NBCRNA CRNA Exam Questions

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61.

All the following are physiological effects of acidemia except:

  • Increased cardiac contractility

  • Decreased peripheral vascular resistance

  • Decreased threshold for ventricular fibrillation

  • Progressive hypotension

Correct answer: Increased cardiac contractility

With acidemia, direct depressant effects of hydrogen are seen. Direct myocardial and smooth muscle depression reduces cardiac contractility and peripheral vascular resistance, resulting in progressive hypotension.

Both cardiac and vascular smooth muscle become less responsive to endogenous and exogenous catecholamines, and the threshold for ventricular fibrillation is decreased.

62.

Which complications are a patient with diabetes mellitus more likely to experience following surgery? (Select 3.)

  • Cardiac ischemia

  • Sepsis

  • Wound infection

  • Pancreatitis

  • Laryngospasms 

Diabetes mellitus increases the risk of hyperglycemia in the postoperative period. Hyperglycemia is associated with cardiovascular events and with an increased risk of infectious processes, such as wound infection and sepsis. Pancreatitis and laryngospasms are not common postoperative complications caused by hyperglycemia.

63.

Which of the following terms used in research describes the most frequently occurring number in the sample?

  • Mode

  • Mean

  • Median

  • Variance

Correct answer: Mode

The mode is the value that occurs most frequently in a sample.

The mean is the mathematical average of the sample. The median is the point at which half the measurements in the sample are above and half the measurements are below. Variance is the square of the sum of all the deviations divided by the number of scores.

64.

Which of the following is the greatest concern with the abrupt discontinuation of clonidine?

  • Hypertension

  • Intractable pain

  • Cardiac dysrhythmias 

  • Tachycardia

Correct answer: Hypertension

Clonidine is an alpha2-adrenergic agonist and is used to treat hypertension. Abrupt discontinuation of clonidine can cause a significant risk of rebound hypertension. Intractable pain, cardiac dysrhythmias, and tachycardia are all not common concerns with the abrupt discontinuation of clonidine.

65.

A three-year-old patient is undergoing an MRI. Which of the following should the anesthesia provider anticipate will be most likely?

  • The patient will require general anesthesia

  • The patient will require moderate sedation

  • The patient will only require an anxiolytic 

  • The patient will only require anesthesia care if a significant comorbidity is present 

Correct answer: The patient will require general anesthesia

Pediatric patients undergoing unfamiliar imaging procedures that require remaining still for a prolonged period of time will typically require general anesthesia. Moderate sedation or an anxiolytic are unlikely to be sufficient in these situations. Significant comorbidities alter anesthetic considerations and the care that will be necessary; however, the patient will still require anesthesia care even if no comorbidities are present.

66.

All the following statements are true about aging and the nervous system except:

  • Elderly patients demonstrate a decrease in sympathetic outflow

  • Elderly patients demonstrate decreased baroreceptor sensitivity

  • Gray matter is more affected by atrophy due to aging than white matter

  • Elderly patients have a compensatory increase in cerebral spinal fluid due to decreased brain mass

Correct answer: Elderly patients demonstrate a decrease in sympathetic outflow

Elderly patients demonstrate a decrease in parasympathetic outflow and an increase in sympathetic outflow. These changes lead to compromise in thermoregulation, decreased baroreceptor sensitivity, reductions in cerebral blood flow, and decreased neurotransmitter production.

Gray matter is more affected than white matter by atrophy, and there is a compensatory increase in cerebral spinal fluid.

67.

In a Mapleson D system, what is the minimum amount of fresh gas flow needed to prevent rebreathing?

  • 2 to 3 times minute ventilation

  • Equal to minute ventilation

  • 50% of total minute ventilation

  • 4 times minute ventilation

Correct answer: 2 to 3 times minute ventilation

Mapleson D and F circuits offer very low resistance to breathing and can be used for patients of almost any age, from premature infants to adults. The fresh gas flow required to prevent rebreathing is two to three times minute ventilation.

68.

The CRNA who is providing anesthesia for a 75-year-old patient undergoing a total hip arthroplasty notices an abrupt decrease in the patient's end-tidal carbon dioxide concentration after the femoral prosthesis has been secured. This physiologic change is indicative of which of the following?

  • Bone cement implantation syndrome

  • Methyl methacrylate syndrome

  • Press-fit implantation syndrome

  • Fat emboli syndrome

Correct answer: Bone cement implantation syndrome

In older patients who undergo total hip arthroplasty (THA), typically a bonding agent or cement is used to fix the joint prosthetic in place once the diseased joint has been removed. The bonding agent methyl methacrylate (MMA) is most commonly used for fixing the joint during THA. It is applied to the femoral canal after it has been reamed out and cleaned in preparation for the prosthesis. Bone cement implantation syndrome (BCIS) may occur as a result of the use of MMA during THA. For the sleeping, anesthetized patient, the first sign of BCIS may be an abrupt decrease in the end-tidal carbon dioxide concentration. Other symptoms may include arrhythmias, hypotension, hypoxia, or loss of consciousness in the awake, regionally-anesthetized patient. An increase in pulmonary vascular resistance or even cardiac arrest may also occur.

