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Consultation section
Q: Attitudes regarding the concomitant use of anticoagulants with elective cataract surgery appear to be changing. While it is recognized that an increased risk of operative bleeding must be accepted by surgeon and patient if anticoagulants are continued through the perioperative period, there is also a real concern about systemic risks if anticoagulants are discontinued. What is your current approach to those patients needing elective cataract surgery who are maintained on warfarin sodium (Coumadin®) , aspirin, or dipyridamole (Persantine®)?
A:
consultation section Edited by Samuel Masket, M.D.
Patients taking anticoagulants pose a special challenge in planning cataract surgery because of their concurrent systemic diseases, the hemorrhagic risk, and, not uncommonly, complicating ocular disease. These patients can be considered in two categories: those on platelet inhibitors and those maintained on warfarin sodium (Coumadin®). There is a third group of patients who take heparin (heparin inhibits the external clotting system; warfarin compounds inhibit the intrinsic clotting system). However, these patients rarely present for cataract surgery since heparinization is usually short term and surgery can be deferred until the heparin is discontinued or replaced with warfarin compounds. Platelet inhibitors include aspirin, dipyridamole, and nonsteroidal anti-inflammatory drugs. Lactam antibiotics can also inhibit platelets when given in large concentrations, but this rarely poses a problem for patients having cataract surgery. Aspmn irreversibly acetylates and inactivates cyclooxygenase, which prevents platelet aggregation for the ten-day lifespan of the affected platelets. This effect can be achieved with as little as 80 to 100 mg of aspirin per day. In approximately one half of normal subjects, the bleeding time increases for four days after ingesting a single dose of aspirin. Nonsteroidal anti-inflammatory agents block cyclooxygenase reversibly and thus have minimal clinical effect on platelet function or bleeding time. Dipyridamole inhibits phosphodiesterase and may enhance the platelet-inactivating effects of aspirin. Platelet inhibitors are prescribed to reduce the risk of myocardial infarction, stroke, and embolic
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
531
phenomena elsewhere in the body. If these agents are discontinued for a short period of time, there may be a small risk of stroke, myocardial infarction, or other embolic complication. This would seem to be more likely in patients who have experienced symptoms related to these problems in the few weeks prior to cessation of medication. To compensate for the platelet inhibitory actions of aspirin, one must remember that 10% of platelets are replaced daily; therefore, in two days there are approximately 50,000 platelets/mm 3 , which is the number generally felt to be required to prevent spontaneous bleeding. The ophthalmic risks of maintaining patients on platelet inhibitors are unclear. The literature rarely discusses the risks of ocular complications of performing cataract surgery on patients taking platelet inhibitors. My current practice is to maintain patients on their platelet inhibitors if they have evidence of any form of severe systemic vascular disease. If aspirin has been prescribed or recommended simply as a prophylactic measure in the absence of previous symptomatology, then I generally ask patients to stop the aspirin for approximately seven days prior to surgery. This ensures that there are adequate platelets to provide good clotting function. With warfarin compounds, the situation is more complex, both because of the severity of systemic diseases for which they are used and the potential ocular complications of Coumadin anticoagulation. Warfarin compounds are generally prescribed to prevent embolic complications of artificial cardiac valves, intermittent atrial fibrillation, and deepvein thrombosis. They are also sometimes prescribed as a general prophylaxis against myocardial infarction and stroke. Withholding warfarin compounds poses a small but definite risk of emboli in patients with cardiac valves, intermittent atrial fibrillation, and recent pulmonary emboli. The risk of stroke in artificial valve patients may be in the range of 20% per year when patients are not anticoagulated; hence one week of cessation of anticoagulation may not pose a great systemic risk. When warfarin compounds are stopped, full reversal of their effect occurs in three to five days. Vitamin K or fresh frozen plasma can be administered to reverse the effect rapidly, but there is some evidence that this treatment leads to a hypercoagulable state. Several small prospective studies have evaluated the results of cataract surgery in patients on warfarin compounds. In all of these studies, hemorrhagic complications were minor, the worst being hyphema. No patient sustained expulsive supra532
choroidal hemorrhage. However, it is important to note that these studies involved a small patient population. Considering the generally low incidence of expulsive hemorrhage, a large group of patients would have to be studied to determine more accurately the incidence of hemorrhagic complications of intraocular surgery in patients receiving warfarin compounds. My practice for patients taking warfarin compounds is to discuss the medical implications of their cessation at length with the patient and the patient's internist. I now tend to leave patients on warfarin compounds if they are binocular and have few or no risk factors for expulsive hemorrhage (such as glaucoma or systemic hypertension). If the patient is one-eyed and has risk factors for expulsive hemorrhage, then I generally prefer to discontinue the warfarin compounds. They are generally resumed the afternoon of or the morning after surgery. When I perform surgery on patients taking warfarin compounds, certain