Anticoagulants and anti platelet agents in oculoplastic surgery Esparaz and Sobel
KEY POINTS The oculoplastic surgeon must balance the risk of potential bleeding and subsequent sight-threatening complications against the risk of systemic ischemic and embolic events. Over the last few years, novel oral anticoagulants have emerged with shorter half-life than warfarin precluding the need to bridge; however, there are no standardized laboratory testing to monitor their anticoagulation effect. From a surgical standpoint it is recommended to continue oral anticoagulation rather than bridge therapy, because there is a significant morbidity associated with major bleeding perioperatively with heparin and lovenox.
for primary prevention, antiplatelet therapy is typically stopped 7–10 days prior to noncardiac, ambulatory surgery [9]. In contrast, patients who have had an ACS and especially in those who have coronary stent placement, the risk of discontinuing antiplatelet agents is much higher. Based on class I, level A evidence, American Heart Association states that patients who have coronary artery disease should continue aspirin therapy indefinitely [3]. According to the 2014 American College of Cardiology Guidelines, patients with bare-metal stents must have 6 weeks of uninterrupted dual antiplatelet therapy (DAPT) and those with drug-eluting stents require at least 6 months but preferably 12 months of the DAPT [2 ]. If surgery cannot be postponed, the recommendation is to continue DAPT in the perioperative period. The risk of stent thrombosis is highest in the first 4–6 weeks after implantation [10,11]. The risk after the initial period for drug-eluting stents continues and may stabilize by 6 months [12]. Warfarin is the mainstay therapy to prevent thromboembolic events, such as stroke, in patients with atrial fibrillation and in those with mechanical heart valves. It is also indicated for the treatment of deep venous thrombosis (DVT) and pulmonary embolism. Warfarin works by inhibiting vitamin K-dependent clotting factors produced in the liver. Its anticoagulant efficacy is measured by the internationalized normalized ratio. New oral anticoagulants (NOACs), such as dabigatran (FDA approved in 2010), which is a direct thrombin inhibitor, rivaroxaban (FDA approved in 2011), and apixaban (FDA approved in 2014), which are both factor Xa inhibitors, have been approved for long-term anticoagulation for atrial fibrillation. Dabigatran and rivaroxaban are also approved for the treatment of DVT and pulmonary embolism. &
Severe bleeding during oculoplastic surgery is rare (0.05–0.6%) and is often not correlated with whether or not a patient is on a blood thinner. Still, oculoplastic surgeons prefer to stop anticoagulants and antiplatelet agents, in coordination with cardiologists or neurologists, in the setting of certain procedures such as orbit surgery and blepharoplasty.
indicated for secondary prevention of coronary artery disease in those who have suffered an acute coronary syndrome (ACS) or undergone coronary stent placement (Table 1). Aspirin is also indicated for the primary prevention of acute MI in men over 45 years of age, and primary prevention of stroke in females over 55 years of age [7]. It is also indicated for the primary prevention of heart disease in diabetics over the age of 40 [7]. Antiplatelet agents irreversibly inhibit platelet function for 10 days, the lifespan of a platelet [8]. For patients taking antiplatelet medications
Table 1. Comparison of antiplatelet and anticoagulant agent properties Antiplatelets [4] Mechanism of action
Half-life
Platelet function recovery time
Aspirin
COX-1 inhibition
15–20 min
30% at 48 h
Clopidogrel
P2Y12 receptor inhibition
7–9 h
40% at 72 h
Prasugrel
P2Y12 receptor inhibition
7h
48–72 h
Ticagrelor
P2Y12 receptor inhibition
7–9 h
57% at 24 h
Anticoagulants [5,6] Mechanism of action
Half-life
Time to peak effect
Warfarin
Vitamin K antagonist
20–60 h
72–96 h
Dabigatran
Thrombin inhibitor
12–17 h
2–3 h
Rivaroxaban
Factor Xa inhibitor
9–13 h
0.5–3 h
Apixaban
Factor Xa inhibitor
9–14 h
3h
COX 1, cyclooxygenase 1.
