General Surgery — Flashcards

Flashcard 421: If prasugrel must be stopped for surgery, it should be stopped _____ prior

Answer: 7 days

Flashcard 422: If ticagrelor must be stopped for surgery, it should be stopped _____ prior

Answer: 5 days

Flashcard 423: What is the mechanism of action for unfractionated heparin? _____

Answer: Binds to antithrombin III, causing indirect inhibition of factors IIa (thrombin) and Xa

Flashcard 424: Antiplatelet medication (e.g., Aspirin) should be continued through surgery if there is a high _____ risk (e.g., recent coronary stent). Contrastingly, anticoagulants (e.g., Warfarin) are the medications typically temporarily replaced by heparin bridging.

Answer: thrombosis

Extra: In surgical patients, Aspirin is often continued if the risk of a major adverse cardiac event (MACE) outweighs the risk of surgical bleeding. True 'bridging' with heparin is indicated for patients on long-term anticoagulation (Warfarin) with a high risk of thromboembolism (e.g., mechanical heart valves, high-risk AF).

Flashcard 425: The reversal agent of low molecular weight heparin is _____

Answer: IV protamine sulfate

Extra: Note: Protamine sulfate completely neutralizes Unfractionated Heparin (UFH) but only partially neutralizes (approx. 60-80%) the anti-Xa activity of Low Molecular Weight Heparin (LMWH).

Flashcard 426: What is the mechanism of action for low molecular weight heparin? _____

Answer: Indirect inhibition of Xa via activation of antithrombin III

Flashcard 427: Dabigatran is a direct factor _____ inhibitor

Answer: IIa (thrombin)

Flashcard 428: The reversal agent of rivaroxaban is _____

Answer: andexanet alfa (Andexxa)

Flashcard 429: Patients taking DOACs undergoing surgery with a low-risk of bleeding should stop taking the DOAC roughly _____ prior to surgery

Answer: 1 day

Flashcard 430: Vision loss from _____ diabetic retinopathy may result from macular oedema

Answer: nonproliferative