precautions are indicated. For anesthesia, I use a peribulbar rather than a retrobulbar injection. If feasible, I do not use a bridle suture and prefer using a non-cutting needle. I perform phacoemulsification exclusively on these patients and use a sutureless wound configuration. A self-sealing incision provides some measure of protection against a complete expulsive hemorrhage. There are no clear-cut answers for the management of these patients; withholding or continuing anticoagulants in patients undergoing cataract surgery is accepted standard practice.. The internist and the patient should be heavily involved in the decision-making process. In particular, patients taking warfarin compounds are often knowledgeable about their condition and implications of continuing or discontinuing the medications. Teamwork and careful planning are essential in the management of these complex patients. Douglas D. Koch, M.D. Houston, Texas
A: Modern cataract surgery has become increasingly atraumatic and can be accomplished without complications in most patients receiving anticoagulant therapy. Ideally, an ophthalmologist would not operate on a patient with an extended bleeding time. However, some cataract patients have life-
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
threatening conditions that require anticoagulation and discontinuing therapy could place the patient at serious risk. The benefits of continuing therapy in the cataract patient outweigh the risks· of . . discontinuing it using modern surgical techniques. Several studies have looked at this issue. A 1985 survey of the American Intra-Ocular Implant Society members showed that 75% discontinued warfarin sodium prior to and following a cataract operation. 1 A number of serious life-threatening complications resulted, including two deaths from cerebrovascular accidents, two non-fatal cerebrovascular accidents, one transient ischemic attack, a cerebral embolism, a pulmonary embolism and a deep-vein thrombosis. One patient required coronary bypass revision. The ocular complications resulting from bleeding with warfarin sodium were much less serious. Only three patients had complications considered sight threatening-one retinal hemorrhage, one expulsive choroidal hemorrhage, and one vitreous hemorrhage. The Netherlands Intra Ocular Implant Society surveyed its membership and recommended continuation of anticoagulant therapy because of the risk of systemic complications associated with its discontinuance. 2 For more than ten years I have performed cataract surgery without discontinuing anticoagulation therapy. During this time, I prospectively studied two series, one with 28 anticoagulated eyes having extracapsular cataract extraction and another with 14 anticoagulated eyes having phacoemulsification. There were no sight-threatening complications in either series. Similar results have been reported by Hall and associates. 3 ,4 These series, supported by my experience of cataract extraction with IOL implantation in anticoagulated patients without serious complications, lead me to believe that the risk of serious lifethreatening complications from discontinuing anticoagulant therapy far outweighs the possibility of sight-threatening complications from continued anticoagulation. Lynn B. McMahan, M.D. Hattiesburg, Mississippi
REFERENCES 1. Stone LS, Kline OR Jr, Sklar C. Intraocular lenses and
anticoagulation and antiplatelet therapy. American Intra-Ocular Implant Soc J 1985; 11:165-168 2. Moll AC, Van-Rij G, Van der Loos TL. Anticoagulant therapy and cataract surgery. Doc Ophthalmol 72: 367-373 3. Hall DL, Steen WH Jr, Drummond JW. Anticoagulants
and cataract surgery. Ann Ophthalmol1980; 12:759760 4. Hall DL, Steen WH Jr, Drummond JW, Byrd WA. Anticoagulants and cataract surgery. Ophthalmic Surg 1988; 19:221-222
A: The use of anticoagulants in patients having cataract surgery is a challenge and requires cooperation between internists and cataract surgeons. Hemorrhagic ocular complications are more likely to occur if the anticoagulant is continued. Yet if the anticoagulant is discontinued long enough to allow normal coagulation to return (three to five days for Coumadin and 10 to 14 days for aspirin), the patient may have a higher risk of a thromboembolic event. I generally ask my patients to discontinue aspirin use ten days before surgery and have their internist adjust Coumadin levels to a low therapeutic range (1.3 to 1.5 times normal prothrombin). If the internist feels such action places the patient in significant jeopardy and the patient continues anticoagulant therapy, I discuss the risks and proceed with surgery. Several modifications can reduce the likelihood of intraocular hemorrhage. If possible, I do not use a bridle suture and use fine-point cautery whenever necessary. I place the wound away from the larger Axenfeld loops, away from the horizontal meridians, and more anterior than usual. In rare cases a clear corneal incision is the best alternative, although suture irritation and induced astigmatism are more likely. Epinephrine in the irrigation fluid can also be helpful. A self-sealing type of incision is extremely advantageous. Its construction mandates entrance into the anterior chamber in clear cornea, anterior to the angle vessels that are often the source of persistent bleeding and postoperative hyphema. Although there have been several reports of an increased incidence of hyphema with this type of incision, I have not observed a single case since I began using this incision almost two years ago. At the end of surgery I prefer to "firm" the globe to a high normal intraocular pressure (lOP) by infusing balanced salt solution (BSS) through a side-port incision. This helps prevent inflow of wound blood, making postoperative hyphema less likely. Additionally, by injecting air, viscoelastic, or BSS through the side-port incision, one can more easily tampanode an intraocular hemorrhage if a selfsealing wound is made.
