c3. BASIC PRInciples B (76-150)

Question 0

77. After burns, the plasma to interstitial fluid shift occurs:
    a. in 1 to 2 hours
    b. during the first 24 hours
    c. during the first 48 hours
    d. during the first 72 hours

Answer 0

-c. during the first 48 hours

After 48 hours, capillary integrity returns to normal and colloid solutions will remain intravascular.

Question 1

76. The area of the autonomic nervous system concerned with baroreceptors is the:
    a. right atrium and right ventricle
    b. carotid sinus and aortic arch
    c. left atrium and left ventricle
    d. left ventricle and abdoinal aorta

Answer 1

-b. carotid sinus and aortic arch
receptors for pressure measurement in the body are located in the aortic arch and carotid sinuses with appropriate feedback mechanisms to cause changes when necessary

Question 4

78. Among the list of calcium salts, which one ionizes the most?
    a. calcium chloride
    b. calcium gluconate
    c. calcium oxalate
    d. calcium hydroxide

Answer 4

• a. calcium chloride
  It has long been believed that calcium chloride ionizes to a greater extent (3 x) than calcium gluconate; however recent studies refute this??

Question 5

79. The facial nerve performs all of the following except:
    a. supplies the muscles of facial expression
    b. conveys secretotor fibers to the lacrimal and salivary glands
    c. transmits taste fibers from the anterior two thirds of the tongue
    d. transmits taste fibers from the posterior one third of the tongue

Answer 5

-d. transmits taste fibers from the posterior one third of the tongue
the lingual and laryngeal branches of the glossopharyngeal nerve provide sensation from the posterior one third of the tongue and oral pharynx

Question 6

80. The initial dose of dantrolene for treating MH is:
    a. 1.5 mg/kg
    b. 2.5 mg/kg
    c. 10 mg/kg
    d. 20 mg/kg

Answer 6

-b. 2.5 mg/kg

The usual starting dose in the treatment of MH is 2.5 mg/kg, repeated as necessary up to 10 mg/kg.

Question 7

81. Identify the vital sign most detrimental in the patient with coronary artery disease:
    a. MAP decreases to 50 mmHg
    b. MAP increases to 120 mmHg
    c. heart rate increases
    d. preload increases

Answer 7

-c. heart rate increases
Tachycardia results in the greatest increase in the work of the heart, therefore the greatest potential for mismatch between supply and demand. *Also it causes a decreased filling time further decreasing supply to coronary vessels (tachycardia shortens diastole)

Question 8

82. coronary perfusion pressure is increased as a result of:
    a. increased diastolic pressure
    b. increased left ventricular diastolic pressure
    c. systolic hypertension
    d. tachycardia

Answer 8

-a. increased diastolic pressure
Because coronary perfusion occurs during diastole, increases in diastolic pressure result in an increase in coronary perfusion.

Question 9

83. which bellows is safer when there is a disconnect?
    a. ascending
    b. descending
    c. both are equally safe
    d. depends on the site of disconnect

Answer 9

-a. ascending
ascending bellows that are found in most modern anesthesia equipment is safer because a disconnect is more easily observed when the bellows do not ascend on cycling (with spont. bellows ascend on exhalation)

Question 10

84. What is the maximum amount of hetastarch that should be given to a patient?
    a. 10 mg/kg
    b. 20 mg/kg
    c. 10 ml/kg
    d. 20 ml/kg

Answer 10

-d. 20 ml/kg/day
Hetastarch has a long plasma life of 1.5 days and does not affect coagulation when used in recommended doses, which should be limited to no more than 20 ml/kg/day

Question 11

85. Which statement is incorrect regarding the aged patient?
    a. the elimination half-life of pancuronium is similar to that of a 30 year old
    b. the induction dose for thiopental is decreased
    c. the minimal alveolar concentration of halothane is decreased
    d. the hand to brain circulation time is greater than 15 seconds

Answer 11

-a.
Elimination half life of virtually all drugs is prolonged with increasing age. This includes the muscle relaxants, which last longer in elderly patients.

