Actualizing complex issue of venous thromboembolism prophylaxis in obese population

Regardless of the fact that obesity has been recognized as a prominent risk factor for venous thromboembolism (VTE), neither the latest 2012 guidelines nor those earlier ones, though specifying it, do not elucidate sufficiently the intricate issue of thromboprophylaxis in the obese. Yet, a number of studies point out that the fixed dose anticoagulant therapy recommended for the general population is suboptimal in obese patients, primarily due to pharmacokinetics complexity in this patient group. Both disturbed subcutaneously administered drug absorbtion from poorly vascularised subcutaneous fat mass tissue and a lower proportion of highly-vascular lean body mass as a part of total body weight, inter alia, consequently increasing the risk for overdose of anticoagulants because of simplified dose calcuation based on total body weight represent only a segment of the problem. The problem is further aggravated by the fact that the absolute drug clearances and glomerular filtration rate in the obese are higher as well as possible influence on certain hepatic metabolic processes and drug-specific volume distribution. The existing range of subcutaneous low-molecular weight and unfractioned heparin and FXa selective antagonist dosing regimens in obese patients well indicate the contraversy of VTE prophylaxis as well as the problematic validity of these drugs monitoring by the use of standard assays. An alternative solution would involve the low - dose intravenous unfractioned heparin infusion administration, introduction of vitamin K antagonist type of oral anticoagulant simply monitored by INR and indispensible VTE mechanical prophylaxis tailored to the needs of this population.