J CATARACf REFRACf SURG-VOL 18, SEPTEMBER 1992
533
Finally, the issue of retrobulbar hemorrhage must be addressed. If it occurs in an anticoagulated patient, it may be more difficult to control. In case of a retrobulbar hemorrhage I place direct pressure on the globe for ten minutes and then evaluate the globe and orbit. 1 If the globe is soft and easily retropulsed and the lids are mobile, I proceed with small incision phacoemulsification. The use of peribulbar anesthesia may decrease the likelihood of retrobulbar hemorrhage. I have seen three cases of significant retrobulbar hemorrhage after peribulbar steroid injection with a short 5fs-inch needle so the possibility of this complication still exists. Fortunately, anticoagulated patients usually attain excellent surgical results regardless of the anesthetic technique selected by the surgeon; careful attention to the operative technique increases the chances of a successful outcome. Robert
J. Cionni, M.D.
Cincinnati, Ohio REFERENCE l. Cionni RJ, Osher RH. Retrobulbar hemorrhage. Ophthalmology 1991; 98:1153-1155
A: My current approach to cataract surgery for patients on anticoagulants is to maintain these medications throughout the perioperative period, including the day of surgery. Before adopting this policy, several of my patients had serious medical complications, including cardiovascular accidents and peripheral vascular clotting. l I take special precautions with anticoagulated patients. A red sticker is placed on the patient's admission record to remind me before starting the case that the patient is anticoagulated. For ECCE, no conjunctival dissection is performed. The limbus is cauterized and a clear corneal section is performed with an unguarded diamond knife. A single-plane vertical incision is created. No peripheral iridectomy is made. For phacoemulsification, the conjunctiva is cauterized at its limbal insertion prior to conjunctival dissection. Tenon's capsule is not dissected. The grooved incision is made 2 mm posterior to the limbus rather than the normal 3 mm, and the guarded diamond knife used to make the initial incision for the scleral tunnel is 534
preset to 0.35 mm rather than the usual 0.40 mm. This is to further protect against cutting deep scleral vessels. Otherwise a self-sealing 5.1-mmwidth incision is made. No special precautions are made for the retrobulbar injection. Though I accept that potentially there is an increased risk of operative bleeding, since adopting this technique I have had no postoperative hyphemas in over 100 anticoagulated patients. Calvin W. Roberts, M.D. New York, New York REFERENCE l. Roberts CW, Woods SM, Turner LS. Cataract surgery in anticoagulated patients. J Cataract Refract Surg
1991; 17:309-312
A: There are divergent opinions on this issue, both in the ophthalmic literature and among practicing ophthalmologists. Early studies on the subject, when ECCE was the predominant technique, did reflect an increased incidence of intraoperative and retrobulbar hemorrhage in anticoagulated patients. Thus, many physicians are unaware that current small inclSlon cataract surgery, with peribulbar anesthetic blocks and preoperative pressure lowering devices, carries only a minimal risk of intraocular or retrobulbar hemorrhage. I generally continue Coumadin, aspirin, or dipyridamole (Persantine®) during the entire perioperative period. I pay extra attention to aspects of the surgery where bleeding could occur, such as during the peribulbar and facial nerve block, and I apply extra cautery to the internal portion of the scleral pocket to minimize the risk of postoperative hyphema. In cases requiring pupilloplasty, combined procedures, or high risk cases (e.g., an obese, monocular patient with a history of glaucoma and hypertension), I prefer that Coumadin be withheld four to five days prior to surgery to allow the prothrombin level to return to control or near-control levels. The internist and I weigh the variable ocular and systemic risk factors and jointly decide on what course of action to recommend to the patient. If the patient is taking aspirin or Persantine with Coumadin as part of a combination anticoagulation therapy, I discontinue the aspirin or Persantine ten days prior to surgery only if I withhold the Coumadin. With patients taking aspirin or Persantine without concomitant Coumadin therapy, I gener-
