Objective: To determine the incidence and time sequence of mortality and major morbidity after ambulatory surgery.
Design: Prospective outcome survey of patients at 16 to 72 hours and 30 days after their surgical procedures.
Setting: A tertiary care rural referral center providing ambulatory care.
Patients: A total of 38,598 patients aged 18 years and older undergoing 45,090 consecutive ambulatory procedures and anesthetics. Contact rates for 72 hours and 30 days were 99.94% and 95.9%, respectively.
Main outcome measures: Mortality and major morbidity incidences, including myocardial infarction, central nervous system deficit, pulmonary embolism, and respiratory failure.
Results: Thirty-three patients either experienced major morbidity or died (1:1366 [proportional risk]). Four patients died (1:11,273), two of myocardial infarction and two in automobile accidents. No patient died of a medical complication within 1 week of surgery. Of the 31 patients who developed a major morbidity (1:1455), 14 (45%) had myocardial infarction (1:3220), seven (23%) had a central nervous system deficit (1:6441), five (16%) had pulmonary embolism (1:9018), and five (16%) had respiratory failure (1:9018). Four events (13%) occurred within 8 hours of surgery (1:11,273), 15 (48%) in the next 40 hours (1:3006), and 12 (39%) in the next 28 days (1:3758).
Conclusion: In this ambulatory surgical population, more than one third of major morbidity occurred 48 hours or later after surgery. Overall morbidity and mortality rates, however, were very low.