Antiplatelets and anticoagulants in vitreoretinal surgery, with a special emphasis on novel anticoagulants: a national survey and review

Antiplatelets and Anticoagulants in Vitreoretinal Surgery: A Systematic Review

Background: Antiplatelets and anticoagulants have substantially influenced contemporary vitreoretinal surgical practices. The availability of new oral blood thinners has recently spurred a renewed interest in the clinical approach to vitreoretinal surgical conditions since it may be difficult for the surgeon to collect sufficient evidence-based data to decide whether to discontinue or continue such medications. Materials and Methods: We conducted a systematic review on the use of antiplatelets and/or anticoagulants in the perioperative setting in vitreoretinal surgery and their possible complications, following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The level of evidence, according to the Oxford Centre for Evidence-Based Medicine (OCEM) 2011 guidelines, and the quality of evidence, according to the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system, were assessed for all included articles. Results: In total, 2310 articles were initially extracted, out of which 1839 articles were obtained after duplicates were removed and their abstracts were screened. A total of 27 articles were included in the full-text review. Finally, a remaining 22 articles fulfilled the inclusion criteria. Conclusions: Even though there is just a small number of studies with solid results, the advantage of using antiplatelets and/or anticoagulants in vitreoretinal surgery seems to outweigh the disadvantages, which are mainly related to postoperative hemorrhagic complications.

Factors related to postoperative vitreous hemorrhage after small-gauge vitrectomy in proliferative diabetic retinopathy patients

BACKGROUND

The role of anticoagulation or antiplatelet on post-vitrectomy vitreous hemorrhage (POVH) in patients with proliferative diabetic retinopathy (PDR) is rarely investigated in the small-gauge vitrectomy era. We investigate the relationship between the long-term use of those medications and POVH in a group of PDR patients.

METHODS

A retrospective cohort study was carried out in a group of PDR patients who underwent small-gauge vitrectomy in our center. The baseline data on diabetes, diabetic complications, long-term use of anticoagulants and antiplatelet agents, ocular findings, and vitrectomy details were collected. The occurrence of POVH was recorded during at least three-month follow-up. Factors related to POVH were analyzed using logistic analysis.

RESULTS

During a median follow-up of 16 weeks, 5% (11/220) of patients had POVH, and 75 had received antiplatelet or anticoagulation agents before the operation. Factors related to persistent POVH were the use of antiplatelet or anticoagulation agents (5.98, 1.75-20.45, p = 0.004), the presence of myocardial revascularization (130.65, 3.53-4834.50, p = 0.008), the presence of coronary artery disease (CAD) treated with medicine (56.52, 1.99-1604.06, p = 0.018), and younger age (0.86, 0.77-0.96, p = 0.012). For those receiving preoperative antiplatelet or anticoagulation agents, the probability of developing POVH was higher in the patients whose previous therapy was adjusted compared to those with continued therapy (p = 0.02 by Log-rank test).

CONCLUSIONS

We identified long-term use of anticoagulation or antiplatelet medication, the presence of CAD, and younger age as three independent factors related to POVH. In PDR patients on long-term antiplatelet or anticoagulation medications, particular attention should be given to controlling intraoperative bleeding, and follow-up for POVH should be scheduled.

Risk Factors for Severe Bleeding Complications in Vitreoretinal Surgery and the Role of Antiplatelet or Anticoagulant Agents

PURPOSE

To evaluate the influences and risk factors for severe bleeding complications during vitreoretinal surgery and to investigate the role of antiplatelet and anticoagulant agents.

DESIGN

Prospective trial.

PARTICIPANTS

Patients undergoing vitreoretinal surgery.

METHODS

The procedures included were pars plana vitrectomy and scleral buckling. We developed a uniform classification to grade the bleeding severity. Bleeding was graded on an ordinal scale ranging from 0 to 5. Immediately after surgery and 1 day later, the incidence and the severity of bleeding events was documented on a standardized form. A grade of 3 or more was defined as severe bleeding. Furthermore, the influence of known systemic disorders before surgery, the type of anesthesia, type of surgical procedure, intraoperative blood pressure, and the use or change of antiplatelet or anticoagulant agents on intraoperative bleeding was analyzed.

