Chapter 158 Ischemia-Reperfusion Injury

Question 1

Describe the movement of intracellular and extracellular ions during ischemia.

Answer 1

Potassium efflux, movement of Na/Cl/Ca into cells. Increased intracellular sodium concentrations induce water influx by diffusion, result in cellular swelling.

Question 2

What molecule is a major player in canine reperfusion injury?

Answer 2

Xanthine oxidase

Question 3

What mediates the majority of mucosal and microvascular injury?

Answer 3

Neutrophil

Question 4

What’s the time frame of reperfusion injury related to GDV?

Answer 4

Within 3 hours of decompression

Question 5

What is the difference between thrombosis and embolism?

Answer 5

Thrombosis occurs when a thrombus, or blood clot, develops in a blood vessel and reduces the flow of blood through the vessel. Embolism occurs when a piece of a blood clot, foreign object, or other bodily substance becomes stuck in a blood vessel and largely obstructs the flow of blood.

Question 6

What is reported complication of thrombolytic therapy>

Answer 6

Hyperkalemia, azotemia, neurological signs, arrhythmias, acidosis, sudden death

Question 7

What are the multimodal effects of lidocaine

Answer 7

1. fast sodium channel antagonist
2. class 1b antiarrhythmic agent
3. antagonist of ATP-sensitive potassium channel
4. scavenger of superoxide and hydroxyl radicals
5. inflammatory modulator
6. inhibitor of granulocyte

Question 8

What were the suggested benefits of lidocaine on GDV?

Answer 8

When administered prior to decompression and hence before the likely peak of reperfusion injury, lidocaine treatment significantly decreased the incidence of kidney injury, cardiac arrhythmias, and coagulation disorders, and shorten hospitalization.

Question 9

What is the theoretical benefit of NAC?

Answer 9

NAC is a glutathione precursor that penetrates into cells and acts to replenish intracellular glutathione concentration.

Question 10

What are the disorders known to induce ischemia-reperfusion injury?

Answer 10

GDV, ATE, Myocardial infarction, crush injury, bite trauma, TBI, spinal cord injury, myelomalacia, ischemic myelopathy

Question 11

What are the proposed therapies for IRI?

Answer 11

NAC, lidocaine, ischemic preconditioning, deferoxamine, allpurinol, cyclosporine, remifentanil