The value of routine preoperative testing in the prediction of operative hemorrhage in adenotonsillectomy.

Medical records were reviewed to identify subjects who ranged in age from 1 to 18 years and who had undergone tonsillectomy with or without adenoidectomy. Data obtained included patient demographic information, relevant medical history, history of hemorrhage, family history of hemorrhagic disorders, and drug history. Laboratory data obtained included a baseline coagulation screening to determine prothrombin time, activated partial thromboplastin time, and platelet count. Values were classified as within normal limits or as abnormally prolonged according to the local laboratory reference values. The incidence of postoperative hemorrhage in healthy subjects was evaluated, and the correlation between having a medical history of hemorrhage and an abnormal coagulation screen was assessed. We found that the medical history of the patients studied had positive predictive value of 42.8%, and a negative predictive value of 99.1%. The preoperative coagulation screening had a positive predictive value of 50%, and a negative predictive value of 93.6%.