MAIN OUTCOME MEASURES

Incidence and risk factors for severe intraoperative bleeding events.

RESULTS

Data from 374 eyes undergoing vitreoretinal procedures were included in our study (mean age, 67.6 ± 12.9 years). A severe intraoperative bleeding event was observed in 15 eyes (4%). We found that concomitant diseases such as diabetes mellitus and carotid artery stenosis, the presence of diabetic retinopathy, younger age, and scleral buckling combined with a transscleral puncture were associated significantly with severe bleeding events. By contrast, use of antiplatelet or anticoagulant agents, or both, had no significant influence on severe intraoperative bleeding events.

CONCLUSIONS

Although external manipulations during buckling surgery (e.g., drainage of subretinal fluid) and concomitant diseases such as diabetes mellitus and carotid artery stenosis influences the risk of severe intraoperative bleeding events, we did not detect an increased risk related to coexisting antiplatelet or anticoagulant medication use, or both.

[Anticoagulation and platelet aggregation inhibition : What needs to be considered in the ophthalmological practice]

Several eye diseases requiring surgical intervention occur predominantly in elderly. Therefore, there is a significant co-incidence with systemic co-morbidities, which often do require anti-coagulation. There are several approaches to influence hemostasis pharmacologically. The number of options has increased substantially due to introduction of new drugs. This article provides an overview on the option range and gives insight, why this is of importance from the perspective of internal medicine. In addition, the basic principles of adjusting the therapy is being reviewed. Furthermore, the pharmacological inhibition of hemostasis in the context of eye surgery is being discussed. Available literature is analyzed to understand the necessity to interrupt or change the anti-coagulation for eye surgery.

Limited Utility of Routine Tests Prior to Ophthalmologic Surgery: An Observational Study in a Japanese Hospital

Introduction:

Routine preoperative testing for low-risk surgeries without a clinical indication should be avoided; however, such tests are still frequently performed in Japan. This study was performed to assess the impact of routine preoperative tests in low-risk surgery in a Japanese medical setting.

Methods:

We performed a retrospective chart review to examine the utility of routine tests with respect to anesthetic management and postoperative complications in all patients aged ≥ 18 years whom ophthalmologists consulted with anesthesiologists before ophthalmologic surgery under general anesthesia.

Results:

During the 10-year study period, 1,234 anesthetic consultations and 1,211 routine preoperative tests (laboratory tests, chest X-rays, and electrocardiograms) were performed in Toyama University Hospital. In total, 59 patients (4.8% of the study population) canceled surgery after a battery of preoperative evaluation. Among them, 10 patients had incidental abnormalities that necessitated additional tests, and only three patients (0.2%) canceled surgery. In-hospital postoperative complications developed in nine patients (0.7%) whose routine test results made it difficult to predict development of these adverse events. No severe life-threatening events were noted in this survey.

Conclusions:

Routine tests prior to eye surgery for adults were of low value for perioperative management and prediction of development of in-hospital complications in this Japanese medical setting. Anesthesiologists and ophthalmologists should selectively order preoperative tests based on the medical interview and physical examination.

Comparative Incidence of Postoperative Hemorrhage in Vitreoretinal Surgery in Patients on Anti-Coagulants

BACKGROUND AND OBJECTIVE

Data regarding hemorrhagic complications of direct oral anticoagulants (DOACs) and vitreoretinal surgery are limited.

PATIENTS AND METHODS

Multicenter analysis of longitudinal, aggregated electronic health records of patients undergoing pars plana vitrectomy (PPV) with no prior history of ocular hemorrhage. Retrospective analysis of patients undergoing PPV between January 1, 2013, and December 31, 2019. The main outcomes were development of postoperative hemorrhagic complications within 1 month following vitreoretinal surgery.

RESULTS

A total of 58,131 eyes underwent PPV, with 2,956 (5.1%) on anticoagulant medication prior to surgery. Eight hundred twenty-eight eyes (1.4%) developed a postoperative hemorrhage. Of eyes with anticoagulation use, 50 of 2,956 (1.29%) developed a hemorrhage, whereas 778 of 55,175 (1.41%) of the eyes with no prior anticoagulation use developed a postoperative hemorrhage (P = .2107).

