LAUSR

Venous thromboembolism (VTE), which includes both deep vein thrombosis (DVT) and pulmonary embolism (PE), is an important complication relating to hospital admission. VTE carries a high burden of morbidity and mortality; as such, the UK National Institute for Health and Care Excellence (NICE) has, over the last decade, made it a priority to reduce its incidence. There are two principal approaches to VTE prophylaxis: mechanical lower limb compression with stockings or intermittent pneumatic compression devices (IPCD); and pharmacological prophylaxis usually with subcutaneous injection of low molecular weight heparin (LMWH). Following VTE risk assessment, mechanical and pharmacological approaches are often used in combination for at risk hospital in-patients as recommended by the most recent NICE guidelines. Every year in the UK National Health Service (NHS) millions of patients are prescribed graduated compression stockings (GCS). The annual cost of buying and applying GCS was, in 2017, estimated at £63.1 million for surgical patients in England alone. If also considering the use of GCS in Scotland, Wales and Northern Ireland, the use of GCS outside of surgery, up to date costs of GCS in 2020, and the likelihood that patients will require more than one pair of GCS to be provided and applied during a hospital stay, it is clear that the £63.1 million per annum recurring cost is a conservative reflection of the financial impact of GCS to the NHS. Aside from cost, and importantly, the efficacy of thromboprophylaxis with GCS has been called into question. CLOTS 1 was the first recent randomised control trial (RCT) to raise doubts regarding thromboprophylaxis with GCS. In 2009, the CLOTS 1 investigators reported that, in stroke patients, wearing GCS in combination with LMWH prophylaxis conferred no significant absolute reduction in the risk of developing a DVT compared to controls (who received pharmacological prophylaxis alone). In fact, there was a significant increase in skin breaks, ulcers, blisters and skin necrosis in those randomised to wearing GCS. A subsequent systematic review concluded that – in surgical patients – the existing literature did not offer clarity as to the additional benefit of wearing GCS in combination with LMWH injection compared to sole pharmacological therapy, and recommended further clinical trials to directly evaluate this clinical question. The GAPS RCT is the most recent study to examine the efficacy of mechanical thromboprophylaxis with GCS in patients receiving pharmaco-thromboprophylaxis. It has demonstrated that in elective surgical patients who were risk-assessed as medium or high-risk for VTE (but not requiring prophylaxis beyond inpatient admission), prophylactic dose LMWH alone was not inferior to the combination of LMWH and GCS. Furthermore, although the evidence for the use of IPCDs for thromboprophylaxis has been considered more robust than that for GCS, the PREVENT RCT reported no significant VTE risk reduction associated with their use in a critical care setting (thus a mixed population of surgical and medical patients), when pharmaco-thromboprophylaxis was received. Although not directly comparable, the CLOTS-3 RCT did report with the use of IPCD in a stroke patient cohort a significant absolute reduction in risk of DVT by 3.6%; almost a quarter of patients included had received some form of background pharmacological anti-coagulation (prophylaxis, treatment or thrombolysis). Finally, in regard to IPCDs, a recent meta-analysis of their use as an adjunct to pharmacological thromboprophylaxis demonstrated a modest risk reduction of VTE compared to pharmacological therapy alone in surgical patients. However, this effect was not reproduced in medical patients.