Q71 / 110
What is the primary physiologic goal in treating acute right ventricular failure?
Correct answer: B — Reduce right ventricular wall stress
The right ventricle is highly sensitive to afterload, and excessive wall stress worsens ischemia and contractile failure. Therapy therefore focuses on reducing pulmonary vascular resistance, optimizing preload, and supporting contractility when needed. Raising systemic vascular resistance or heart rate indiscriminately can worsen RV performance. The central goal is to restore forward flow while unloading the RV.
Board pearl: Reducing RV wall stress and afterload is central to therapy.
The right ventricle is highly sensitive to afterload, and excessive wall stress worsens ischemia and contractile failure. Therapy therefore focuses on reducing pulmonary vascular resistance, optimizing preload, and supporting contractility when needed. Raising systemic vascular resistance or heart rate indiscriminately can worsen RV performance. The central goal is to restore forward flow while unloading the RV.
Board pearl: Reducing RV wall stress and afterload is central to therapy.
Q72 / 110
What is the preferred anticoagulant for most adult patients on ECMO?
Correct answer: C — Unfractionated heparin
Unfractionated heparin remains preferred in most ECMO settings because it is titratable, has a short half-life, and can be reversed with protamine. This flexibility is especially important in critically ill patients who may oscillate between bleeding and thrombosis risk. Alternative agents are used in selected situations such as suspected HIT or severe heparin resistance. For routine adult ECMO, unfractionated heparin remains first-line.
Board pearl: Unfractionated heparin is the standard first-line anticoagulant for ECMO.
Unfractionated heparin remains preferred in most ECMO settings because it is titratable, has a short half-life, and can be reversed with protamine. This flexibility is especially important in critically ill patients who may oscillate between bleeding and thrombosis risk. Alternative agents are used in selected situations such as suspected HIT or severe heparin resistance. For routine adult ECMO, unfractionated heparin remains first-line.
Board pearl: Unfractionated heparin is the standard first-line anticoagulant for ECMO.
Q73 / 110
Which complication profile best characterizes adult ECMO patients?
Correct answer: D — High bleeding risk and high thrombosis risk
ECMO exposes blood to artificial surfaces that activate coagulation, while anticoagulation itself and ECMO-associated coagulopathy increase bleeding risk. As a result, both thrombosis and hemorrhage are common and may even coexist in the same patient. This is a defining management challenge in ECMO. Protocols therefore focus on balancing two competing hazards rather than eliminating one.
Board pearl: Adult ECMO patients are at substantial risk for both bleeding and thrombosis.
ECMO exposes blood to artificial surfaces that activate coagulation, while anticoagulation itself and ECMO-associated coagulopathy increase bleeding risk. As a result, both thrombosis and hemorrhage are common and may even coexist in the same patient. This is a defining management challenge in ECMO. Protocols therefore focus on balancing two competing hazards rather than eliminating one.
Board pearl: Adult ECMO patients are at substantial risk for both bleeding and thrombosis.
Q74 / 110
A patient develops thrombocytopenia on postoperative day 2 after cardiac surgery. What is the most likely cause?
Correct answer: B — Cardiopulmonary bypass-related platelet consumption
A substantial platelet fall is common during the first 72 hours after cardiac surgery because of hemodilution, platelet activation, and consumption related to cardiopulmonary bypass. True HIT classically presents later, usually with a platelet fall beginning around postoperative days 5 to 10. Recognizing the expected early pattern helps avoid overdiagnosis. Timing is therefore critical when evaluating thrombocytopenia after cardiac surgery.
Board pearl: Early thrombocytopenia after cardiac surgery is usually due to CPB-related platelet consumption, not HIT.
A substantial platelet fall is common during the first 72 hours after cardiac surgery because of hemodilution, platelet activation, and consumption related to cardiopulmonary bypass. True HIT classically presents later, usually with a platelet fall beginning around postoperative days 5 to 10. Recognizing the expected early pattern helps avoid overdiagnosis. Timing is therefore critical when evaluating thrombocytopenia after cardiac surgery.
Board pearl: Early thrombocytopenia after cardiac surgery is usually due to CPB-related platelet consumption, not HIT.
Q75 / 110
Which platelet count pattern is most predictive of true HIT after cardiac surgery?
Correct answer: C — A platelet fall beginning on postoperative days 5 through 10
The platelet count profile most consistent with HIT after cardiac surgery is a delayed fall beginning within the typical immunologic window after heparin exposure. Early postoperative thrombocytopenia is common and nonspecific. Many patients also seroconvert immunologically without having true HIT. The timing of the platelet drop remains one of the most useful clinical clues.
Board pearl: A new platelet fall beginning around postoperative days 5 to 10 is classic for HIT.
The platelet count profile most consistent with HIT after cardiac surgery is a delayed fall beginning within the typical immunologic window after heparin exposure. Early postoperative thrombocytopenia is common and nonspecific. Many patients also seroconvert immunologically without having true HIT. The timing of the platelet drop remains one of the most useful clinical clues.
Board pearl: A new platelet fall beginning around postoperative days 5 to 10 is classic for HIT.