Simulation Exam 3

Question 1

Which of the following values most accurately represents the normal average total cerebral blood flow?

Answer 1

About 15 percent of the cardiac output goes to the brain, or about 50 mL/100g/min.

Question 2

In performing an intercostal nerve block, it is important to remember that

Answer 2

the nerve travels just below the artery on the inferior surface of the rib

The intercostal neurovascular bundle travels on the inferior surface of the rib. From superior to inferior in the bundle are the vein, artery, and nerve.

Question 3

By inserting a needle 2 cm at the inguinal crease just medial to the anterior superior iliac spine and injecting 5-10 mL of local anesthetic after the needle penetrates the fascia lata, you would be attempting to block which nerve?

Answer 3

Lateral femoral cutaneous

The lateral femoral cutaneous nerve emerges underneath the inguinal ligament and becomes superficial inside the fascia lata near the anterior superior iliac spine.

Question 4

The injection of a 5-8 mL of local anesthetic subcutaneously near the inferior border of the medial malleolus would anesthetize which nerve?

Answer 4

Saphenous

The injection of local anesthetic superficially near the inferior border of the medial malleolus will anesthetize the saphenous nerve.

Question 5

In the supine position, the most dependent area of the spinal column occurs at about the level of

Answer 5

T4

Normally, in the supine position, the most dependent portion of the spinal column occurs at T4.

Question 6

The classic 3 mL test dose for epidural anesthesia contains

Answer 6

epinephrine 15 mcg

The standard test dose for epidural anesthesia contains 3 mL of 1.5% lidocaine and 1:200,000 epinephrine or 15 mg/mL of lidocaine and 5 mcg/mL of epinephrine. Thus the total test dose contains 45 mg lidocaine and 15 mcg epinephrine.

Question 7

Severe obesity is commonly associated with

Answer 7

Hyperinsulinemia, hypertension, and increased mineralocorticoid levels are all associated with severe obesity. In order to develop and sustain the increased adipose tissue, new vessels must be formed. The associated increases in circulatory requirements result in an increase in cardiac output of about 0.1 L/min for every additional kilogram of body fat.

Question 8

The presence of a Q wave on the electrocardiogram is considered pathologic when its duration exceeds

Answer 8

0.04

A Q wave on the electrocardiogram is considered pathologic when its duration is 0.04 seconds or greater which corresponds to 1 mm wide on the standard tracing.

Question 9

Which of the following is NOT one of the requirements for the diagnosis of a new myocardial infarction?

Answer 9

Ejection fraction < 40%

The diagnosis of an acute MI requires that any one of the following criteria be met: 1) the rise and fall of cardiac markers (especialy troponin), symptoms of ischemia, ECG changes indicative of ischemia, Q waves on the ECG, or imaging evidence of myocardial damage or wall motion abnormalities.

Question 10

Which of the following antiplatelet drugs used in patients with a history of myocardial ischemia works by blocking adenosine diphosphate receptors?

Answer 10

Clopidogrel

Clopidogrel and ticlopidine inhibit platelet aggregation by blocking adenosine diphosphate receptors. Abciximab and eptifibatide inhibit platelet adhesion, activation, and aggregation by antagonizing platelet glycoprotein IIa/IIIb receptors.

Question 11

Which of the following pharmacologic treatments may result in increased intracranial pressure when treating hypertensive emergencies associated with encephalopathy?

Answer 11

Nitroprusside may increase intracranial pressure and therefore must be used cautiously in the treatment of hypertensive crises associated with encephalopathy.

Question 12

Which of the following statements regarding intraocular pressure is true?

Answer 12

Dextran decreases intraocular pressure

The normal intraocular pressure is about 10 to 21 mmHg and pressures above 22mmHg is considered intraocular hypertension. Intraocular pressure is higher in the morning, presumably from venous congestion due to the eyes being closed. Dextran, mannitol, urea, and sorbitol all decrease intraocular pressure by exerting a hyperosmotic effect that decreases aqueous humor formation.

Question 13

You are preparing to perform nasal intubation for a patient undergoing dental surgery and are administering 4% cocaine intranasally to constrict the nasal passages. What is the maximum volume of the cocaine solution that can be administered?

Answer 13

The maximum amount of 4% cocaine solution that may be administered for vasoconstriction of the nasal passages is 4 mL.

