Question Set 1

Question 1

Select the correct statements regarding cerebral metabolism include:

A: the brain can only utilize glucose as an energy source
B: forty percent of brain glucose consumption is anaerobically metabolized
C: hyperglycemia can reduce the damage from focal hypoxic injury
D: the adult brain consumes approximately 50 ml/min of oxygen

Answer 1

D: the adult brain consumes approximately 50 ml/min of oxygen
The adult brain consumes about 20% of the total body oxygen (50 ml/min).

Neuronal cells normally utilize glucose as their energy source, but can also utilize ketone bodies and lactate. Hyperglycemia has been shown to worsen global and focal hypoxic brain injury.

Question 2

In the thromboelastogram below, clot strength is best represented by?

Answer 2

E.

The maximum amplitude (E) is a measure of the strength of the fully formed clot. It reflects primarily platelet number and function although it also requires proper fibrin formation to achieve normal values.

Question 3

Venous irritation associated with the injection of diazepam and lorazepam is secondary to?

Answer 3

The presence of propylene glycol as a solvent!

The insolubility of diazepam and lorazepam in water requires that parenteral preparations contain propylene glycol, which has been associated with venous irritation.

Question 4

The effects of barbiturates on ischemic areas of the brain include?

Answer 4

Redirection of blood flow to the ischemic areas!

Barbiturates cause cerebral vasoconstriction in normal areas. These agents tend to redistribute blood flow to ischemic areas in what is sometimes referred to as a reverse steal phenomenon or Robin Hood effect.
Ischemic areas remain maximally dilated and unaffected by the barbiturate.

Question 5

During the administration of general anesthesia for a radical prostatectomy, the rhythm strip below is obtained. The most appropriate therapeutic measures at this time would include?

A: Requesting the use of a bipolar cautery
B: Applying a magnet over the chest
C: Stopping the case and asking for cardiac clearance
D: Nothing, proceed with case

Answer 5

A: Requesting the use of a bipolar cautery

This rhythm strip indicates a paced rhythm with clearly visible pacer spikes. Electrical interference from the electrocautery can be interpreted as myocardial activity and can suppress the pacemaker generator. The use of a bipolar cautery will reduce the electrical interference produced; if that is not possible, then pure cut is better than “blend” or “coag.”

Question 6

Reactants that are regenerated during the absorption of carbon dioxide by soda lime include?

A: Calcium Hydroxide (Ca(OH)2)
B: Oxygen (O2)
C: Sodium Hydroxide (NaOH)
D: Calcium Carbonate (CaCO3)

Answer 6

C: Sodium Hydroxide (NaOH)

Both water and sodium hydroxide are initially required during the absorption of carbon dioxide by soda lime, but then are regenerated.

Question 7

Anesthetic complications associated with hypothyroidism include?

A: Delayed induction
B: Uncontrolled blood pressure
C: Difficult extubation
D: Difficulty with intubation and airway management

Answer 7

D. Difficulty with intubation and airway management!

Potential problems of hypothyroidism
include hypoglycemia, anemia, hyponatremia and difficulty
during intubation because of a large tongue or the presence of a goiter. Hypothermia secondary to a low metabolic rate is a common postoperative complication.

Question 8

In the graph of cerebral blood flow below, PaO, would best be represented by curve:

Answer 8

A

Curve A best represents the effects of changing oxygen tensions on cerebral blood flow. Hypoxemia causes a
significant increase in CBF to meet the brain’s metabolic demand. Hyperoxia, however, causes little change in CBF.

Question 9

Maternal mortality associated with amniotic fluid embolization is?
A: 10-15%
B: 20-25%
C: 40-45%
D: Greater than 50%

Answer 9

D: Greater than 50%

Amniotic fluid embolism is rare with a occurrence of about 1:20,000. However, it carries a very high mortality; some studies quoting as much as 86%. Mortality within the first hour after onset is about 50%.