Question 12

86. the volume of distribution of drugs in the elderly is:
    a. increased for water soluble drugs
    b. decreased for lipid soluble drugs
    c. increased for lipid soluble drugs
    d. constant for both water and lipid soluble drugs

Answer 12

-c.
geriatric patients have a less well developed blood brain barrier in cell membranes. Therefore, drugs that are lipid soluble distribute more freeely resulting in a higher distribution volume

Question 13

87. Diffusion hypoxia is a phenomenon associated with rapid movement of which anesthetic agent from the circulation into the lungs producing a significant dilution of oxygen:
    a. halothane
    b. sevoflurane
    c. isoflurane
    d. nitrous oxide

Answer 13

-d. nitrous oxide

diffusion hypoxia occurs owing to the insolubility of nitrous oxide and the high concentrations administered

Question 14

88. The nonionized form of a local anesthetic is:
    a. water soluble
    b. lipid soluble
    c. unable to cross the placental barrier
    d. electrically charged

Answer 14

-b. lipid soluble
nonionized forms of all drugs will be lipid soluble because no charge is present to repel the molecule from lipid membranes.

Question 15

89. The rapidity and extent of diffusion of a local anesthetic to its site of action depends primarily on:
    a. pka of the drug
    b. concentration of drug injected
    c. lipid solubility
    d. all of the above

Answer 15

-d. all of the above
Local anesthetics must diffuse throught the lipid nerve membrane to reach their site of action. All of the listed factors will either increase lipid solubility or concentration in the nerve.

Question 16

90. It is important to monitor the right radial pulse during mediastinoscopy to detect:
    a. right carotid artery compression
    b. inominate artery compression
    c. right brachial artery compression
    d. ascending aorta compression

Answer 16

-b. inominate artery
Monitoring the right radial pulse will signal compression by the scope on the inominate (brachiocephalic) artery and allow for repositioning to ensure adequate circulation. Blood pressure should be monitorid in the left arm because of this potential compression.

Question 17

91. Autonomic hyperreflexia is rarely seen in cases of cord transection below:
    a. T5
    b. T10
    c. T12
    d. L2

Answer 17

-a. T5
Overactivity of the sympathetic nervous system is common with transection at T5 or above and is unusual with injuries below the T10 level.

Question 18

92. Sympathetic preganglionic cardiac accelerator nerve outflow is from which ganglia?
    a. C1-C4
    b. C7-T5
    c. T1-T5
    d. T5-T10

Answer 18

-c. T1-T5
Sympathetic innervation to the heart is mediated via sympathetic fibers arising from the cord at the level T1 through T5 (with T3, T4 & T5 having the greatest input).

Question 19

93. The superior laryngeal nerve provides _____ innervation to the larynx.
    a. sensory
    b. motor
    c. sensory and motor
    d. proprioceptive

Answer 19

-c. sensory and motor
The suerior laryngeal branch of the vagus divides into an external (motor) nerve and internal (sensory) laryngeal nerve that provides sensory supply to the larynx between the eipglottis and the vocal cords.

Question 20

94. Structurally, the larynx is composed of _____ (number) of cartilages.
    a. three
    b. five
    c. seven
    d. nine

Answer 20

-d. nine
The larynx is composed of 9 cartilages (3 single and 6 paired):
Single:
-thyroid
-cricoid
-epiglottic
Paired:
-aretynoid
-corniculate
-cuneiform

Question 21

95. Indirect acting sympathomimetic drugs exert their effect by:
    a. stimulating beta receptors
    b. stimulating alpha receptors
    c. causing catecholamine release
    d. blocking catecholamine release

Answer 21

-c. causing catecholamine release

Many sympathomimetic drugs act by causing endogenous release of catecholamines, which results in an adrenergic effect.

Question 22

96. Cardiac output in the parturient is greater at which point in pregnancy?
    a. 10-12 weeks gestation
    b. immediately postpartum
    c. 20 weeks gestation
    d. immediately after conception

Answer 22

-b. immediately postpartum
Cardiac output reaches a maximum immediately after delivery where it can be increased as much as 60% of normal. It returns to normal within 2 weeks of delivery.