Question 14

All of the following statements regarding pediatric anesthesia are true except:

Answer 14

Hepatic function is typically mature within the first 24 hours after delivery

Hepatic function is immature in the newborn and some hepatic pathways do not mature until after a year of age. Levels of albumin and other serum proteins are low in the full-term infant and result in a higher free fraction of many protein-bound drugs.

Question 15

Which of the following routes of administration of midazolam would be least recommended for a five year-old patient?

Answer 15

Midazolam can be administered oraly, rectally, nasally, intravenously, or intramuscularly. The IM route is not recommended because of pain and the risk of a sterile abscess.

Question 16

Which of the following would be an appropriate change to your anesthetic plan in a patient undergoing bilateral adrenalectomy for Cushing’s disease?

Answer 16

Avoid high doses of non-depolarizing muscle relaxants

Patients with Cushing’s disease have increased serum cortisol levels resulting in hypokalemia, hyperglycemia, and skeletal muscle relaxation which may require a decreased non-depolarizing muscle relaxant dose. Etomidate may decrease adrenal function temporarily, and although it does not need to be avoided, it is unlikely it would produce any therapeutic effect in these patients. Because patients undergoing bilateral adrenalectomy exhibit a rapid decrease of serum cortisol levels, steroid replacement therapy should be initiated prior to or during surgery. Because of the tendency toward skeletal muscle weakness, it is recommended that patients with Cushing’s disease be mechanically ventilated whenever possible.

Question 17

The critical level for the development of autonomic hyperreflexia due to a spinal cord lesion is

Answer 17

T6

Autonomic hyperreflexia is seen in approximately 85% of all patients with a spinal cord lesion at or above T6. Lesions at or below T10 do not consistently produce symptoms of autonomic hyperreflexia.

Question 18

Which of the following agents would be the most appropriate for performing controlled hyp

Answer 18

Sodium nitroprusside

Although numerous agents such as calcium channel blockers, volatile agents, and hydralazine are acceptable for producing controlled hypotension, the rapid onset and short duration of action of sodium nitroprusside and nitroglycerin make them most suitable for controlled hypotensive techniques.

Question 19

What primarily explains the prolonged duration of midazolam in an elderly patient?

Answer 19

decreased hepatic perfusion

The duration of action of midazolam is increased in the elderly. The clearance of the drug is reduced by as much as 30 percent due to a decrease in hepatic mass and perfusion. The recommended dose for a 90 year-old should be reduced by 75 percent from that acceptable for a 20 year-old.

Question 20

A pediatric patient is undergoing general anesthesia for repair of a right-to-left shunt. You would expect the speed of inhalation induction to be

Answer 20

slower

If a right-to-left shunt is present, an inhalation induction proceeds more slowly because the anesthetic concentration of arterial blood increases more slowly. The opposite is true with a left-to-right shunt because the rate of transfer of anesthetic from the lungs to the blood is more rapid. This effect is rarely evident in the clinical setting, however.

Question 21

Which laser is capable of deep tissue penetration and requires specially designed goggles to prevent retinal damage from stray beams?

Answer 21

Neodymium-yttrium-aluminum-garnet (Nd:YAG) laser

Nd:YAG lasers are poorly absorbed by water, but well-absorbed by pigmented tissues. Because of this, it is able to penetrate more deeply into body cavities and is well-suited for de-bulking hepatic, splenic, esophageal, and bladder tumors. Nd:YAG lasers are capable of causing retinal damage and specially designed goggles must be worn when they are in use. CO2 lasers have a shallow burn depth and are extremely accurate. Helium-neon lasers are often used to direct CO2 lasers.

Question 22

Which statement is true of EEG monitoring during a carotid endarterectomy?

Answer 22

It does not monitor deep brain structures

An EEG monitors the electrical activity of cortical structures only and would miss a stroke in deeper brain structures. EEG monitoring has a poor sensitivity for identifying cerebral ischemia. The EEG can also change due to alterations in anesthetic depth or if hypothermia is present.

Question 23

During repair of a tracheoesophageal fistula,

Answer 23

. the bevel of the endotracheal tube should face anteriorly after it is passed through the cords

During repair of a tracheoesophageal fistula, the endotracheal tube should be advanced intentionally into the right mainstem bronchus and then slowly withdrawn until the first point at which breath sounds are heard in both lung fields. Then the bevel of the tube should be rotated so that it faces anteriorly. This is done to prevent ventilation of the fistula. Placement of the precordial stethoscope over the left lung alerts the anesthetist in the event the endotracheal tube migrates into the right mainstem bronchus. Tracheoesophageal fistula is associated with subglottic stenosis which may require placement of a smaller than usual endotracheal tube.

