Chapter 22 Anesthesia Practice for Existing Conditions

Question 1

What are the 5 ASA scores?

Answer 1

I = Healthy animal
II = Mild compensated systemic illness
III = Moderate to severe compensated systemic illness
IV = Patient has disease that is constant threat to life
V = moribund patient not expected to survive 24 hours with or without treatment

Question 2

What ASA score would a patient with CHF, GDV, sepsis, pneumothorax be?

Answer 2

ASA IV

Question 3

What ASA score would a patient with heart disease, CKD, liver disease, diabetes mellitus be?

Answer 3

ASA III

Question 4

What ASA score would an obese or hypothyroid patient be?

Answer 4

ASA II

Question 5

Why can ketamine be useful in premedication for patients with allergic airway disease?

Answer 5

Can cause bronchodilation

Question 6

What is the maximum allowable intraabdominal pressure in laparoscopic procedures and why?

Answer 6

14cm H2O
Above this, renal blood flow is compromised
Increased intrathoracic pressure may lead to hypoventilation

Question 7

What drug has been shown to adversely affect neonate survival?

Answer 7

Xylazine

Question 8

5 causes of hypoxemia

Answer 8

1. Hypoventilation
2. Diffusion impairment
3. Right to left shunt
4. Low FiO2 (inspired oxygen)
5. V/Q mismatch

Question 9

Which causes of hypoxemia respond well to supplemental oxygen?

Answer 9

• Hypoventilation
• Decreased FiO2
• Diffusion barrier impairment

Question 10

What are causes of high V/Q mismatch? Low?

Answer 10

High = PTE
Low = pnemonia, alveolar collapse (eg. mass, atelectasis)

Question 11

What can occur once malignant hyperthermia is triggered?

Answer 11

Hypercapnea, hyperthermia, and muscle rigidity
Cardiac arrythmias and death can occur

Question 12

What is malignant hyperthermia?

Answer 12

Inherited condition that can result in extreme hypermetabolic state under anesthesia

Question 13

What is the pathophysiology behind malignant hyperthermia?

Answer 13

• Defect in cellular ryanodine receptor (involved in induced Ca release in muscles)
• Excessive and dysregulated intracellular calcium causes muscle spasm, rigidity, and hypermetabolic state

Question 14

How is malignant hyperthermia frequently recognized?

Answer 14

Abrupt increase in ETCO2, followed by elevation in body temperature and HR

Question 15

How do you treat malignant hyperthermia?

Answer 15

Discontinue inhalant
IV Dantrolene (stabilizes sarcoplasmic reticulum and decreases Ca release)