Cardioplegia Delivery Methods Flashcards
7 cards from real CCP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Cardioplegia Delivery Methods flashcards as text
In a patient with a totally occluded left anterior descending artery, antegrade cardioplegia via the aortic root will most reliably protect which territory?
Answer: Right ventricle and inferior wall supplied by the RCA
In total LAD occlusion, antegrade aortic root cardioplegia cannot reach the LAD territory directly; the RCA and RCA-supplied territories receive more reliable protection.
The typical blood-to-crystalloid ratio used in 4:1 blood cardioplegia refers to:
Answer: 4 parts blood to 1 part crystalloid cardioplegia concentrate
In 4:1 blood cardioplegia, four parts of oxygenated blood are mixed with one part of crystalloid cardioplegia concentrate, providing oxygen-carrying capacity.
Which finding during cardioplegia delivery MOST warrants concern about inadequate myocardial protection?
Answer: Electromechanical activity returning within 10–15 minutes of last dose
Return of electromechanical activity (electrical activity or mechanical contraction) before the next scheduled dose indicates inadequate potassium concentration or cardioplegia washout.
When performing selective antegrade ostial cardioplegia, the perfusionist must be most cautious about:
Answer: Delivering too much volume too quickly, causing coronary dissection or intimal injury
Selective ostial cannulation creates risk of coronary dissection or intimal injury if delivery pressure or technique is not carefully managed.
Which cardioplegia strategy is most appropriate for a reoperative coronary artery bypass graft (CABG) patient with multiple patent vein grafts?
Answer: Combined antegrade via native ostia and retrograde, supplemented by vein graft cannulation
Redo CABG patients benefit from combined delivery supplemented with direct vein graft cannulation to ensure cardioplegia reaches territories supplied by grafts and native vessels.
pH-stat blood gas management during hypothermic cardioplegic arrest results in:
Answer: Relative acidosis and increased cerebral blood flow due to CO2 retention
pH-stat management adds CO2 to maintain pH 7.40 at actual temperature, causing relative acidosis and cerebral vasodilation with higher cerebral blood flow.
What is the primary purpose of adding glutamate and aspartate to blood cardioplegia solutions?
Answer: Provide amino acid substrates for anaerobic energy production and enhance aerobic recovery
Glutamate and aspartate serve as substrate precursors for the Krebs cycle, supporting aerobic metabolic recovery and improving post-ischemic myocardial function.