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER
1992
ally continue those medications during the perioperative period irrespective of the specific ocular or systemic status. Lawrence Stone, M.D. Chicago, Illinois
A: No definitive article has yet been published on this issue. The available literature suggests that although bleeding problems (especially hyphemas) are more common if anticoagulants are continued, the visual outcome is not adversely affected. 1-3 Conversely, thrombotic episodes have been reported in patients in whom anticoagulants were discontinued. My current approach is to continue aspirin or dipyridamole therapy. If a patient is on warfarin sodium therapy for a limited time, as with certain angioplasty procedures, I postpone surgery until the warfarin is discontinued. If the patient is on long-term therapy, as with atrial fibrillation, mechanical prosthetic heart valves, or severe atherosclerotic disease, I continue anticoagulant therapy, I prefer the prothrombin time to be in the low therapeutic range (approximately 18 in most laboratories). I use cautery more judiciously and make the incision more anteriorly. Specifically, I do not use a scleral flap incision in these patients. Although astigmatism may be increased slightly, I feel this minimizes the risk of perioperative hemorrhage. The remainder of the surgical procedure is unchanged from standard practice.
sician to determine if the medication can be discontinued. If so, I ask the patient to stop the medication two days before surgery and restart it two days after surgery. If the medication cannot be discontinued, I alter the surgical procedure by reducing the length of the tunnel incision and enter the chamber more anteriorly. Meticulous cauterization will control any bleeding as it is encountered and generally prevent problems from developing. Bernard A. Milstein, M.D. Galveston, Texas
A:
A:
For patients who have valve implants or dialysis with administration of anticoagulants, I would continue the use of anticoagulants to protect against possible systemic risk, despite the increased risk of operative bleeding. Occasionally a patient's physician advises that anticoagulants be discontinued one week preoperatively, but if the physician finds it risky, I perform surgery in a manner that minimizes bleeding. To eliminate bleeding caused by a retrobulbar injection, I would only use a few drops of 1 0% cocaine preoperatively for anesthesia. With a diamond knife I would make a corneal incision where the limbal vessels end, thereby minimizing bleeding. For patients implanted with a pacemaker on anticoagulant therapy, a corneal incision is strongly recommended because bipolar cautery may be dangerous. When retrobulbar anesthesia is eliminated, a smaller incision is preferred. I make a 4 mm incision, perform phacoemulsification, and insert a silicone IOL through an injector. While phacoemulsification is performed, damage to the iris should be avoided and the iridectomy eliminated. If necessary, I would use an argon laser to perform iridectomy postoperatively. Although it is well known that Asians tend to produce more fibrin than Caucasians, I have never observed any fibrin reaction in my patients on anticoagulants. It is also my impression that postoperative inflammation and posterior synechias rarely occur. The combined technique of corneal incision, instillation of anesthesia, and implantation of a silicone IOL is my routine today. This technique is less likely to produce against-the-rule astigmatism and postoperative inflammation. Additionally, this particular intraocular technique is easy to perform.
When I see a patient who is on anticoagulants and needs cataract surgery, I first contact his/her phy-
Tokyo,]apan
Steven P. Gainey, M.D. Manitowoc, Wisconsin
REFERENCES 1. Gainey SP, Robertson DM, Fay W, Ilstrup D. Ocular surgery on patients receiving long-term warfarin therapy. Am J Ophth 1989; 108:142-146 2. Stone LS, Kline OR Jr, Sklar C. Intraocular lenses and anticoagulation and antiplatelet therapy. Am Intra-Ocular Implant Soc J 1985; 11:165-168 3. McMahan LB. Anticoagulants and cataract surgery. J Cataract Refract Surg 1988; 14:569-571
Kimiya Shimizu, M.D.
