Cardiac arrest during anesthesia at a University Hospital in Nigeria
Background: 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.
Materials and Methods: After obtaining institutional ethics approval, we retrospectively reviewed patients’ hospital records such as anesthetic charts and register and ICU admission charts between 1st July 2005 and 30th 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.
Results: 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%).
Conclusion: 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.
Key words: Anesthesia, cardiac arrest, fatal, nonfatal, outcome