CONCLUSION

Use of DOACs prior to vitreoretinal surgery does not appear to be associated with increased rates of postoperative intraocular hemorrhage. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:374-379.].

Update on the perioperative management of antiplatelets and anticoagulants in ophthalmic surgery

INTRODUCTION

Anti-thrombotic drugs (antiplatelets and anticoagulants) are widely used for different clinical reasons. This means that there are an increasing number of patients undergoing elective ophthalmic surgery that are being treated with these drugs. A better knowledge of their implications and their peri-operative use may help to prevent surgical and secondary adverse events. There is often no firm recommendation on how to manage certain drugs in certain surgeries.

OBJECTIVE

To review the recommendations in the scientific literature as regards managing anti-thrombotic agents during the peri-operative period of ophthalmic surgery.

MATERIAL AND METHODS

A review was made of the relevant guidelines and studies using an antiplatelet and anticoagulant drugs approach for cataract, vitreo-retinal, glaucoma, oculoplastic, and strabismus surgeries.

RESULTS

Recommendations about whether to continue or discontinue anti-thrombotic drugs in the peri-operative period of different ophthalmic surgical fields are presented.

CONCLUSIONS

There are only firm recommendations of maintaining anti-thrombotic drugs as regards cataract surgery using phacoemulsification with topical anaesthesia. In other surgical fields, ophthalmologists should balance the risk of thromboembolic events and risks of haemorrhagic complications in order to carry out a proper management. A multi-disciplinary approach is recommended for complex cases. Additional studies should be performed to better characterise the peri-operative use of anti-thrombotic agents in order to prepare clinical guidelines for ophthalmic surgery.

Update on the perioperative management of antiplatelets and anticoagulants in ophthalmic surgery

INTRODUCTION

Anti-thrombotic drugs (antiplatelets and anticoagulants) are widely used for different clinical reasons. This means that there are an increasing number of patients undergoing elective ophthalmic surgery that are being treated with these drugs. A better knowledge of their implications and their peri-operative use may help to prevent surgical and secondary adverse events. There is often no firm recommendation on how to manage certain drugs in certain surgeries.

OBJECTIVE

To review the recommendations in the scientific literature as regards managing anti-thrombotic agents during the peri-operative period of ophthalmic surgery.

MATERIAL AND METHODS

A review was made of the relevant guidelines and studies using an antiplatelet and anticoagulant drugs approach for cataract, vitreo-retinal, glaucoma, oculoplastic, and strabismus surgeries.

RESULTS

Recommendations about whether to continue or discontinue anti-thrombotic drugs in the peri-operative period of different ophthalmic surgical fields are presented.

CONCLUSIONS

There are only firm recommendations of maintaining anti-thrombotic drugs as regards cataract surgery using phacoemulsification with topical anaesthesia. In other surgical fields, ophthalmologists should balance the risk of thromboembolic events and risks of haemorrhagic complications in order to carry out a proper management. A multi-disciplinary approach is recommended for complex cases. Additional studies should be performed to better characterise the peri-operative use of anti-thrombotic agents in order to prepare clinical guidelines for ophthalmic surgery.

Perioperative risk of bleeding with antithrombotic agents in macular surgery: a national, prospective, multicentre study

PURPOSE

To compare the risk of haemorrhagic complications in elective macular surgery between patients with no antithrombotic (AT) treatment (defined as patients with no history of AT therapy or who discontinued AT therapy) and patients who continued AT treatment during the surgery.

METHODS

E-case report forms were prospectively recorded in a database before vitreoretinal surgery and 1 month after. Data on patient characteristics, surgical techniques, haemorrhagic complications and antithrombotic status were collected. Patients with retinal detachment, proliferative diabetic retinopathy and previous retinal haemorrhage were excluded.

