CTP Organ Preservation Techniques 2

Question 1

Which component of University of Wisconsin (UW) solution is responsible for preventing cell swelling during cold ischemia?

Accepted Answer

Hydroxyethyl starch

Answer

Hydroxyethyl starch is the impermeant colloid in UW solution that prevents cell swelling by maintaining oncotic pressure.

Question 2

During normothermic machine perfusion (NMP) of the liver, which parameter best indicates adequate cellular metabolism?

Accepted Answer

Perfusate lactate clearance

Answer

Lactate clearance during NMP reflects hepatocyte metabolic activity and is a key viability marker.

Question 3

What is the primary rationale for using pulsatile flow rather than continuous flow in hypothermic machine perfusion (HMP) of kidneys?

Accepted Answer

It better mimics physiological conditions and reduces vascular resistance

Answer

Pulsatile flow in HMP mimics the cardiac cycle, reduces vascular resistance, and improves nutrient delivery to renal tissue.

Question 4

Which enzyme system is most critically impaired when ATP is depleted during warm ischemia?

Accepted Answer

Na⁺/K⁺-ATPase pump

Answer

The Na⁺/K⁺-ATPase pump requires ATP to maintain ion gradients; its failure leads to cell swelling and irreversible injury.

Question 5

In pancreas preservation, what is the maximum recommended cold ischemia time to optimize islet cell viability?

Accepted Answer

12 hours

Answer

Cold ischemia time for pancreas preservation should ideally not exceed 12 hours to maintain islet cell function.

(CTP) Certified Transplant Preservationist Practice Test