Question 23

97. The vasopressor of choice for the parturient after SAB administration is:
    a. phenylephrine
    b. ephedrine
    c. epinephrine
    d. methoxamine

Answer 23

-b. ephedrine
Ephedrine preserves uterine blood flow to a greater extent than either pure alpha-receptor vasopressors (phenylephrine) or epinephrine. (old school thought process; phenylephrine is used more and more).

Question 24

98. An absolute contraindication to the adminiistration of heparin for cardiopulmonary bypass is:
    a. carotid disease
    b. recent CVI
    c. increased antithrombin III activity
    d. previous streptokinase therapy

Answer 24

-c. increased antithrombin III activity
Heparin antithrombin III and serine proteases combine to produce the anticoagulant effect. Elevated antithrombin III would affect coagulation and heparin should be avoided.

Question 25

99. Elderly patients may become hypertensive and not exhibit any compensetory changes in heart rate because of:
    a. diminished activity of carotid sinus reflex responses
    b. reduced sympathetic afferent traffic to the medulla
    c. decreased responsiveness of nervous system mediated compensatory mechanisms
    d. increased parasympathetic efferent traffic to the sinus node.

Answer 25

-c. decreased responsiveness of nervous system mediated compensatory mechanisms
With age there is a decreased responsiveness to the usual compensatory mechanisms. This occurs in the central nervous systems cardiovascular control centers which send the inputs by means of the autonomic nervous system and alpha, beta and muscarenic receptors.

Question 26

100. What are the cardiovascular effects of positive end-expiratory pressure (peep)? a. decreased cardiac output b. stabilized pulmonary blood flow c. augment venous return d. increased lymphatic flow

Answer 26

-a. decreased cardiac output The decrease in cardiac output produced by PEEP is due to interference with venous return and a leftward displacement of the heart that restricts filling of the left ventricle.

Question 27

101. Correct application of Sellick's maneuvre includes: a. gentle pressure applied over the cricothyroid membrane b. using the index finger to apply pressure over the thyroid c. maintaining cricoid pressure during positive pressure ventilation d. pinching the cricoid cartilage between the thumb and index finger

Answer 27

-c. maintaining cricoid pressure during positive pressure ventilation Moderate positive pressure ventilation does not increase air entry into the stomach as long as the airway remains patent.

Question 28

102. Which of the following drugs would be contraindicated in the patient with parkinson's disease? a. droperidol b. thiopental c. fentanyl d. midazolam

Answer 28

-a. droperidol (inapsine) Droperidol has an ANTI-DOPAMINE effect; therefore it is contraindicated in patients with parkinson's disease because extrapyrimidal side effects can occur.

Question 29

103. What are the cardiovascular effects of cocaine? a. bradycardia b. reduced vascular resistance c. cardiac dysrhythmias d. decreased cardiac output

Answer 29

-c. cardiac dysrhythmias | because of the reuptake of catecholamines, cocaine may produce multiple cardiac dysrhythmias

Question 30

104. The most important mechanism for the termination of action of norepinephrine is: a. uptake into the preganglionic nerve terminals b. reuptake into postganglionic nerve endings c. metabolism by catechol-o-methyl transferase (comt) d. competition of increasing acethycholine

Answer 30

-b. reuptake into postganglionic nerve endings like other neurotransmitters, the main effect of norepinephrine is terminated by active reuptake and transport into the nerve terminal.

Question 31

105. what are the effects of cocaine on the centran nervous system: a. increased seizure threshold b. central hypothermic activity c. stimulation then depression d. strong antiemetic effects

Answer 31

-c. stimulation then depression with chronic therapy, catecholamine levels decrease and the initial stimulation is then followed by a central nervous system depression and fatigue. (??decreased seizure threshold and hyperthermic activity??)

