Timing of onset of intraoperative transfusion anaphylaxis: a literature review.

Clinical diagnosis of intraoperative transfusion anaphylaxis using clinical symptoms is challenging and should be made carefully, as an incorrect clinical diagnosis can exacerbate surgical bleeding secondary to stopping a clinically indicated blood transfusion. The timing of onset of anaphylaxis to start of transfusion may be the key to correctly diagnosing intraoperative transfusion anaphylaxis clinically. However, the reliability of this measure remains unknown. A literature search was conducted using MEDLINE, Embase, the Cochrane Database of Systematic Reviews, and the Cochrane Central Register of Controlled Trials up to June 29, 2021. No language restriction was applied. Two pairs of review authors independently reviewed intraoperative transfusion anaphylaxis cases and extracted data on the timing of onset of anaphylaxis to start of transfusion. A total of 8,918 articles were reviewed, the full texts of 186 articles were assessed, and 20 intraoperative transfusion anaphylaxis cases were included in this study. The 20 intraoperative transfusion anaphylaxis cases included a precise timing of onset. With nine cases, cardiovascular surgery was the most prevalent, and one case was fatal. Fifteen cases had a timing of onset in minutes, and of those, 14 reported timeframes within 30 minutes of initiation of transfusion (median: 15.5, 5-30 minutes). Almost all cases of intraoperative transfusion anaphylaxis occurred within 30 minutes of the transfusion initiation. This timeframe may be helpful in the clinical diagnosis of intraoperative transfusion anaphylaxis.