Surgical hemostatic agents: assessment of drugs and medical devices

Surgical hemostatic agents are indicated to improve hemostasis when conventional techniques (compression, sutures or electrocoagulation) are inadequate. The National French Authority for Health (Haute Autorité de santé [HAS]) set out to assess these products (medical devices and agents) to determine their optimal utility. This evaluation included one class of products containing some form of human fibrinogen and thrombin and eight classes of medical devices and automated devices to prepare autologous fibrin. The assessment was based on a systematic review of the literature and expert opinion of health care professionals. The main measures of effectiveness of hemostatic agents were the success rate as expressed in terms of the time necessary to obtain adequate hemostasis, the volume of intra and/or postoperative blood loss, the need for blood transfusions, complication rate, duration of operations and hospital stay. A meta-analysis and 52 controlled randomized studies were selected involving cardiac or vascular surgery (19), ENT surgery (11), gastrointestinal surgery (5), urology (4), orthopedic surgery (4). Approximately half of the studies retained in this analysis evaluated blood derived agents (fibrin sealants) while the other half evaluated medical devices. The working group considered that there is not any evidence that these surgical hemostatic agents decrease the rates of transfusion, complications, reoperation, mortality, duration of operation and/or hospital stay. The working group considered that the use of surgical hemostatic agents to improve the safety of hemostasis in the absence of identified bleeding as an alternative to adequate conventional hemostasis was not justified. Surgical hemostatic agents can be used in ad hoc settings, as a complement to conventional methods to control persistent bleeding after conventional hemostatic techniques, or when abundant bleeding has led to biologic hemostatic disorders. The working group also distinguished several particular settings (mouth and dental care in patients under antiagregant or anticoagulation therapy, central nervous system surgery or acute aortic dissection). Comparative data are insufficient to determine if one product is superior to another for a specific use. To evaluate the clinical value of these products, methodologically sound clinical studies are necessary.