The use of perioperative antithrombotics in posterior segment ocular surgery

Perioperative Considerations for Antithrombotic Therapy in Oculofacial Surgery: A Review of Current Evidence and Practice Guidelines

PURPOSE

Recent survey studies have demonstrated wide variability in practice patterns regarding the management of antithrombotic medications in oculofacial plastic surgery. Current evidence and consensus guidelines are reviewed to guide perioperative management of antithrombotic medications.

METHODS

Comprehensive literature review of PubMed database on perioperative use of antithrombotic medication.

RESULTS/CONCLUSIONS

Perioperative antithrombotic management is largely guided by retrospective studies, consensus recommendations, and trials in other surgical fields due to the limited number of studies in oculoplastic surgery. This review summarizes evidence-based recommendations from related medical specialties and provides context for surgeons to tailor antithrombotic medication management based on patient's individual risk. The decision to continue or cease antithrombotic medications prior to surgery requires a careful understanding of risk: risk of intraoperative or postoperative bleeding versus risk of a perioperative thromboembolic event. Cessation and resumption of antithrombotic medications after surgery should always be individualized based on the patient's thrombotic risk, surgical and postoperative risk of bleeding, and the particular drugs involved, in conjunction with the prescribing doctors. In general, we recommend that high thromboembolic risk patients undergoing high bleeding risk procedures (orbital or lacrimal surgery) may stop antiplatelet agents, direct oral anticoagulants, and warfarin including bridging warfarin with low-molecular weight heparin. Low-risk patients, regardless of type of procedure performed, may stop all agents. Decision on perioperative management of antithrombotic medications should be made in conjunction with patient's internist, cardiologist, hematologist, or other involved physicians which may limit the role of guidelines depending on patient risk and should be used on a case-by-case basis. Further studies are needed to provide oculofacial-specific evidence-based guidelines.

Haemorrhagic complications following cataract and vitreoretinal surgery with sub-Tenon's block in patients receiving non-vitamin K oral anticoagulant agents: A prospective audit

There is a lack of data to support either continuation or interruption of non-vitamin K oral anticoagulants for cataract and vitreoretinal surgery. A prospective audit was undertaken of 291 patients undergoing cataract surgery or vitreoretinal surgery, predominantly under sub-Tenon's block, while continuing these agents. The median time from last non-vitamin K oral anticoagulant dose to the insertion of sub-Tenon's block was five hours. No patient required emergency reversal of anticoagulation. There were no sight-threatening complications in the immediate perioperative period, although two vitreoretinal patients (3.8%) had a moderate haemorrhagic complication on day five, and two cataract patients (0.8%) had a minor haemorrhagic complication on days one and 14 postoperatively. Despite continuing their non-vitamin K oral anticoagulants, three (1%) cataract patients had a moderate thromboembolic complication within the 30-day postoperative period. The risk of haemorrhagic complications associated with continuation of anticoagulation with non-vitamin K oral anticoagulants for cataract and vitreoretinal surgery is low, and this audit supports the continuation of non-vitamin K oral anticoagulants for our patients having cataract and vitreoretinal surgery.

Randomised controlled trial on vitreoretinal surgery with and without oral anticoagulants: surgical complications, visual results and perioperative thromboembolic events

BACKGROUND

Vitreoretinal surgery in anticoagulated patients is a challenging situation for vitreoretinal surgeons, who have to choose between being faced with the systemic thromboembolic risks that the interruption of anticoagulation involves, or the intra- and postoperative haemorrhagic risks associated with maintenance of this therapy. So far, no trial has compared, in a prospective and randomized manner, perioperative complications and the visual results associated with continuation or interruption of oral anticoagulant therapy before pars plana vitrectomy (PPV) under retrobulbar anaesthesia. The main objective of this trial is to compare haemostasis-related perioperative complications of PPV in patients maintaining anticoagulant therapy before surgery compared to patients with an interruption in this therapy before surgery.

METHODS

Ninety-six patients will be randomly assigned to either the control group, in whom oral anticoagulant therapy will be interrupted and substituted with subcutaneous heparin according to local clinical practice, or the intervention group in whom oral anticoagulant therapy will not be interrupted before surgery. Patients will be stratified according to the oral anticoagulant they were taking (direct or indirect anticoagulation). They will be followed up for 12 weeks, and the primary outcome, and haemorrhagic complications until 15 days after surgery, will be evaluated.

DISCUSSION

This trial will provide novel information on the possibility of continuing anticoagulant therapy during PPV. The benefits expected from the change in the current surgical management paradigm for anticoagulated patients would be a decreased risk in the incidence of perioperative thromboembolic events and the possibility of performing surgery without delay and without the need for patients to change their usual anticoagulation protocol to the more complex and less safe substitutive therapy.

TRIAL REGISTRATION

Clinical Trials Register EudraCT, 2018-000753-45. Registered on 11 November 2018.

Postoperative Complications of Pars Plana Vitrectomy for Diabetic Retinal Disease

Despite recent advances in the medical management of diabetic retinal disease, there remain established indications for vitreoretinal surgery in the treatment of severe proliferative diabetic retinopathy. These include non-clearing vitreous hemorrhage and tractional retinal detachment. Advances in surgical instrumentation, technique, and experience have led to improved visual outcomes, as well as a corresponding decrease in the incidence of postoperative complications. However, the presence of systemic and ocular factors in diabetic patients increases the risk of adverse events compared to non-diabetic individuals. This review will focus on the most important postoperative complications following pars plana vitrectomy, with specific considerations for the diabetic patient.

Ophthalmic regional blocks: management, challenges, and solutions

In the past decade ophthalmic anesthesia has witnessed a major transformation. The sun has set on the landscape of ophthalmic procedures performed under general anesthesia at in-hospital settings. In its place a new dawn has ushered in the panorama of eye surgeries conducted under regional and topical anesthesia at specialty eye care centers. The impact of the burgeoning geriatric population is that an increasing number of elderly patients will present for eye surgery. In order to accommodate increased patient volumes and simultaneously satisfy administrative initiatives directed at economic frugality, administrators will seek assistance from anesthesia providers in adopting measures that enhance operating room efficiency. The performance of eye blocks in a holding suite meets many of these objectives. Unfortunately, most practicing anesthesiologists resist performing ophthalmic regional blocks because they lack formal training. In future, anesthesiologists will need to block eyes and manage common medical conditions because economic pressures will eliminate routine preoperative testing. This review addresses a variety of topical issues in ophthalmic anesthesia with special emphasis on cannula and needle-based blocks and the new-generation antithrombotic agents. In a constantly evolving arena, the sub-Tenon's block has gained popularity while the deep angulated intraconal (retrobulbar) block has been largely superseded by the shallower extraconal (peribulbar) approach. Improvements in surgical technique have also impacted anesthetic practice. For example, phacoemulsification techniques facilitate the conduct of cataract surgery under topical anesthesia, and suture-free vitrectomy ports may cause venous air embolism during air/fluid exchange. Hyaluronidase is a useful adjuvant because it promotes local anesthetic diffusion and hastens block onset time but it is allergenic. Ultrasound-guided eye blocks afford real-time visualization of needle position and local anesthetic spread. An advantage of sonic guidance is that it may eliminate the hazard of globe perforation by identifying abnormal anatomy, such as staphyloma.