Mixed Deck — All CVP Topics Flashcards

What is a key regulatory requirement for documenting procedures performed with a cardiopulmonary bypass (CPB) machine?

Answer: Recording detailed patient parameters and any deviations from standard procedures

Detailed documentation of patient parameters and any procedural deviations is a key regulatory requirement in cardiovascular perfusion. This meticulous record-keeping ensures patient safety by allowing for real-time monitoring and post-procedure analysis of the bypass run. It also provides a comprehensive legal and clinical record, essential for accountability, quality assurance, and continuous improvement in patient care.

What is the typical potassium concentration in a standard cardioplegia solution compared to normal plasma?

Answer: Markedly elevated (15–30 mEq/L)

Standard cardioplegia contains 15–30 mEq/L of potassium, roughly 4–6 times the normal plasma level, sufficient to arrest the heart.

What is the typical blood flow rate during adult cardiopulmonary bypass?

Answer: 2.2 to 2.4 L/min/m² of body surface area

The standard perfusion flow rate of 2.2-2.4 L/min/m² maintains adequate organ perfusion during bypass.

What emergency procedures should be followed if there is a power failure during bypass?

Answer: Immediately switch to hand cranking the pump while activating backup power systems

In a power failure, the perfusionist must immediately hand-crank the pump to maintain circulation while backup power (UPS/generator) activates.

What is 'Harlequin syndrome' (North-South syndrome) in VA-ECMO?

Answer: Differential oxygenation between upper and lower body due to competing native cardiac output and ECMO return

Harlequin syndrome occurs when the recovering native heart ejects poorly oxygenated blood to the upper body while ECMO returns well-oxygenated blood to the lower body via the femoral artery.

What is the purpose of in-line blood gas monitoring during bypass?

Answer: Continuous real-time measurement of blood gases, pH, and electrolytes for immediate adjustments

In-line monitoring provides continuous, real-time blood gas data allowing the perfusionist to make immediate adjustments to ventilation and perfusion parameters.

For which type of cardiac procedure is bicaval cannulation with separate SVC and IVC cannulas specifically required?

Answer: Open right heart procedures such as tricuspid valve repair or ASD closure

Bicaval cannulation isolates both venae cavae with snares when the right atrium must be opened, keeping the right heart bloodless and dry for tricuspid valve or septal defect repair.

What is the role of the oxygenator in the bypass circuit?

Answer: To add oxygen and remove carbon dioxide from the blood

The oxygenator functions as an artificial lung, performing gas exchange by adding oxygen and removing carbon dioxide.

The intrinsic coagulation pathway is initiated by:

Answer: Contact activation of Factor XII on negatively charged surfaces

The intrinsic pathway begins with activation of Factor XII (Hageman factor) upon contact with negatively charged surfaces such as exposed subendothelium or foreign materials like CPB tubing.

What is pump flow rate and how is it determined?

Answer: The volume of blood delivered per minute, calculated based on body surface area and desired cardiac index

Pump flow rate is individualized based on the patients body surface area to achieve an appropriate cardiac index, typically 2.2-2.4 L/min/m².

What electrolyte imbalance is most concerning during bypass?

Answer: Hyperkalemia, which can cause cardiac arrhythmias

Hyperkalemia (high potassium) is particularly dangerous during bypass as it can cause fatal cardiac arrhythmias, especially important to monitor given potassium-containing cardioplegia.

On a TEG (thromboelastography) tracing, the Maximum Amplitude (MA) primarily reflects:

Answer: Platelet function and platelet-fibrin clot strength

MA represents the maximum clot strength on TEG and is primarily determined by platelet function (~80%) and fibrin cross-linking (~20%), reflecting overall clot integrity.

What is the role of calcium chloride after bypass?

Answer: To improve cardiac contractility and correct hypocalcemia from citrated blood products

Calcium chloride is given after bypass to improve cardiac muscle contraction and correct low calcium levels that result from citrate in blood products binding calcium.

What is a key indicator of successful hemodynamic monitoring during a CPB procedure?

Answer: Stable blood pressure

Successful hemodynamic monitoring during a CPB procedure is crucial for ensuring adequate organ perfusion. Stable blood pressure is a key indicator, reflecting that the CPB pump is delivering sufficient blood flow and that the patient's vascular tone is appropriately managed. Significant fluctuations in blood pressure can signal issues with the bypass circuit or the patient's physiological response, requiring immediate attention.

What is the primary purpose of an oxygenator in a cardiopulmonary bypass (CPB) system?

Answer: To exchange oxygen and carbon dioxide in the blood

The oxygenator is a critical component of the cardiopulmonary bypass (CPB) system, often referred to as the 'artificial lung.' Its primary purpose is to mimic the gas exchange function of the lungs. It adds oxygen to the patient's deoxygenated blood and simultaneously removes carbon dioxide before the blood is returned to the systemic circulation, ensuring vital gas exchange during heart surgery.

What is the role of a centrifugal pump versus a roller pump in bypass?

Answer: Centrifugal pumps are less likely to cause massive air embolism and generate less hemolysis; roller pumps are simpler and less expensive

Centrifugal pumps generate flow through a spinning vortex and will not pump significant air, while roller pumps use occlusive compression and can pump air if the reservoir empties.

What is myocardial protection during cardiac surgery?

Answer: Techniques to prevent heart muscle damage during the period the heart is stopped

Myocardial protection involves strategies such as cardioplegia to prevent ischemic damage to the heart while it is arrested during surgery.

What is the purpose of a distal perfusion cannula (DPC) placed in the superficial femoral artery during VA-ECMO?

Answer: To perfuse the limb distal to the arterial cannula and prevent ischemia

A DPC is a small-diameter side cannula placed distal to the main arterial cannula, connected to the ECMO circuit to maintain limb perfusion and prevent ischemic complications.

What is the purpose of a bubble detector in a CPB system?

Answer: To detect and alert the presence of air bubbles in the blood circuit

A bubble detector is an essential safety feature integrated into a CPB system. Its primary purpose is to continuously monitor the blood flowing through the circuit for the presence of any air bubbles. If air is detected, the alarm alerts the perfusionist, allowing for immediate intervention to prevent air from entering the patient's systemic circulation, which could cause a severe and potentially fatal air embolism.

What is the purpose of the level detector on the venous reservoir?

Answer: To alarm when blood level drops dangerously low, preventing air from entering the pump

The level detector prevents the catastrophic event of pumping air by alerting when the reservoir level drops below a safe threshold.