RESULTS

A total of 748 procedures (single procedure in one eye per patient) were performed between January and May 2019. Among them, 202 patients (27.0%) were treated with antithrombotic therapy at the time of surgery: 19.5% with antiplatelet agents (n = 146), 6.3% with anticoagulants (n = 47) including 3.2% (n = 24) patients treated with novel oral anticoagulants, 0.8% (n = 6) with anticoagulants and antiplatelet agents, and 0.4% (n = 3) with heparin. Overall, 92 patients (12.3%) developed one or more haemorrhagic complications, of which 63 (11.5%) and 29 (14.4%) were in the non-AT and AT group, respectively. The multivariate logistic regression model showed no difference between AT treatment groups regarding ocular bleeding complications (odds ratio [OR] 1.2, 95% confidence interval (CI) [0.7-2.2], p = 0.54).

CONCLUSION

No cases of uncontrolled or severe perioperative haemorrhage in patients continuing antithrombotic agents were reported in this selected population. For the majority of the patients taking antiplatelets or anticoagulants, these agents could be safely continued during macular surgery.

Effect of Anticoagulant Therapy on the Outcome of Descemet Membrane Endothelial Keratoplasty

PURPOSE

To analyze the effect of anticoagulant therapy (ACT) for systemic diseases on the outcome of Descemet membrane endothelial keratoplasty (DMEK).

METHODS

Consecutive eyes with Fuchs endothelial dystrophy that underwent DMEK between August 4, 2011, and July 15, 2016, were retrospectively analyzed. Data were obtained from the Cologne DMEK database at the University of Cologne, Germany. Best spectacle-corrected visual acuity (logMAR), endothelial cell density (at baseline and postoperatively up to 12 months), and rebubbling rates were compared between patients receiving ACT (ACT group) and those with no anticoagulant treatment (NCT group).

RESULTS

In this study, 329 eyes of 329 patients were included (ACT group n = 97, NCT group n = 232; mean age 69.9 ± 9.1 years). Bleeding was more common in the ACT group (P < 0.001). Preoperative best spectacle-corrected visual acuity was 0.59 ± 0.44 and 0.48 ± 0.35 logMAR for the ACT and NCT groups, respectively, which improved to 0.13 ± 0.08 and 0.08 ± 0.16 logMAR, respectively, at 12 months postoperatively. No significant difference in endothelial cell density loss at 12 months was found between the groups (ACT group 36.2% ± 14.7%, NCT group 38.5% ± 15.1%; P = 0.467). Rebubbling rate was 19.6% in the ACT group and 28.9% in the NCT group (P = 0.08).

CONCLUSIONS

Although ACT increases the risk for preoperative and intraoperative bleeding in DMEK, there seems to be no negative effect on DMEK outcome. Thus, it is not advisable to stop ACT for DMEK surgery.

Continuation of aspirin therapy before pars plana vitrectomy: Safe or not?

PURPOSE

To assess the safety of pars plana vitrectomy (PPV) in patients undergoing systemic treatment with aspirin.

METHODS

This prospective study enrolled consecutive patients undergoing PPV under percutaneous retrobulbar anesthesia between February 2016 and July 2018. Sixty-seven eyes from 67 patients on regular aspirin therapy were randomized into two groups: the continuation group (33 eyes), with aspirin continued during the perioperative period; and the discontinuation group (34 eyes), with aspirin discontinued for 3 to 7 days before surgery. Forty-three eyes from 43 patients who had no antiplatelet/anticoagulant therapy were used as a control group.

RESULTS

There was no significant difference in the incidence of hemorrhagic complications or the need for additional operations due to hemorrhagic complications among the three groups (p = 0.740 and p = 0.324, respectively). None of the patients in these three groups suffered from thromboembolic events during the follow-up period. Except for one case (3.0%) of lid ecchymosis in the continuation group, no eye experienced bleeding complications associated with the retrobulbar local anesthesia. In the continuation group, three eyes (9.1%) demonstrated postoperative hyphema that resolved spontaneously. In the discontinuation group, two eyes (5.9%) suffered from postoperative vitreous hemorrhage, of which one eye required secondary surgery and the other cleared spontaneously. One eye (2.9%) in the discontinuation group demonstrated postoperative hyphema that absorbed spontaneously. Three eyes (7.0%) in the control group experienced hyphema that absorbed spontaneously.

