Sir,

Venous thromboembolism (VTE) is an important cause of death in hospital patients. The House of Commons Health Committee1 reported that around 25 000 people die from preventable hospital-acquired VTE every year. A UK survey suggested that 71% of patients at risk of developing deep vein thrombosis (DVT) did not receive any form of VTE prophylaxis.2 Recent NICE guidance3 did not specifically address ophthalmology patients, but advised to not routinely offer VTE prophylaxis to patients having surgery under local anaesthesia (LA) without limitation of mobility. Although this could include most cataract patients, VR patients due to prolonged operating time/posturing offer a dilemma.

We conducted an electronic survey of BEAVRS over 2 months (June/July 2010). Twenty-four responses were received (response rate 15%, 22 consultants, 1 VR Fellow, 1 trainee with VR interest). A majority of the respondents felt that intra-operative use of VTE prophylaxis was important in high-risk patients (30% for cases under LA and 56% for those under a general anaesthetic (GA)). None felt that post-operative VTE prophylaxis should be used routinely in all patients who are posturing, with 60% advocating use only in high-risk patients based on NICE guidance. To reduce VTE risk, 57% were advised frequent leg exercise while immobile, 44% good hydration, and 91% a 10-min mobilising break every hour. In all, 17% had, on occasion, sent patients home with anti-embolic stockings, but none had arranged for monitoring of complications; 75% did not have specific departmental guidelines, while 8% did not know if any existed; 33% stated that there were routine checks for indications/contra-indications to anti-embolic stockings in pre-assessment clinics, while 21% did not know; 26% of the respondents' VR procedures were under GA.

Although a longer running survey might have yielded a higher response rate, we felt that time limiting it would indicate the VR community's interest. Guidance which has become available from RCOphth4 states that VTE risk assessment should be undertaken on any patient over the age of 60 undergoing a procedure under GA. This will also be required for long procedures under LA, where the patient is required to lie still for the duration of the procedure (eg, major VR procedures). All VR patients will thus need VTE risk assessment. As there are no national exemption criteria, all exemptions will have to be negotiated locally by the VR surgeon and approved by the Trust Medical Director/Strategic Health Authority Medical Director.