Exam 1-Anticoagulant/Antiplatelet Considerations Flashcards
(50 cards)
What is the primary neurological risk of performing neuraxial anesthesia on a patient taking anticoagulants?
Epidural hematoma, which can compress the spinal cord leading to ischemia and permanent neurological damage.
What is the critical time window for surgical decompression in a patient with an epidural hematoma?
Within 8 hours to optimize recovery chances.
Why are patients with cardiac stents at particular risk when considering neuraxial anesthesia?
Stopping anticoagulants increases stent thrombosis risk, while continuing them increases risk of epidural hematoma.
What differentiates the need to hold aspirin before a procedure based on the type of prophylaxis?
Stopping aspirin used for secondary prophylaxis carries a higher risk (e.g., 10% of acute CV syndromes follow aspirin withdrawal).
For how long should aspirin typically be held before high-risk or intermediate-risk surgical procedures?
4-6 days.
Which glycoprotein IIb/IIIa antagonist requires the longest hold time before neuraxial anesthesia?
Abciximab (ReoPro), which should be held for 24-48 hours.
What are the recommended hold times for clopidogrel, prasugrel, and ticlopidine before regional anesthesia?
Clopidogrel: 5-7 days, Prasugrel: 7-10 days, Ticlopidine: 10 days.
At what heparin dose does the hold time before neuraxial anesthesia extend to 24 hours?
Therapeutic dose >20,000 U daily or in pregnant patients.
What lab value should be checked before central neuraxial block if unfractionated heparin has been used for more than 4 days?
Platelet count.
How long should you wait after a prophylactic vs. therapeutic dose of LMWH before placing a neuraxial block?
Prophylactic: 12 hours; Therapeutic: 24 hours.
What INR value must be verified before placing a neuraxial block in a patient previously on warfarin?
INR must be less than 1.5.
Which anticoagulant class is absolutely contraindicated with neuraxial anesthesia and why?
Thrombolytic agents, because they cause clot dissolution via plasmin activation, posing severe bleeding risk.
What is the recommended discontinuation period before neuraxial anesthesia for patients taking direct oral anticoagulants (DOACs)?
At least 72 hours.
Can neuraxial anesthesia be performed on a patient taking herbal therapies such as garlic or ginseng?
Yes, as long as they are not on other blood-thinning drugs.
What anticoagulant mechanism is shared by both low molecular weight heparins and direct oral anticoagulants?
Inhibition of factor Xa.
A patient is scheduled for elective hip replacement and takes clopidogrel for a recent MI. When should clopidogrel be discontinued prior to spinal anesthesia?
Clopidogrel should be held for 5-7 days before neuraxial anesthesia to minimize the risk of epidural hematoma.
You are planning to place an epidural in a patient receiving low-dose subcutaneous heparin (5,000 U BID) for DVT prophylaxis. How long should you wait after the last dose?
Wait at least 4-6 hours after the last low-dose heparin dose before performing neuraxial anesthesia.
An elderly patient on enoxaparin for DVT prophylaxis is scheduled for spinal anesthesia. What additional factor must you consider before proceeding?
Consider renal function and possibly check anti-factor Xa levels if renal insufficiency is suspected.
A patient on warfarin presents for emergency spinal anesthesia. Their INR is 1.7. What is your next step?
Spinal anesthesia is contraindicated; INR must be <1.5 to proceed safely.
You are asked to evaluate a patient who recently received a thrombolytic agent for stroke. Can you perform a neuraxial block?
No, thrombolytics are an absolute contraindication due to the high risk of bleeding complications.
For a patient on ticlopidine scheduled for lumbar epidural steroid injection, how long must the medication be held?
Ticlopidine should be discontinued for at least 10 days prior to neuraxial anesthesia.
A patient is taking aspirin 81 mg for secondary prevention of MI. You are planning spinal anesthesia for a low-risk urologic procedure. What is your approach?
Do not hold aspirin; for central neuraxial blocks, no additional precautions are needed with low-dose aspirin used for secondary prevention.
A patient has been receiving IV unfractionated heparin at therapeutic doses. What is the required hold time before neuraxial block placement?
Hold for at least 24 hours before performing neuraxial anesthesia.
What should be done before placing a neuraxial block in a patient on daily subcutaneous LMWH for more than four days?
Check a platelet count to rule out heparin-induced thrombocytopenia.