69.

Which of the following statements is true about patients on long-term angiotensin-converting enzyme inhibitor therapy who undergo general surgery?

  • They are at risk for intraoperative hypotension due to decreased cardiac output

  • They are at risk for intraoperative hypertension

  • The renin-angiotensin-aldosterone system is the only system intact to support blood pressure

  • The angiotensin-converting enzyme inhibitor decreases the risk of prolonged hypotension by blunting the renin-angiotensin-aldosterone system

Correct answer: They are at risk for intraoperative hypotension due to decreased cardiac output

Surgical patients who are on long-term Angiotensin-Converting Enzyme (ACE) inhibitor therapy are at risk for prolonged hypotension during general anesthesia due to the increased venoconstrictive effects of angiotensin on the capacitance vessels, which decreases cardiac output.

Patients on long-term ACE inhibitor therapy are at risk for intraoperative hypotension, rather than hypertension. The vasopressin system, rather than the renin-angiotensin-aldosterone system, is the only system intact to support blood pressure. The ACE inhibitor increases, rather than decreases, the risk for prolonged hypotension because it may cause blunting of the renin-angiotensin-aldosterone system.

70.

What is the purpose of an oxygen failure safety device on the modern anesthesia workstation?

  • To prevent administration of nitrous oxide or other gases when the supply of oxygen fails

  • To prevent simultaneous administration of more than one volatile agent

  • To prevent incorrect cylinder attachments

  • To allow for rapid refilling of the breathing circuit

Correct answer: To prevent administration of nitrous oxide or other gases when the supply of oxygen fails

Most modern anesthesia workstations use a proportioning safety device instead of a threshold shut-off valve. These devices, called either an oxygen failure protection device or a balance regulator, proportionately reduce the pressure of nitrous oxide and other gases, except for air. They completely shut off nitrous oxide and other gas flow only below a set minimum oxygen pressure.

The vaporizer interlock device prevents simultaneous administration of more than one volatile agent. The pin index safety system prevents incorrect cylinder attachments. An oxygen flush mechanism that does not pass through vaporizers allows for rapid refilling of the breathing circuit.

71.

Which of the following statements best describes unfractionated heparin's mechanism of action?

  • Unfractionated heparin binds to antithrombin and causes a change that greatly increases antithrombin's inhibitory activity

  • Unfractionated heparin competes with vitamin K for the carboxylation binding sites, leading to the depletion of factors II, VII, IX, X, protein C, and protein S

  • Unfractionated heparin decreases the activity of a second native antithrombin, heparin cofactor II

  • Unfractionated heparin inhibits both unbound and fibrin-bound thrombin

Correct answer: Unfractionated heparin binds to antithrombin and causes a change that greatly increases antithrombin's inhibitory activity

Unfractionated heparin is used widely for anticoagulation in vascular surgery and in procedures requiring cardiopulmonary bypass. It inhibits coagulation principally through its interaction with antithrombin.

Warfarin, not unfractionated heparin, competes with vitamin K for the carboxylation binding sites, leading to the depletion of factors II, VII, IX, X, protein C, and protein S. Unfractionated heparin increases (not decreases) the activity of a second native antithrombin, heparin cofactor II. Direct thrombin inhibitors, (not unfractionated heparin) inhibit both unbound and fibrin-bound thrombin.

72.

How is a 25% reduction in hepatic blood flow typically compensated?

  • Modulation of hepatic artery tone

  • A 25% reduction in hepatic blood flow cannot be compensated

  • Modulation of portal vein tone

  • Modulation of systemic vascular tone

Correct answer: Modulation of hepatic artery tone

Modulation of hepatic artery tone is the primary means of compensating for the reduction in hepatic blood flow and can compensate for reductions in hepatic blood flow of up to 50%. Portal vein flow is not regulated. Modulation of systemic vascular tone is not the primary means of regulating hepatic blood flow. 

73.

The CRNA is performing a check of the anesthesia gas delivery system and knows that within the United States (US), nitrous oxide cylinders and pipeline demarcations are designated by the use of which of the following colors?

