Intraoperative Procedures & Patient Monitoring 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 Intraoperative Procedures & Patient Monitoring flashcards as text
During cardiopulmonary bypass, which parameter best reflects cerebral oxygen delivery adequacy when using near-infrared spectroscopy (NIRS)?
Answer: Regional cerebral oxygen saturation (rSO2) >50% of baseline
NIRS-derived rSO2 dropping below 50% of the patient's baseline value is the accepted threshold indicating inadequate cerebral oxygen delivery.
A patient on CPB develops sudden onset of bright red arterial line blood and a marked increase in arterial line pressure. The most likely cause is:
Answer: Aortic dissection
Sudden bright red blood in the arterial line combined with a pressure spike suggests aortic dissection, where the cannula tip has entered the false lumen.
Which of the following is the primary purpose of administering mannitol during cardiopulmonary bypass?
Answer: Promote osmotic diuresis and free radical scavenging
Mannitol is used during CPB as an osmotic diuretic to maintain urine output and as a free radical scavenger to reduce reperfusion injury.
During rewarming on CPB, the maximum recommended temperature gradient between the heat exchanger water and the patient's blood temperature is:
Answer: 10°C
A water-to-blood temperature gradient exceeding 10°C risks gas coming out of solution and forming emboli in the blood.
The activated clotting time (ACT) target for full heparinization during cardiopulmonary bypass is generally:
Answer: >400 seconds
Most centers target an ACT greater than 400 seconds (some use 480 seconds) before initiating CPB to prevent clot formation in the circuit.
Which physiologic change is expected when transitioning from normothermic to hypothermic CPB?
Answer: Decreased oxygen consumption and decreased CO2 production
Hypothermia reduces cellular metabolic rate, decreasing both oxygen consumption (VO2) and carbon dioxide production (VCO2).
A perfusionist notices increasing arterial line pressure with unchanged pump flow. The most appropriate initial response is to:
Answer: Check for arterial cannula kinking or obstruction
Rising arterial line pressure at constant flow suggests increased resistance in the arterial line, most commonly from cannula kinking, malpositioning, or aortic obstruction.