1040-8738 Copyright
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
KEY POINTS The oculoplastic surgeon must balance the risk of potential bleeding and subsequent sight-threatening complications against the risk of systemic ischemic and embolic events. Over the last few years, novel oral anticoagulants have emerged with shorter half-life than warfarin precluding the need to bridge; however, there are no standardized laboratory testing to monitor their anticoagulation effect. From a surgical standpoint it is recommended to continue oral anticoagulation rather than bridge therapy, because there is a significant morbidity associated with major bleeding perioperatively with heparin and lovenox.
for primary prevention, antiplatelet therapy is typically stopped 7–10 days prior to noncardiac, ambulatory surgery [9]. In contrast, patients who have had an ACS and especially in those who have coronary stent placement, the risk of discontinuing antiplatelet agents is much higher. Based on class I, level A evidence, American Heart Association states that patients who have coronary artery disease should continue aspirin therapy indefinitely [3]. According to the 2014 American College of Cardiology Guidelines, patients with bare-metal stents must have 6 weeks of uninterrupted dual antiplatelet therapy (DAPT) and those with drug-eluting stents require at least 6 months but preferably 12 months of the DAPT [2 ]. If surgery cannot be postponed, the recommendation is to continue DAPT in the perioperative period. The risk of stent thrombosis is highest in the first 4–6 weeks after implantation [10,11]. The risk after the initial period for drug-eluting stents continues and may stabilize by 6 months [12]. Warfarin is the mainstay therapy to prevent thromboembolic events, such as stroke, in patients with atrial fibrillation and in those with mechanical heart valves. It is also indicated for the treatment of deep venous thrombosis (DVT) and pulmonary embolism. Warfarin works by inhibiting vitamin K-dependent clotting factors produced in the liver. Its anticoagulant efficacy is measured by the internationalized normalized ratio. New oral anticoagulants (NOACs), such as dabigatran (FDA approved in 2010), which is a direct thrombin inhibitor, rivaroxaban (FDA approved in 2011), and apixaban (FDA approved in 2014), which are both factor Xa inhibitors, have been approved for long-term anticoagulation for atrial fibrillation. Dabigatran and rivaroxaban are also approved for the treatment of DVT and pulmonary embolism. &
Severe bleeding during oculoplastic surgery is rare (0.05–0.6%) and is often not correlated with whether or not a patient is on a blood thinner. Still, oculoplastic surgeons prefer to stop anticoagulants and antiplatelet agents, in coordination with cardiologists or neurologists, in the setting of certain procedures such as orbit surgery and blepharoplasty.
indicated for secondary prevention of coronary artery disease in those who have suffered an acute coronary syndrome (ACS) or undergone coronary stent placement (Table 1). Aspirin is also indicated for the primary prevention of acute MI in men over 45 years of age, and primary prevention of stroke in females over 55 years of age [7]. It is also indicated for the primary prevention of heart disease in diabetics over the age of 40 [7]. Antiplatelet agents irreversibly inhibit platelet function for 10 days, the lifespan of a platelet [8]. For patients taking antiplatelet medications
Table 1. Comparison of antiplatelet and anticoagulant agent properties Antiplatelets [4] Mechanism of action
Half-life
Platelet function recovery time
Aspirin
COX-1 inhibition
15–20 min
30% at 48 h
Clopidogrel
P2Y12 receptor inhibition
7–9 h
40% at 72 h
Prasugrel
P2Y12 receptor inhibition
7h
48–72 h
Ticagrelor
P2Y12 receptor inhibition
7–9 h
57% at 24 h
Anticoagulants [5,6] Mechanism of action
Half-life
Time to peak effect
Warfarin
Vitamin K antagonist
20–60 h
72–96 h
Dabigatran
Thrombin inhibitor
12–17 h
2–3 h
Rivaroxaban
Factor Xa inhibitor
9–13 h
0.5–3 h
Apixaban
Factor Xa inhibitor
9–14 h
3h
COX 1, cyclooxygenase 1.
1040-8738 Copyright
Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.