CONCLUSION

The outcomes of our study indicate that PPV under retrobulbar anesthesia can be safely performed without discontinuing systemic aspirin therapy.

Perioperative Management of Anticoagulants in Ocular Surgeries

Use of anticoagulant therapy has increased in patients presenting for ophthalmic surgery over the past decade. The decision of whether or not to discontinue anticoagulant medications prior to ophthalmic surgeries is nuanced and ultimately based on multiple factors including the type of surgery and the patient’s comorbidities and risk profile. In the setting of cataract surgery, no increased risk of bleeding with anticoagulation was observed in a large prospective study, which suggests that anticoagulation should not be interrupted for the average-risk patient on anticoagulation. In other types of ophthalmic surgery, expert opinion and studies are divided on the perioperative management of anticoagulant therapy. Preoperative thromboembolic risk stratification, intraoperative techniques to minimize bleeding, and postoperative management are also reviewed to generate more comprehensive recommendations on ophthalmic perioperative management of anticoagulation.

Safety of cataract surgery in patients treated with the new oral anticoagulants (NOACs)

PURPOSE

To evaluate the safety of phacoemulsification of cataract in patients taking new oral anticoagulants (NOACs).

METHODS

In a prospective case series, consecutive patients on NOACs (dabigatran, rivaroxaban, or apixaban) who were referred for uncomplicated cataract surgery to the eye institute underwent a thorough ophthalmological and hematological evaluation. Rivaroxaban and apixaban anti-factor Xa tests, and diluted thrombin time for dabigatran, were used for monitoring anticoagulation levels in blood. Blood was drawn for these tests just prior to surgery and at a peak level of the drug at about 4 h post-surgery (2 h after the drug was given). All surgeries were videotaped and patients were examined at 1 and 7 days after the operation. The main outcome measures included assessment of intra-operative, postoperative ocular bleeding, and other related complications.

RESULTS

Thirty-five eyes of 25 unrelated patients ranging in age from 63 to 92 years (mean 77.6 years) underwent phacoemulsification. Intra-operative bleeding was observed in 5 eyes from the conjunctiva or limbus at the main incision site. No intraocular bleeding occurred. No hemorrhagic complications were observed during the 1-week follow-up. According to anti-factor Xa levels prior to surgery and following surgery, 85% of the patients were on therapeutic levels of NOACs.

CONCLUSIONS

Clear corneal incision phacoemulsification performed under topical anesthesia can be safely performed in simple cases of cataract without discontinuing NOAC treatment.

[Management of anticoagulants in ophthalmic surgery-a survey among ophthalmic surgeons in Germany]

INTRODUCTION

As our population ages and comorbidities rise, ophthalmic surgeons are increasingly faced with patients on anticoagulant therapy or with clotting disorders. The ophthalmic surgeon has to weigh the perioperative risk of haemorrhage when anticoagulation continues against the risk of thromboembolism caused by discontinuation or changing the patient's medication (bridging, switching, cessation). There are currently no guidelines or recommendations.

METHODS

A survey was sent to the DOG (German Ophthalmologic Society) divisions and associated surgical organizations to determine the status quo. A questionnaire was sent out and filled out by the different groups of specialists.

RESULTS

All four divisions of the DOG and four associated organizations returned completed questionnaires. Surgical interventions were listed that are carried out during anticoagulant therapy without exceptions, as well as interventions that were classified to require medical adjustment. Although the assessments varied, general consensus was achieved regarding interventions not requiring adjustments due to anticoagulants (i. e., intravitreal injection, cataract surgery, laser and corneal operations, simple muscle surgery), and those interventions requiring adjustments in medications (glaucoma operations, complex retina surgery, eye socket surgery, complex surgery of the lid).

CONCLUSION

Main result of this survey was the specification of serious bleeding complications which are permanent vision loss and re-operation. They could serve as endpoint parameters for essential future investigations. Nevertheless, this survey makes clear that the decision about an adjustment of anticoagulant medication in ophthalmic surgery is currently made individually and not based on established standards.

