Incidence Of Fibrin Related Unfolding Problems Before And After The Use Of Enoxaparin Infusion For Descemet Membrane Endothelial Keratoplasty (Dmek)

Compare intraoperative and consecutive follow up complications before and after introduction of enoxaparin to balanced salt solution. Intraoperative: fibrin formation, iris prolapse and difficult unfolding of graft. Post operative: need for re-bubbling, graft failure.

All surgeries were performed in Frimley Park Hospital (FPH) by 5 surgeons over period of 4 years. Donor material was supplied by NHSBT until 2023, and since supplied by NHSBT and now imported from USA (Optisol). Enoxaparin was first introduced into 500 ml balanced salt solution in FPH in January 2024.It is an injectable low molecular weight heparin which offers both anti-inflammatory and anti-thrombotic effects and a lower risk of bleeding which is both time- efficient and cost-effective

Retrospective review of electronic patient records (EPIC, Medi sight). Cases of DMEK done between 2021-2024 with and without enoxaparin were taken for review. Demographics, indications for surgery, intraoperative and post operative complications were collected.

Total 77 DMEK. 39 without (Group 1) and 38 with enoxaparin (Group 2). Major indication was Fuchs’ in both groups. Average age was 70,female. Most were performed alone however 7 in group 1 and 11 in group 2 were combined with Phaco. In group 1, in 4, donor graft got stuck due to fibrin formation leading to difficult unfolding and eventually graft failure requiring second surgery. In group 2, no cases had difficult unfolding however in 2 ,there was primary graft failure despite uneventful surgery requiring second surgery. 4 in group 1, had iris prolapse and trace fibrin however graft unfolded well after manipulation with final good position compared to 2 in group 2. 4 in group 1 required re-bubbling and repositioning compared to 3 in group 2.

Fibrin formation during DMEK surgery is an uncommon but challenging complication that can make graft manipulation difficult, however the result of this audit shows that addition of enoxaparin to the irrigating solution can facilitate unfolding of DMEK graft and reduce fibrin formation.