UK cataract dataset audit reveals medications more likely to cause complications during surgery

Clopidogrel and warfarin are associated with a significant increase in minor complications of sharp needle and subtenon’s cannula local anaesthesia but are not associated with sight-threatening complications, according to a study published online ahead of print by Eye.

Robert Johnson from the Gloucestershire Eye Department, Cheltenham General Hospital, UK, and colleagues carried out a study to establish the prevalence of aspirin, dipyridamole, clopidogrel and warfarin use in patients undergoing cataract surgery and to compare local anaesthetic and intraoperative complication rates between users and non users. The Cataract National Dataset was extracted and anonymized on 48,862 operations at 12 National Health Service (NHS) Trusts using electronic patient records between 2001 and 2006.

In all, 28.1% of patients were taking aspirin, 5.1% warfarin, 1.9% clopidogrel and 1% dipyridamole. The incidence of any complication of a sharp needle or subtenon’s cannula local anaesthetic block was increased in patients taking clopidogrel (8%, p<0.0001) or warfarin (6.2%, p=0.0026) versus non-users. However, there was no increase in potentially sight-threatening complications. The incidence of subconjunctival haemorrhage was also increased in patients taking clopidogrel (4.4%, p<0.0001) or warfarin (3.7%, p<0.0001) versus non-users. The recording of operative complication was increased in those taking clopidogrel (7.3%, p=0.0002) versus non-users but the haemorrhagic operative complications of choroidal/suprachoroidal haemorrhage and hyphaema were not significantly increased.

The authors concluded that there is a significant increase in minor complications in cataract surgery patients taking clopidogrel and warfarin.