title: Utility of preoperative in vitro platelet function tests for predicting bleeding risk in patients undergoing functional endoscopic sinus surgery.
abstract: BACKGROUND
  It is necessary to predict the bleeding risk in patients undergoing functional endoscopic sinus surgery (FESS). To evaluate the adequacy of primary hemostasis, preoperative hemostatic screening tests are used. In the present study, we determined whether there is a positive correlation between prolonged closure time (CT) with collagen/epinephrine (CT-epi), prothrombin time (PT), international normalized ratio (INR), activated partial thromboplastin time (aPTT) and bleeding during FESS.
  
  
  METHODS
  We reviewed the medical records of 90 patients without bleeding histories who had undergone FESS from March 2013 to June 2014. More than 200 mL of blood loss was defined as moderate bleeding during surgery. With respect to bleeding during surgery, we determined the sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) of CT-epi, PT, INR and aPTT.
  
  
  RESULTS
  Of the 90 patients, 17 (18.9%) patients had preoperative prolonged CT values and three (17.6%) patients had bleeding. In comparison, five (6.8%) of the 73 (81.1%) patients who had undergone FESS with preoperative normal PFA values experienced bleeding (P=0.171). On the other hand, patients with prolonged PT values (2, 2.2%), prolonged INR values (3, 3.3%) or prolonged PTT values (1, 1.1%) had no bleeding episode. Preoperative CT had low sensitivity (44.4%) and PPV (23.5%).
  
  
  CONCLUSIONS
  During preoperative period, the hemostatic screening may not be helpful to detect the bleeding tendency in adult patients undergoing FESS. Routine measurement of CT-epi, PT, INR and aPTT for preoperative screening may not be recommended for FESS patients.
authors: Department of Laboratory Medicine, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea.
authors: A-Jin
authors: AJ
authors: Lee
authors: Department of Laboratory Medicine, Catholic University of Daegu School of Medicine, Daegu, Republic of Korea.
authors: Sang-Gyung
authors: SG
authors: Kim
keywords: bleeding time; blood coagulation tests; platelet function tests; screening; surgery