Background and rationale : The purposes of the Thai Anesthesia Incidents Study (THAI Study) of anesthetic outcomes were to survey patients, surgical, anesthetic profiles and determine factors related to adverse events.
Material and Method : A prospective descriptive study of occurrence screening was conducted in 20 hospitals comprised of 7 university, 4 general and 4 district hospitals across Thailand. Anesthesia personnel were required to fill up patient-related, surgical-related, anesthesia-related variables and adverse outcomes on a structured data entry form. The data were collected during the preanesthetic evaluation, intraoperative period and 24 hr postoperative period. Adverse events specific forms were used to record when they occurred. All data were keyed at data management unit with double entry technique and descriptive statistics was used in the first phase of this study.
Results : A total of 163403 consecutive cases were recorded during first 12 months. MD. anesthesiologists involved with 82%, 89%, 45% and 0.2% of cases in university hospitals, regional hospitals, general hospitals and district hospitals respectively. Nurse anesthetists took a major involvement in hospitals run by the Ministry of Public Health. Two-thirds of cases did not receive any premedication (67%) and midazolam was most frequent premedication administered (20%). Common monitoring were non invasive blood pressure (NIBP) (97%), pulse oximetry (96%), electrocardiography (80%), urine output (33%), airway pressure (27%) and capnometry (19%) respectively. The choices of anesthesia were general anesthesia (62%), spinal anesthesia (23%), total intravenous anesthesia (6%), monitor anesthesia care (4%), brachial plexus block (3%) and epidural anesthesia (1%). The adverse events were oxygen desaturation (31.9:10000), cardiac arrest (30.8:10000), death within 24 hr. (28.3:10000), difficult intubation (22.5:10000),re-intubation (19.4:10000), unplanned ICU admission (7.2:10000), coma/cva/convulsion (4.8:10000), equipment malfunction/failure (3.4:10000), suspected myocardial ischemia or infarction (2.7:10000), awareness during anesthesia (3.8:10000), late detected esophageal intubation (4.1:10000), failed intubation (3.1:10000), anaphylaxis or anaphylactoid reaction (2.1:10000), nerve injury (2:10000), pulmonary aspiration (2.7:10000), drug error (1.3:10000), hazard to anesthesia personnel (1.5:10000), unplanned hospital admission (0.1:10000), total spinal block (1.3:10000) and mismatch blood transfusion (0.18:10000)
Conclusion : Respiratory adverse events were common anesthesia direct related events. High incidence of cardiac arrest and death within 24 hr. highlighted concerns for prevention strategies. Incidents of adverse events can be used for institutional quality improvement, educational quality assurance and further research for patient safety in anesthesia.

Keywords : Anesthesia, Complications, Adverse events, Quality, Safety, Outcome