Surgical management of diabetic tractional retinal detachments

Tractional retinal detachment is an end-stage form of diabetic retinopathy that occurs when contractile forces in the vitreous and neovascular tissue lead to the detachment of the neurosensory retina. We review the literature related to the management of this disease. Preoperative planning includes appropriate patient selection, diagnostic and prognostic imaging, and medical optimization with reduction of systemic risk factors. Use of antivascular endothelial growth factor for preoperative treatment has had significant benefits for tractional retinal detachment repair in improving surgical efficiency and outcomes. Advances in microsurgical instrumentation are discussed, with attention to small-gauge vitrectomy with improved flow dynamics, viewing strategies, and lighting allowing bimanual surgery. Special emphasis is placed on bimanual surgical technique, choice of tamponade, and the avoidance of iatrogenic damage. Complications and special considerations are further explored. Based on our compilation of relevant literature, we propose a surgical algorithm for the management of these complex patients.

Peri-operative management of ophthalmic patients on anti-thrombotic agents: a literature review

There is variability in the management of ophthalmic patients on anti-thrombotic agents (antiplatelets and anticoagulants) during the peri-operative period. A survey carried out in a UK teaching hospital on a cohort of ophthalmologists showed majority were comfortable with antiplatelet management but there was variability in managing patients on warfarin and direct oral anticoagulants (DOACs); 40% were unaware of existing guidelines. We aim to review the recommendations in the literature with regards to managing anti-thrombotic agents during the peri-operative period of ophthalmic surgery. We reviewed incidences of complications, specifically, the haemorrhagic complications associated. Pubmed search was carried out on relevant keywords from January 2007 to August 2017. All relevant UK guidelines including the Royal College of Ophthalmologists and British Society of Haematology were reviewed. Literature recommendations for routine cataract surgery under topical or sub-Tenon's anaesthesia would be to continue all anti-thrombotic agents. For sharp needle anaesthesia, avoidance of dual antiplatelet therapy was recommended and warfarin could be continued if INR within therapeutic range. Recommendations for surgeries in glaucoma, vitreo-retinal, oculoplastic and lacrimal; and strabismus are presented. No evidence was found for corneal surgery. Haemorrhagic complications are reported in all groups. Limitations of this review include the retrospective nature, lack of randomized control trials and the limited evidence regarding DOACs. It is important for ophthalmologists to be aware of and balance the risk of thromboembolic events and risks of haemorrhagic complications for ophthalmic surgery. A multi-disciplinary approach is recommended for complex cases.

Phacoemulsification cataract surgery in patients receiving novel oral anticoagulant medications

INTRODUCTION

An increasing number of patients are taking novel oral anticoagulant (NOAC) medication, making perioperative management in phacoemulsification surgery an important issue. This study reports the haemorrhagic complications of NOAC in phacoemulsification surgery.

DESIGN

Retrospective case study over a 4-year period.

METHODS

Consecutive cases receiving NOAC during the time of phacoemulsification were reviewed. Patients were either advised to continue medications (continued group) or withhold medications before surgery (withheld group).

MAIN OUTCOME MEASURES

Details including patient demographics, preoperative assessment, postoperative outcome and intraoperative, postoperative and systemic complications were recorded.

RESULTS

A total of 20,100 cases of phacoemulsification were performed. Of which, 66 cases were found to be on NOAC (0.33%). This included 66 eyes of 53 patients, with 42 continued and 24 withheld medications before surgery. There was no statistically significant difference between the two groups in demographics, cataract risk factors, baseline renal function, clotting profile, type of NOAC, incision size, phacoemulsification energy, preoperative and postoperative visual acuity. There was also no significant difference in intraoperative, postoperative and systemic complications (p = 1.00 and 0.53, Fischer's exact test). None of the patients in the continued group had postoperative complications; two cases in the withheld group receiving retrobulbar anaesthesia had bruising and subconjunctival haemorrhage after resumption of NOAC (p = 0.13, Fischer's exact test).

CONCLUSION

The present study found no difference in haemorrhagic complications between cases continuing and withholding NOAC during phacoemulsification. Nevertheless, the potential risks and benefits to continue or withhold NOAC perioperatively should be carefully considered via a multidisciplinary approach.