Low Incidence of Thrombosis in Hemophilic Patients Undergoing Surgeries or Invasive Procedures,
Authors: Feng Yan , Carcioppolo Desiree , Lichtin Alan E. 
Published: October 2019

Abstract
Abstract 4221

BACKGROUND AND OBJECTIVE:
The major concern for hemophilic patients who undergo surgery is bleeding, and they usually receive factor replacement. Since surgery is a well known risk factor for venous thrombosis, non-hemophilic patients frequently receive DVT prophylaxis in post-op period. However the risk of venous thrombosis in hemophilic patients who undergo surgery is rarely studied or reported. We observed a patient with severe hemophilia B who developed extensive DVT after open heart surgery when he was receiving factor IX replacement. This prompted a retrospective chart review study to evaluate the risk of DVT in hemophilia patients who undergo surgery or invasive procedure.

SUBJECTS AND METHOD:
A total of 154 patients who received factor VIII or IX replacement from Feb. 1997 to June 2011 at Cleveland Clinic were identified by searching the pharmacy database. A total of 38 patients who underwent 58 elective surgeries were finally included in the analysis. Patients who had surgery for bleeding were excluded

RESULTS:
All patients are male, except one female hemophilic carrier. Patients' age at surgery varied from 9 months to 85 years with median age 48 years. Twenty seven patients (71%) had factor VIII deficiency with baseline level 1%-31% (median 5%, 25th to 75th 2%-12%). Eleven patients (29%) had factor IX deficiency with baseline level 2%-36% (median 5%, 25th to 75th 3%-8%). Thirteen patients had more than one surgery at Cleveland Clinic. Out of these 58 surgeries/procedures in these 38 patients, 15 were orthopedic, 10 open heart, 10 abdominal (including liver and kidney transplant), 5 neurosurgery, 2 head and neck and 16 other surgery (including 3 vascular procedures). The factor replacement duration was 1–19 days (median 8 days, 25th to 75th5 to 9 days). The median trough level was 97% (25th to 75th77% to 130%). Eighteen (31%) patients had post-op bleeding defined as requiring surgical intervention or more than 1 unit blood transfusion. One patient received subcutaneous heparin for DVT prophylaxis from day 2 after his head/neck surgery and did not experience any episodes of bleeding or DVT. Six patients (5 with open heart surgery and one with carotid endarterectomy) received aspirin post-operatively (one with clopidogrel and one with warfarin on discharge) and two of them experienced bleeding (both had mild thrombocytopenia and one had trough factor IX level 55%). One patient had one episode of TIA on the next day after total knee replacement (his trough level was 98%). Only one patient had DVT after surgery. He was a 72 year old male with hemophilia B (factor IX baseline level 5%) who underwent an open heart surgery (1 vessel CABG, mitral valve repair and pulmonary vein isolation). He did have history of renal thrombosis when he was on factor IX concentrate replacement twenty years ago. He was started with recombinant factor IX twice daily before his open heart surgery, and dose adjusted based on trough level, which was maintained near 100%. On post-op day 5, he developed an occlusive DVT extending from the right internal jugular vein to median cubital vein, where he had a temporary central line placed post-op. He was ambulatory but not on aspirin or DVT prophylaxis. He was anticoagulated with heparin which was subsequently converted to warfarin, along with factor IX infusion. He did well and was discharged home on post-op day 14.

CONCLUSION:
We found two thrombotic events (DVT and TIA) in this retrospective study (3.4%). Had routine prophylactic anticoagulation been given to all patients, a higher incidence of bleeding could be anticipated. This study therefore supports the position of not giving routine prophylactic anticoagulation to hemophilic patients undergoing surgery, unless there is previous history of excessive thrombosis with factor replacement.

Disclosures:
No relevant conflicts of interest to declare.