ECMO Pharmacology and Drug Management Flashcards

Which pharmacokinetic parameter is most significantly increased by ECMO in critically ill patients?

Answer: Volume of distribution (Vd)

ECMO increases the apparent volume of distribution by sequestering lipophilic drugs into circuit components and the large priming volume.

Corticosteroid therapy in VA-ECMO patients with refractory vasodilatory shock is aimed at treating:

Answer: Critical illness-related corticosteroid insufficiency (CIRCI)

CIRCI causes impaired cortisol response to stress, and hydrocortisone supplementation can restore vasopressor responsiveness in refractory shock.

Argatroban, used in HIT patients on ECMO, is monitored using which laboratory test?

Answer: Activated clotting time (ACT) or aPTT

Argatroban is monitored via aPTT (target 1.5–3× baseline) or ACT, as it directly inhibits thrombin and prolongs clot-based assays.

Milrinone is sometimes used in ECMO patients because it improves cardiac function by:

Answer: Inhibiting phosphodiesterase III to increase cAMP and improve contractility with vasodilation

Milrinone's PDE-III inhibition raises intracellular cAMP, producing positive inotropy and systemic vasodilation, useful for low cardiac output states.

Which packed red blood cell (pRBC) transfusion threshold is commonly targeted in stable VV-ECMO patients without active hemorrhage?

Answer: Hgb <10 g/dL

Most ECMO centers target hemoglobin >10 g/dL to optimize oxygen delivery through the circuit to the patient.

Prolonged aminoglycoside use in ECMO patients requires monitoring for which organ-specific toxicity?

Answer: Nephrotoxicity and ototoxicity

Aminoglycosides accumulate in renal tubular cells and cochlear tissue, causing dose-dependent nephrotoxicity and ototoxicity requiring TDM.