The Thai Anesthesia Incidents Study (THAI Study) of oxygen desaturation

Abstract

Objectives: To examine incidents, contributory factors, treatment and outcomes associated with oxygen desaturation during anesthesia practice in Thailand. Material and Method: Relevant data were extracted from the Thai Anesthesia Incidents Study (THAI Study) database between February 1, 2003 and January 31, 2004 and analyzed by using mainly descriptive statistics. Results: Four hundred and ninety seven incidents of oxygen desaturation (SpO2 <90 for at least 3min or £ 85%) were reported. The incidents were widely distributed throughout anesthesia phases. Most of the incidents (92.2%) occurred during general anesthesia, while 23 (4.6%) occurred after regional anesthesia. Anesthesia was the sole contributory factor in 280 patients (56.8%) and a combination of that with other factors in 126 (25.4%). The majority of the incidents (88.4%) was related to respiratory adverse events, whereas, 8% was related to circulatory ones. Sixteen incidents (3.2%) were related to anesthetic machine and equipment failure. Most of the incidents (60.0%) caused minor physiologic changes and were correctable. The management was considered adequate in the majority of patients. As a result, 77.5 % of the patients recovered completely, whereas, death ensued in 5.8%. The cases of death were associated with co-morbidity (ASA class 4 and 5) with an Odds ratio of 12.9 (95% CI:5.4,31.0). The common contributory factors were inexperience, wrong decision, inadequate knowledge and lack of supervision. The proposed corrective strategies included improvement in supervision, care improvement, additional training, clinical practice guideline and quality assurance activity. Conclusion: Incidents associated with oxygen desaturation were distributed throughout all phases of anesthesia. Most of them were preventable and correctable. Therefore, anesthesia care providers should be alert in looking for incidents, and manage them promptly before they were in serious adverse events.