Question 24

You are performing an epidural block on an obese patient. As part of the procedure, you should

Answer 24

have the patient sit up longer after injection

The obese patient should be in the sitting position when the epidural is placed to help in identifying landmarks. Because rostral spread of the anesthetic is more prevalent in obese patients and they are more prone to suffer respiratory symptoms as a result, you should have them sit up for a longer period of time after injection.

Question 25

Which of the following 12-lead ECG characteristics are consistent with a left bundle branch block?

Answer 25

RS > 0.12 seconds

The characteristics consistent with a left bundle branch block are: QRS > 0.12 secs, lack of septal Q waves in V4-V6, I and aVL, RR’ QRS pattern in I, aVL, and V4-V6, and secondary ST or T wave changes in I, aVL, and V4-V6. A deep, rounded S wave in leads I and aVL is typical of a right bundle branch block, while a V5 amplitude > 26 mm is one of the characteristics of left ventricular hypertrophy.

Question 26

Chronic bronchitis differs from emphysema in that patients with bronchitis

Answer 26

have an elevated hematocrit

Patients with chronic bronchitis typically exhibit frequent cough, copious sputum, an elevated hematocrit, increased markings (not hyperinflation) on chest x-ray, elevated PaCO2, normal elastic recoil, and increased airway resistance. In contrast, patients with emphysema have minimal sputum production with a less frequent cough, a normal hematocrit and a PaCO2, decreased elastic recoil, hyperinflation on chest x-ray and a normal to slightly increased airway resistance.

Question 27

Which of the following is associated with a higher risk of placenta accreta in parturients already presenting with placenta previa?

Answer 27

History of multiple cesarean sections

Patients with placenta previa who have had one previous c-section are more likely to have placenta accreta, (penetration of the myometrium by placental villi).

Question 28

Which of the following illustrates a correct understanding of the anesthestic management of the patient with cerebral palsy? (select two)

Answer 28

The patient is at severe risk for gastric aspiration
Patients with cerebral palsy are more at risk for hypothermia

Even though they may suffer muscle weakness and spasticity, patients with cerebral palsy do not have an exaggerated hyperkalemic response to succinylcholine, nor are they more susceptible to malignant hyperthermia.They are susceptible of hypothermia and require close temperature monitoring. Abrupt discontinuation of baclofen can result in withdrawal symptoms such as itching, confusion, hallucinations, and seizures. Gastric reflux is often severe enough that surgery to correct it is necessary.

Question 29

Patients with systemic lupus erythematosus often exhibit

Answer 29

a restrictive respiratory defect

Patients with SLE are prone to pleural effusion, pneumonitis, alveolar hemorrhage, and pulmonary hypertension. The end result is a restrictive defect.

Question 30

Which of the following statements regarding infrared gas analyzers is true?

Answer 30

Ethanol can be falsely detected as a volatile agent

Infrared gas monitors are small and portable, they have a quick response time, a short warm-up time, and do not need to be connected to a scavenger because the analyzed gases can be returned to the circuit. Argon and nitric oxide don’t interfere with readings, but other substances such as ethanol, ether, paraldehyde, and acetone can be incorrectly detected as volatile agents. Although the response time is fast, it may not be fast enough to accurately analyze volatile agent levels if the respiratory rate is very high. Handheld two-way radios may interfere with the analyzer causing CO2 readings to be falsely elevated.

Question 31

Hyperkalemia due to hypoaldosteronism is most noted to produce

Answer 31

Hyperkalemia due to hypoaldosteronism will often produce heart block.

Question 32

Which diuretic inhibits sodium reabsorption by limiting the number of open sodium channels in the epithelium of the cortical collecting ducts?

Answer 32

amiloride

Unlike spironolactone, triamterene and amiloride do not rely on aldosterone activity. They inhibit sodium reabsorption and potassium secretion by limiting the number of open sodium channels in the epithelium of the cortical collecting duct.

Question 33

What is the recommended minimum recovery period before a CRNA who has been treated for narcotic diversion and substance abuse should return to clinical anesthesia?

Answer 33

1 year

Individuals with the highest success rate of rehabilitation have completed a minimum of 28 inpatient treatment days and a total of at least 90 treatment days. A minimum recovery period of 1 year is recommended prior to returning to clinical anesthesia. Varying state laws can prohibit the anesthesia provider’s ability to return to their full scope of practice, however.