Question 10

Dextran 40 has been shown to improve microcirculation by:
A: Reducing blood density
B: Increasing blood density
C: Decreasing blood viscosity
D: Increasing blood viscosity

Answer 10

D: Decreasing blood viscosity

Dextran 40 has been shown to improve microcirculation presumably by decreasing blood viscosity thereby improving laminar flow in the microcirculatory beds. Both Dextran 40
Dextran 40 and Dextran 70 possess antiplatelet effects and may interfere with blood typing.

Question 11

In the thromboelastograms below, thrombocytopenia is best represented by:
A
B
C
D

Answer 11

C

Thrombocytopenia causes an overall reduction in clot strength shown as a narrowing in the thromboelastogram.

Question 12

The highest level of protein binding is seen with:

A: Procaine
B: Lidocaine
C: Mepivacaine
D: Bupivacaine

Answer 12

B. Bupivacaine

The physicochemical property that determines the duration of action of a local anesthetic is lipid solubility, which is directly correlated with plasma protein binding. Bupivacaine and levobupivacaine have the highest degree of protein binding (97%).

Question 13

Where do ninety percent of congenital diaphragmatic hernias occur?

Answer 13

Left-sided herniation through the posterolateral foramen of Bochdalek accounts for 90% of diaphragmatic hernias. Hypoxia, scaphoid abdomen and evidence of bowel in the thorax are the hallmarks of diaphragmatic herniation. Peak airway pressures should not exceed 30 cm H20 to minimize the risk of pneumothorax during surgical correction.

Question 14

Cholinesterase inhibitors that freely cross the blood-brain barrier include:

A: Pyridostigmine
B: Physostigmine
C: Neostigmine
D: All of the above

Answer 14

B: Physostigmine
Physostigmine is a teritary amine and has a carbamate group, but no quaternary ammonium. Therefore, it is lipid soluble and is the only clinically available cholinesterase inhibitor that freely passes the blood-brain barrier.

Question 15

The perception of an ordinarily non-noxious stimulus as pain is referred to as:

A: Allodynia
B: Dysesthesia
C: Hyperalgesia
D: Anesthesia dolorosa

Answer 15

A: Allodynia
Allodynia is the perception of non-noxious stimuli as pain. Dysesthesia is an unpleasant sensation without a stimulus. Hyperesthesia is an increased response to a mild stimulus. Anesthesia dolorosa is pain in an area that lacks sensation.

Question 16

Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above:

A: 25 mmHg
B: 20 mmHg
C: 15 mmHg
D: 10 mmHg

Answer 16

C: 15 mmHg
Intracranial hypertension is defined as a sustained increase in intracranial pressure (ICP) above 15 mm Hg.
Uncompensated increases in tissue or fluid within the rigid intracranial vault produce the sustained pressure elevations.

Question 17

A 76-year-old man is scheduled for a hemicolectomy. His past medical history is significant for third degree heart block treated with a permanent pacemaker. Problems with electrocautery use in this patient can be minimized by:

A: Placing the grounding pad near the pacemaker
B: Using infrequent bursts of longer duration
C: The use of a bipolar cautery
D: Reducing the surface area of the return electrode

Answer 17

C.

Electrical interference from the electrocutery can be interpreted by the pacemaker as myocardial activity and suppress pacemaker activity. These problems can be minimized by limiting use to short bursts, placing the grounding pad as far from the pacemaker as possible and using a bipolar cautery.

Question 18

The most severe transfusion reactions are due to:
A: ABO incompatibility
B: Rh incompatibility
C: Febrile reactions
D: Non-ABO hemolytic reactions

Answer 18

A: ABO incompatibility

The most severe transfusion reactions are due to ABO incompatibility. Naturally acquired antibodies can react against the transfused antigens, activate complement and result in intravascular hemolysis.

Question 19

The postretrobulbar block apnea syndrome:
A: Is likely secondary to intravascular injection
B: Most commonly occurs during or immediately after injection
C: Is associated with unconsciousness
D: Carries a high morbidity and mortality

Answer 19

C: Is associated with unconsciousness

The postretrobulbar block apnea syndrome is probably due to injection of local anesthetic into the optic nerve sheath, with spread into the CSF. The CNS is exposed to high concentrations of local anesthetic leading to apprehension and unconsciousness. Apnea occurs within 20 minutes and resolves within an hour.
Treatment is supportive.

