Cardiac arrest during anesthesia at a university Hospital in Nigeria

We assessed the incidence and outcomes of cardiac arrest during anesthesia in the operating room at our university hospital. A previous study on intraoperative cardiac arrests covered a period from 1994-1998 and since then; anesthetic personnel, equipment, and workload have increased remarkably.

After obtaining institutional ethics approval, we retrospectively reviewed patients' hospital records such as anesthetic charts and register and ICU admission charts between 1 st July 2005 and 30 th June 2010. The cardiac arrests encountered during anesthesia was identified from anesthetic charts and followed-up in the intensive care unit (ICU) for the first 24 h postoperatively. We consider that cardiac arrest occurred in any patient under anesthesia with asystole or ventricular fibrillation requiring cardiac compression or electrical defibrillation. We define recovery as an alive and non-comatose patient 24-h after the cardiac arrest.

During the study period, a total of 12,143 surgeries were done; the median age of all the patients was 30 years (range: 1 day-119 years). A total of 31 cardiac arrests identified (frequency 25.5:10,000; 95% confidence interval (CI) 17.7-35.8) out of which 17 were nonfatal. Mortality related to anesthesia was 11.5:10,000 (95% CI 6.5-18.9). The median age of patients with cardiac arrests was 39 years (range: 2 months-78 years). Overall, 80.7% cardiac arrests occurred in the American Society of Anesthesiologists' (ASA) physical status 3-5. Cardiothoracic and neurosurgical operations accounted for 54.8% of the total cardiac arrests. The known risk factors identified among those who had cardiac arrest were, ASA physical status 3-5 (80.7%), procedures performed out-of-work hours (60%), and manually ventilating patients during general anesthesia (39%).

Cardiac arrest during anesthesia is higher in poor risk patients (ASA 3-5) who are manually ventilated under general anesthesia and operated during out-of-work hours.