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
535
A:
consultation section Edited by Samuel Masket, M.D.
Patients taking anticoagulants pose a special challenge in planning cataract surgery because of their concurrent systemic diseases, the hemorrhagic risk, and, not uncommonly, complicating ocular disease. These patients can be considered in two categories: those on platelet inhibitors and those maintained on warfarin sodium (Coumadin®). There is a third group of patients who take heparin (heparin inhibits the external clotting system; warfarin compounds inhibit the intrinsic clotting system). However, these patients rarely present for cataract surgery since heparinization is usually short term and surgery can be deferred until the heparin is discontinued or replaced with warfarin compounds. Platelet inhibitors include aspirin, dipyridamole, and nonsteroidal anti-inflammatory drugs. Lactam antibiotics can also inhibit platelets when given in large concentrations, but this rarely poses a problem for patients having cataract surgery. Aspmn irreversibly acetylates and inactivates cyclooxygenase, which prevents platelet aggregation for the ten-day lifespan of the affected platelets. This effect can be achieved with as little as 80 to 100 mg of aspirin per day. In approximately one half of normal subjects, the bleeding time increases for four days after ingesting a single dose of aspirin. Nonsteroidal anti-inflammatory agents block cyclooxygenase reversibly and thus have minimal clinical effect on platelet function or bleeding time. Dipyridamole inhibits phosphodiesterase and may enhance the platelet-inactivating effects of aspirin. Platelet inhibitors are prescribed to reduce the risk of myocardial infarction, stroke, and embolic
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
531
phenomena elsewhere in the body. If these agents are discontinued for a short period of time, there may be a small risk of stroke, myocardial infarction, or other embolic complication. This would seem to be more likely in patients who have experienced symptoms related to these problems in the few weeks prior to cessation of medication. To compensate for the platelet inhibitory actions of aspirin, one must remember that 10% of platelets are replaced daily; therefore, in two days there are approximately 50,000 platelets/mm 3 , which is the number generally felt to be required to prevent spontaneous bleeding. The ophthalmic risks of maintaining patients on platelet inhibitors are unclear. The literature rarely discusses the risks of ocular complications of performing cataract surgery on patients taking platelet inhibitors. My current practice is to maintain patients on their platelet inhibitors if they have evidence of any form of severe systemic vascular disease. If aspirin has been prescribed or recommended simply as a prophylactic measure in the absence of previous symptomatology, then I generally ask patients to stop the aspirin for approximately seven days prior to surgery. This ensures that there are adequate platelets to provide good clotting function. With warfarin compounds, the situation is more complex, both because of the severity of systemic diseases for which they are used and the potential ocular complications of Coumadin anticoagulation. Warfarin compounds are generally prescribed to prevent embolic complications of artificial cardiac valves, intermittent atrial fibrillation, and deepvein thrombosis. They are also sometimes prescribed as a general prophylaxis against myocardial infarction and stroke. Withholding warfarin compounds poses a small but definite risk of emboli in patients with cardiac valves, intermittent atrial fibrillation, and recent pulmonary emboli. The risk of stroke in artificial valve patients may be in the range of 20% per year when patients are not anticoagulated; hence one week of cessation of anticoagulation may not pose a great systemic risk. When warfarin compounds are stopped, full reversal of their effect occurs in three to five days. Vitamin K or fresh frozen plasma can be administered to reverse the effect rapidly, but there is some evidence that this treatment leads to a hypercoagulable state. Several small prospective studies have evaluated the results of cataract surgery in patients on warfarin compounds. In all of these studies, hemorrhagic complications were minor, the worst being hyphema. No patient sustained expulsive supra532
choroidal hemorrhage. However, it is important to note that these studies involved a small patient population. Considering the generally low incidence of expulsive hemorrhage, a large group of patients would have to be studied to determine more accurately the incidence of hemorrhagic complications of intraocular surgery in patients receiving warfarin compounds. My practice for patients taking warfarin compounds is to discuss the medical implications of their cessation at length with the patient and the patient's internist. I now tend to leave patients on warfarin compounds if they are binocular and have few or no risk factors for expulsive hemorrhage (such as glaucoma or systemic hypertension). If the patient is one-eyed and has risk factors for expulsive hemorrhage, then I generally prefer to discontinue the warfarin compounds. They are generally resumed the afternoon of or the morning after surgery. When I perform surgery on patients taking warfarin compounds, certain precautions are indicated. For anesthesia, I use a peribulbar rather than a retrobulbar injection. If feasible, I do not use a bridle suture and prefer using a non-cutting needle. I perform phacoemulsification exclusively on these patients and use a sutureless wound configuration. A self-sealing incision provides some measure of protection against a complete expulsive hemorrhage. There are no clear-cut answers for the management of these patients; withholding or continuing anticoagulants in patients undergoing cataract surgery is accepted standard practice.. The internist and the patient should be heavily involved in the decision-making process. In particular, patients taking warfarin compounds are often knowledgeable about their condition and implications of continuing or discontinuing the medications. Teamwork and careful planning are essential in the management of these complex patients. Douglas D. Koch, M.D. Houston, Texas