Question 32

106. Clonidine is a: a. adrenergic neuron blocker b. central alpha 2 receptor agonist c. direct acting arteriolar vasodilator d. direct acting vasodilator

Answer 32

-b. central alpha 2 receptor agonist | by stimulating central alpha 2 receptors, produces a vasodepressor and sedative effect

Question 33

107. which physiological derangement will result in slower metabolism of ester local anesthetics a. acute renal failure b. atypical plasma cholinesterase c. hyperkalemia d. diabetes insipidis

Answer 33

-b. atypical plasma cholinesterase ester local anesthetic metabolism is catalyzed by cholinesterase, therefore patients with atypical genotypes will have prolonged metabolism.

Question 34

108. Duchene muscular dystrophy has been implicated with what drug in a life threatening side effects? a. verapamil b. cyclosporine c. esmolol d. succinylcholine

Answer 34

-d. sux several recent reports of sudden cardiac arrest after administration of succinylcholine to patients with undiagnosed Duchenne muscular dystrophy has led to warning in children younger than 12 yrs old.

Question 35

109. A normal (average) dibucaine number is: a. 50 b. 60 c. 80 d. 100

Answer 35

-c. 80 Dibucaine inhibits normal cholinesterase. The dibucaine number reflects the amount of inhibition that in the average person equals approximately 80%.

Question 36

110. Rebound hypertension after cessation of sodium nitroprusside drip results from: a. vasoconstriction b. renin release c. central nervous system stimulation d. catecholamine release

Answer 36

-b. renin release After nitroprusside drip is discontinued, there is a rebound release of renin, which results in a period of rebound hypertension.

Question 37

111. The oxygen pressure from piped in systems leading to anesthesia machines should be in the range of: a. 40 psi b. 50 psi c. 60 psi d. 70 psi

Answer 37

-b. 50 psi Hospital piping systems provide gas to the machine at approximately 50 psi, which is the normal working pressure of most machines

Question 38

112. Pressure sensor shut off valves will be activated when the pressure of oxygen falls below: a. 15 psi b. 25 psi c. 35 psi d. 40 psi

Answer 38

-b. 25 psi The pressure sensor shut off valve decreases the supply of nitrous oxide if the oxygen supply pressure falls below approximately 25 psi

Question 39

113. The statement that the amount of gas dissolving in a liquid is proportional to the partial pressure of the gas defines: a. charles' law b. boyle's law c. graham's law d. henry's law

Answer 39

-d. henry's law Henry's law states that the concentration of any gas in solution is proportional to the partial pressure of that gas (at a constant temp). Henry=dissolved amount is equal to partial pressure at constant temp

Question 40

114. (MAP-CVP) X 80/CO measures: a. pulmonary vascular resistance b. MAP and CVP pre heart beat c. SVR d. systemic refraction of cardiac output

Answer 40

-c. SVR total SVR is calculated from hemodynamic variables derived with a pulmonary artery catheter. the normal systemic vascular resistance is 1200 to 1500 dynes/sec/cm-5

Question 41

115. One of the greatest advantages to a non breathing system for children is: a. loss of heat and humidity b. low flow rates c minimal resistance d. maximal dead space

Answer 41

-c. minimal resistance nonbreathng systems are used for children primarily because they offer little resistance to breathing and will not as easily cause fatigue in a child's respiration.

Question 42

116. clamping of the abdominal aorta during aneurysm surgery is followed by: a. loss of blood pressure in the right arm b. immediate drop in systolic blood pressure c. no change d. immediate rise in systolic blood pressure

Answer 42

-d. immediate rise in systolic bp clamping of the aorta causes an acute increase in left ventricular afterload which can result in ischemia, failure, and severe hypertension. Use of vasodilators can attenuate (solve) this problem

Question 43

117. the principal catalyst for carbon dioxide absorption in soda lime and baralyme is: a. magnesium hydroxide b. postasium hydroxide c. sodium hydroxide d. calcium hydroxide

Answer 43

-c. sodium hydroxide is a catalyst for carbon dioxide absorption in soda lime, although both substances contain more calcium hydroxide than sodium hydroxide

Question 44

118. current F-29 standards mandate the use of ventilator bellows that: a. descend on inspiration b. ascend on inspiration c. descend on expiration d. ascend on expiration

Answer 44

-d. ascend on expiration ventilators whose bellows ascend expiration have been deemed the safest regarding disconnects and are now in use on all anesthesia equipment