Question 20

Physiologic effects of electroconvulsive therapy (ECT) include an:
A: Initial sympathetic response with sustained tachycardia
B: Initial sympathetic discharge followed by a sustained parasympathetic response
C: Initial parasympathetic discharge followed by a sustained sympathetic response
D: Initial parasympathetic response with sustained bradycardia

Answer 20

C: Initial parasympathetic discharge followed by a sustained sympathetic response

An initial parasympathetic discharge followed by a sustained sympathetic response is immediately seen after the induction of a seizure. Marked bradycardia with increased secretions can occur, which is then followed by hypertension and tachycardia. Patients scheduled for ECT are routinely given anticholinergic medication preoperatively.

Question 21

During emergent transtracheal jet ventilation using a 14 gauge catheter, generation of sufficient gas flow requires driving pressure of _______.

Answer 21

50 psi

After proper location of the catheter is confirmed by aspiration air, jet ventilation may be achieved with intermittent pulses of oxygen at 50 psi.

Question 22

Basal metabolic oxygen consumption in a 20 kg patient is approximately ___________.

Answer 22

95 mL/min

Basal metabolic oxygen consumption can be estimated using the following formula:

Question 23

The highest rate of systemic absorption of local anesthetic is seen with:

A: Epidural injection
B: Intercostal injection
C: Caudal injection
D: Brachial plexus injection

Answer 23

B: Intercostal injection

The rate of systemic absorption of local anesthetic is proportionate to the vascularity of the site of injection: intravenous > tracheal > intercostal > caudal > paracervical > epidural > brachial plexus > subcutaneous.

Question 24

Absolute contraindications to electroconvulsive therapy (ECT) include:

A: Congestive heart failure
B: Pregnancy
C: Myocardial infarction 5 months prior to therapy
D: Increased intracranial pressure

Answer 24

D. Increased ICP

Absolute contraindications to ECT include recent MI (usually < 3 months), recent stroke (< 1 month), intracranial mass, or increased ICP from any cause. Relative contraindications include angina, CHF, significant pulmonary disease, bone fractures, osteoporosis, pregnancy, glaucoma and retinal detachment.

Question 25

In the neuromuscular junction, acetylcholine receptor binding sites are found on the:

A: α-subunits
B: β-subunits
C: δ-subunits
D: ε -subunits

Answer 25

A: α-subunits

Each acetylcholine (ACh) receptor in the neuromuscular junction consists of 5 protein subunits. Only the α-subunits are capable of binding ACh molecules. If both binding sites are occupied, the channel briefly opens. The α-subunits are also the site of action of neuromuscular blockers.

Question 26

In the fetus, the percentage of cardiac output directed to the placenta is approximately:

A: 10%
B: 25%
C: 50%
D: 100%

Answer 26

C: 50%

In the fetus, the lungs receive little blood flow. The placenta receives nearly one-half of the fetal cardiac output and is responsible for respiratory gas exchange.

Question 27

The elimination half-life of intravenously administered oxytocin in the parturient is approximately:

A: 30 to 120 seconds
B: 3 to 5 minutes
C: 10 to 15 minutes
D: 20 to 30 minutes

Answer 27

B: 3 to 5 minutes

Both endogenous and intravenously administered oxytocin have short elimination half-lives of about 3 to 5 minutes. As a result, oxytocin must be administered as a continuous infusion for the induction of labor.

Question 28

A fresh E-cylinder of oxygen:

A:Contains more liters of gas than an E-cylinder of nitrous oxide
B: Contains about 90% liquid oxygen and 10% oxygen as a gas
C: Contains about 660 liters of oxygen when at sea level
D: Has a lower pressure than the pipeline oxygen supply

Answer 28

C. Contains about 660 liters of oxygen when at sea level

A fresh E-cylinder of oxygen contains about 660 liters of oxygen and is pressurized to 1900 psi.