A: Modern cataract surgery has become increasingly atraumatic and can be accomplished without complications in most patients receiving anticoagulant therapy. Ideally, an ophthalmologist would not operate on a patient with an extended bleeding time. However, some cataract patients have life-
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
threatening conditions that require anticoagulation and discontinuing therapy could place the patient at serious risk. The benefits of continuing therapy in the cataract patient outweigh the risks· of . . discontinuing it using modern surgical techniques. Several studies have looked at this issue. A 1985 survey of the American Intra-Ocular Implant Society members showed that 75% discontinued warfarin sodium prior to and following a cataract operation. 1 A number of serious life-threatening complications resulted, including two deaths from cerebrovascular accidents, two non-fatal cerebrovascular accidents, one transient ischemic attack, a cerebral embolism, a pulmonary embolism and a deep-vein thrombosis. One patient required coronary bypass revision. The ocular complications resulting from bleeding with warfarin sodium were much less serious. Only three patients had complications considered sight threatening-one retinal hemorrhage, one expulsive choroidal hemorrhage, and one vitreous hemorrhage. The Netherlands Intra Ocular Implant Society surveyed its membership and recommended continuation of anticoagulant therapy because of the risk of systemic complications associated with its discontinuance. 2 For more than ten years I have performed cataract surgery without discontinuing anticoagulation therapy. During this time, I prospectively studied two series, one with 28 anticoagulated eyes having extracapsular cataract extraction and another with 14 anticoagulated eyes having phacoemulsification. There were no sight-threatening complications in either series. Similar results have been reported by Hall and associates. 3 ,4 These series, supported by my experience of cataract extraction with IOL implantation in anticoagulated patients without serious complications, lead me to believe that the risk of serious lifethreatening complications from discontinuing anticoagulant therapy far outweighs the possibility of sight-threatening complications from continued anticoagulation. Lynn B. McMahan, M.D. Hattiesburg, Mississippi
REFERENCES 1. Stone LS, Kline OR Jr, Sklar C. Intraocular lenses and
anticoagulation and antiplatelet therapy. American Intra-Ocular Implant Soc J 1985; 11:165-168 2. Moll AC, Van-Rij G, Van der Loos TL. Anticoagulant therapy and cataract surgery. Doc Ophthalmol 72: 367-373 3. Hall DL, Steen WH Jr, Drummond JW. Anticoagulants
and cataract surgery. Ann Ophthalmol1980; 12:759760 4. Hall DL, Steen WH Jr, Drummond JW, Byrd WA. Anticoagulants and cataract surgery. Ophthalmic Surg 1988; 19:221-222
A: The use of anticoagulants in patients having cataract surgery is a challenge and requires cooperation between internists and cataract surgeons. Hemorrhagic ocular complications are more likely to occur if the anticoagulant is continued. Yet if the anticoagulant is discontinued long enough to allow normal coagulation to return (three to five days for Coumadin and 10 to 14 days for aspirin), the patient may have a higher risk of a thromboembolic event. I generally ask my patients to discontinue aspirin use ten days before surgery and have their internist adjust Coumadin levels to a low therapeutic range (1.3 to 1.5 times normal prothrombin). If the internist feels such action places the patient in significant jeopardy and the patient continues anticoagulant therapy, I discuss the risks and proceed with surgery. Several modifications can reduce the likelihood of intraocular hemorrhage. If possible, I do not use a bridle suture and use fine-point cautery whenever necessary. I place the wound away from the larger Axenfeld loops, away from the horizontal meridians, and more anterior than usual. In rare cases a clear corneal incision is the best alternative, although suture irritation and induced astigmatism are more likely. Epinephrine in the irrigation fluid can also be helpful. A self-sealing type of incision is extremely advantageous. Its construction mandates entrance into the anterior chamber in clear cornea, anterior to the angle vessels that are often the source of persistent bleeding and postoperative hyphema. Although there have been several reports of an increased incidence of hyphema with this type of incision, I have not observed a single case since I began using this incision almost two years ago. At the end of surgery I prefer to "firm" the globe to a high normal intraocular pressure (lOP) by infusing balanced salt solution (BSS) through a side-port incision. This helps prevent inflow of wound blood, making postoperative hyphema less likely. Additionally, by injecting air, viscoelastic, or BSS through the side-port incision, one can more easily tampanode an intraocular hemorrhage if a selfsealing wound is made.
