Objectives: To analyze perioperative stroke and coma using database of Thai Anesthesia Incidents Study (THAI Study) with regard to frequency, contributing factors, preventive and corrective strategies.
Material and Method: Details of perioperative neurological complications comprising stroke and coma in one year were recorded prospectively by attending anesthesiologists or nurse anesthetists in standardized record forms. All data were analyzed to identify contributing factors and preventive strategies.
Results: Among 172,592 anesthetics, there were 24 cases of coma, and 28 cases of stroke. Most cases of coma that eventually died (12/16 cases, 75%) had ASA physical status (ASA PS) ranging from 2E to 5E. Perioperative stroke was found mainly in patients with ASA PS 3 and most of the incidence (74%) occurred in patients who had no previous history of stroke. These patients already had pre-existing cardiovascular diseases and underwent high risk procedures. There were 54% of perioperative stroke cases that could be due to improper cardiovascular management and 42% due to improper emergency neurological management.
Conclusion: The incidence of perioperative stroke and coma in this study was approximately 0.03%. The majority of cases had no prior stroke or coma, which suggested that a problem during perioperative period itself might predispose patients to these complications. Preventive strategies included quality assurance activity, improved communication, and practice guideline.

Keywords: Perioperative stroke, Coma, Anesthesia