  • Blue

  • Yellow

  • Green 

  • White

Correct answer: Blue

The CRNA may be responsible for the delivery of anesthetic gases through the use of either gas cylinders or gas pipelines. Both internationally and within the United States (US), color coding is used to assist in the identification of specific gases. Within the US, nitrous oxide is demarcated by the color blue, while green is used to indicate an oxygen cylinder or pipeline, and air is designated by use of the color yellow. White is used internationally to indicate oxygen or air, dependent upon the country in which the gas is being used.

74.

All the following statements are true related to the physiological changes associated with aging except:

  • Creatinine clearance declines and serum creatinine level increases with age

  • By age 80, the number of functioning glomeruli is reduced by 50%

  • Mean arterial oxygen tension decreases from 95 mmHg at age 20 to less than 70mm Hg at age 80

  • Basal metabolic rate declines by 1% each year after the age of 30

Correct answer: Creatinine clearance declines and serum creatinine level increases with age

Creatinine clearance declines with age; however, serum creatinine level frequently remains within normal limits due to less skeletal muscle mass and less production of creatinine.

By age 80, renal tissue atrophy results in the number of functioning glomeruli being reduced by half. Mean arterial oxygen tension decreases from 95 mmHg at age 20 to less than 70 mmHg at age 80. Basal metabolic rate decreases by 1% each year after the age of 30.

75.

Where are complex dental surgical procedures most likely to be performed?

  • An office setting

  • Ambulatory surgery center

  • Operating room

  • Dedicated dental OR suites

Correct answer: An office setting

Complex dental surgical procedures will generally be performed in an office-based setting, even given their complexity. Ambulatory surgery centers or operating rooms would not generally be used for dental surgical procedures unless other facial structures were also involved. Dedicated dental OR suites are not a common surgical setting.

76.

Which of the following are principles of damage control resuscitation? (Select 3.)

  • Early use of hemostatic products

  • Stopping bleeding early

  • Permissive hypotension

  • Maximizing crystalloid use

  • Maximizing colloid use

The principles of damage control resuscitation (DCR) include stopping bleeding early, permissive hypotension, minimizing the use of crystalloids and colloids, and the early use of blood products.

77.

Which of the following are common causes of chronic pain in the elderly? (Select 3.)

  • Degenerative disease processes

  • Cancer

  • Neuropathy

  • Normal aging

  • Abuse-related trauma

Common causes of chronic pain in the elderly include degenerative disease processes, cancer, and neuropathy. Abuse-related trauma is not common in the elderly. However, all elderly patients should be screened for abuse. Normal aging does not cause chronic pain and pain is not part of the aging process.

78.

Which of the following effects results from H1 receptor stimulation? (Select 2.)

  • Increased capillary permeability 

  • Intestinal contraction

  • Bronchodilation

  • Positive inotropic effects 

  • Increased gastric acid production

Histamine receptors include H1 receptors and H2 receptors. Increased capillary permeability, intestinal contraction, and bronchoconstriction are all results of H1 receptor stimulation. H2 receptor stimulation results in positive inotropic effects and increased gastric acid production.

79.

A laboring patient who has an epidural in place is being moved to the operating suite for an emergency Cesarean section due to fetal distress. Which of the following anesthetic drugs used for epidural anesthesia in this scenario is most likely to decrease the effectiveness of epidural morphine administered after the Cesarean has been completed?

  • 2-chloroprocaine

  • 2% lidocaine

  • Ropivacaine

  • Bupivacaine-sufentanil

Correct answer: 2-chloroprocaine

The use of 2-chloroprocaine in obstetric anesthesia is essentially limited to its administration to laboring women who require emergency Cesarean section, and who have an epidural already in place. The anesthetic 2-chloroprocaine is rapidly metabolized, with only minimal amounts reaching the placenta. The administration of 2-chloroprocaine as a regional epidural anesthetic has been shown to decrease the effectiveness of doses of morphine that are administered after the close of the surgical case.

80.

Which of the following patients is at risk for increased bleeding as a result of factor VIII deficiency?

  • Patient with a history of hemophilia A

  • Patient with a history of Christmas disease

  • Patient with a history of hemophilia B

  • Patient with a history of Rosenthal disease (hemophilia C)

Correct answer: Patient with a history of hemophilia A

Within the United States, millions of people are affected by bleeding disorders. The more common of these disorders include hemophilia and von Willebrand disease, as well as other factor deficiencies. The hemophilias are X-linked recessive disorders, affecting males more often than females, and typically result in unforeseeable bleeding patterns. Hemophilia A results from a deficiency of factor VIII, while hemophilia B (also called Christmas disease) results from a deficiency of factor IX. 

Rosenthal disease (also called hemophilia C) is an autosomal recessive disorder often affecting the Ashkenazi Jewish and Basque populations more heavily. It is characterized by a prolongation of the aPTT. Von Willebrand disease may be inherited or acquired and may demonstrate various characteristics dependent upon the subtype of the disease.