J CATARACf REFRACf SURG-VOL 18, SEPTEMBER 1992
533
Finally, the issue of retrobulbar hemorrhage must be addressed. If it occurs in an anticoagulated patient, it may be more difficult to control. In case of a retrobulbar hemorrhage I place direct pressure on the globe for ten minutes and then evaluate the globe and orbit. 1 If the globe is soft and easily retropulsed and the lids are mobile, I proceed with small incision phacoemulsification. The use of peribulbar anesthesia may decrease the likelihood of retrobulbar hemorrhage. I have seen three cases of significant retrobulbar hemorrhage after peribulbar steroid injection with a short 5fs-inch needle so the possibility of this complication still exists. Fortunately, anticoagulated patients usually attain excellent surgical results regardless of the anesthetic technique selected by the surgeon; careful attention to the operative technique increases the chances of a successful outcome. Robert
J. Cionni, M.D.
Cincinnati, Ohio REFERENCE l. Cionni RJ, Osher RH. Retrobulbar hemorrhage. Ophthalmology 1991; 98:1153-1155
A: My current approach to cataract surgery for patients on anticoagulants is to maintain these medications throughout the perioperative period, including the day of surgery. Before adopting this policy, several of my patients had serious medical complications, including cardiovascular accidents and peripheral vascular clotting. l I take special precautions with anticoagulated patients. A red sticker is placed on the patient's admission record to remind me before starting the case that the patient is anticoagulated. For ECCE, no conjunctival dissection is performed. The limbus is cauterized and a clear corneal section is performed with an unguarded diamond knife. A single-plane vertical incision is created. No peripheral iridectomy is made. For phacoemulsification, the conjunctiva is cauterized at its limbal insertion prior to conjunctival dissection. Tenon's capsule is not dissected. The grooved incision is made 2 mm posterior to the limbus rather than the normal 3 mm, and the guarded diamond knife used to make the initial incision for the scleral tunnel is 534
preset to 0.35 mm rather than the usual 0.40 mm. This is to further protect against cutting deep scleral vessels. Otherwise a self-sealing 5.1-mmwidth incision is made. No special precautions are made for the retrobulbar injection. Though I accept that potentially there is an increased risk of operative bleeding, since adopting this technique I have had no postoperative hyphemas in over 100 anticoagulated patients. Calvin W. Roberts, M.D. New York, New York REFERENCE l. Roberts CW, Woods SM, Turner LS. Cataract surgery in anticoagulated patients. J Cataract Refract Surg
1991; 17:309-312
A: There are divergent opinions on this issue, both in the ophthalmic literature and among practicing ophthalmologists. Early studies on the subject, when ECCE was the predominant technique, did reflect an increased incidence of intraoperative and retrobulbar hemorrhage in anticoagulated patients. Thus, many physicians are unaware that current small inclSlon cataract surgery, with peribulbar anesthetic blocks and preoperative pressure lowering devices, carries only a minimal risk of intraocular or retrobulbar hemorrhage. I generally continue Coumadin, aspirin, or dipyridamole (Persantine®) during the entire perioperative period. I pay extra attention to aspects of the surgery where bleeding could occur, such as during the peribulbar and facial nerve block, and I apply extra cautery to the internal portion of the scleral pocket to minimize the risk of postoperative hyphema. In cases requiring pupilloplasty, combined procedures, or high risk cases (e.g., an obese, monocular patient with a history of glaucoma and hypertension), I prefer that Coumadin be withheld four to five days prior to surgery to allow the prothrombin level to return to control or near-control levels. The internist and I weigh the variable ocular and systemic risk factors and jointly decide on what course of action to recommend to the patient. If the patient is taking aspirin or Persantine with Coumadin as part of a combination anticoagulation therapy, I discontinue the aspirin or Persantine ten days prior to surgery only if I withhold the Coumadin. With patients taking aspirin or Persantine without concomitant Coumadin therapy, I gener-
