, 2.00; 95% CI, 1.30-3.10; P=.002), intraoperative use of phenylephrine infusion (OR, 3.05; 95% CI, 1.08-8.66; P=.04), and increased intraoperative fluid administration (per 500-mL increase, OR, 1.06; 95% CI, 1.01-1.12; P=.03). ERT patients had longer hospital stays, higher complication rates, and increased 30-day mortality compared with controls.Preoperative opioid use, history of central neurologic disease, and intraoperative hemodynamic instability are associated with postoperative decompensation requiring ERT intervention. Patients with these clinical characteristics may benefit from discharge to progressive or intensive care units in the early postoperative period.