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER
1992
ally continue those medications during the perioperative period irrespective of the specific ocular or systemic status. Lawrence Stone, M.D. Chicago, Illinois
A: No definitive article has yet been published on this issue. The available literature suggests that although bleeding problems (especially hyphemas) are more common if anticoagulants are continued, the visual outcome is not adversely affected. 1-3 Conversely, thrombotic episodes have been reported in patients in whom anticoagulants were discontinued. My current approach is to continue aspirin or dipyridamole therapy. If a patient is on warfarin sodium therapy for a limited time, as with certain angioplasty procedures, I postpone surgery until the warfarin is discontinued. If the patient is on long-term therapy, as with atrial fibrillation, mechanical prosthetic heart valves, or severe atherosclerotic disease, I continue anticoagulant therapy, I prefer the prothrombin time to be in the low therapeutic range (approximately 18 in most laboratories). I use cautery more judiciously and make the incision more anteriorly. Specifically, I do not use a scleral flap incision in these patients. Although astigmatism may be increased slightly, I feel this minimizes the risk of perioperative hemorrhage. The remainder of the surgical procedure is unchanged from standard practice.
sician to determine if the medication can be discontinued. If so, I ask the patient to stop the medication two days before surgery and restart it two days after surgery. If the medication cannot be discontinued, I alter the surgical procedure by reducing the length of the tunnel incision and enter the chamber more anteriorly. Meticulous cauterization will control any bleeding as it is encountered and generally prevent problems from developing. Bernard A. Milstein, M.D. Galveston, Texas
A:
A:
For patients who have valve implants or dialysis with administration of anticoagulants, I would continue the use of anticoagulants to protect against possible systemic risk, despite the increased risk of operative bleeding. Occasionally a patient's physician advises that anticoagulants be discontinued one week preoperatively, but if the physician finds it risky, I perform surgery in a manner that minimizes bleeding. To eliminate bleeding caused by a retrobulbar injection, I would only use a few drops of 1 0% cocaine preoperatively for anesthesia. With a diamond knife I would make a corneal incision where the limbal vessels end, thereby minimizing bleeding. For patients implanted with a pacemaker on anticoagulant therapy, a corneal incision is strongly recommended because bipolar cautery may be dangerous. When retrobulbar anesthesia is eliminated, a smaller incision is preferred. I make a 4 mm incision, perform phacoemulsification, and insert a silicone IOL through an injector. While phacoemulsification is performed, damage to the iris should be avoided and the iridectomy eliminated. If necessary, I would use an argon laser to perform iridectomy postoperatively. Although it is well known that Asians tend to produce more fibrin than Caucasians, I have never observed any fibrin reaction in my patients on anticoagulants. It is also my impression that postoperative inflammation and posterior synechias rarely occur. The combined technique of corneal incision, instillation of anesthesia, and implantation of a silicone IOL is my routine today. This technique is less likely to produce against-the-rule astigmatism and postoperative inflammation. Additionally, this particular intraocular technique is easy to perform.
When I see a patient who is on anticoagulants and needs cataract surgery, I first contact his/her phy-
Tokyo,]apan
Steven P. Gainey, M.D. Manitowoc, Wisconsin
REFERENCES 1. Gainey SP, Robertson DM, Fay W, Ilstrup D. Ocular surgery on patients receiving long-term warfarin therapy. Am J Ophth 1989; 108:142-146 2. Stone LS, Kline OR Jr, Sklar C. Intraocular lenses and anticoagulation and antiplatelet therapy. Am Intra-Ocular Implant Soc J 1985; 11:165-168 3. McMahan LB. Anticoagulants and cataract surgery. J Cataract Refract Surg 1988; 14:569-571
Kimiya Shimizu, M.D.
J CATARACT REFRACT SURG-VOL 18, SEPTEMBER 1992
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