Question 45

119. Which ventilator mode allows spontaneous respiratory effort while administering a pre set tidal volume at a specific interval. a. assisted- controlled ventilation b. synchronized intermittent mandatory ventilation c. controlled ventilation d. mandatory minute ventilation

Answer 45

-b. synchronized intermittent mandatory ventilation | SIMV allows the patient to initiate a breath but ensures that he or she receives an adequate tidal volume

Question 46

120. Diaphoresis under general anesthesia may indicate: a. hypercapnia b. deep anesthesia c. hypoxia d. hypocarbia

Answer 46

-a. hypercapnia high carbon dioxide levels result in tachycardia, restlessness and diaphoresis. Fortunately with improved monitorind, this has become less of a propblem

Question 47

121. Which of the following nondeporalizing muscle relaxants has the most rapid onset. a. succinylcholine b. vecuronium c. rocuronium d. pancuronium

Answer 47

-c. rocuronium in equivalent doses, rocuronium exhibits the fastest onset for intubating conditions among the nondepolarizing muscle relaxants

Question 48

122. During a pneumonectomy, the main bronchus is clamped. What is the most important physiologic finding? a. decreased tidal volume b. increased CO2 c. decreased PAo2 d. increased peak inspiratory pressure

Answer 48

-d. increased pip Airway resistance increases greatly when the bronchus in the diseased lung is clamped. Adjustments in respiration to ensure adequate oxygenation and CO2 removal are necessary.

Question 49

123. Which of the following lab values would not be expected in a patient with chronic renal disease? a. BUN of 52 b. creatnine of 1.2 c. ph: 7.41 d. hemogolbin: 9.2

Answer 49

-c. ph: 7.41 patients with chronic renal failure do not excrete non volatile acids; which results in high anion gap metabolic acidosis

Question 50

124. an agent is removed faster from the central compartment if: a. half life is short with small volume of distribution b. half life is short with large volume of distribution c. half life is long with small volume of distribution d. half life is long with large volume of distribution

Answer 50

-a. short half life with small vD a small volume of distribution means the drug is primarily the blood stream and, with a short half life, this would make it easily removed from the body

Question 51

125. The concentration of which of the following differs greatest in the trachea from ambient air? a. oxygen b. carbon dioxide c. nitrogen d. water

Answer 51

-d. water one of the main functions of the airway is to increase the humidity of gases as they are breathed; therefore the water vapor increases as gases are drawn into the lungs

Question 52

126. In banked blood there is an excess of all of the following except: a. ammonia b. hydrogen ions c. 2,3- diphosphoglycerate d. plasma potassium

Answer 52

-a. ammonia ammonia increases in the blood in intact humans when there is liver damage and is released as urea when synthesized. In banked blood, ammonia levels stay constant and are not affected during transfusion...note...however 2,3-dpg levels in banked blood ARE LOW!!

Question 53

127. If an awake patient is placed in the lateral position, there will be: a. decreased perfusion to the down lung b. decreased ventilation to the down lung c. increased? ventilation to the top lung d. increased perfusion to the top lung

Answer 53

-b. decreased ventilation to the down lung Spontaneous ventilation may partially compensate for the compression on the dependent hemithorax; however, there is still a slight decrease in the ventilatory capacity in the down lung.

Question 54

128. The following finding are symptomatic in pyloric stenosis except: a. metabolic acidosis b. hypochloremia c. dehydration d. hypokalemia

Answer 54

-a. metabolic acidosis Persistent vomiting in a patient with pyloric stenosis depletes sodium, potassium, chloride and hydrogen ions causing metabolic alkalosis

Question 55

129. Which of the following represents the best criterion for extubation after effective reversal of nondepolarizing muscle relaxation. a. return of reflexes b. sustained tetanus c. tidal volume of 5 ml/kg d. head lift sustained for 5 seconds

Answer 55

-d. head lift sustained for 5 seconds although all of the answers are important, sustaining headlift for 5 secnds appears to correlate with muscle strength to a greater degree than the other parameters.

Question 56

130. The occupational safety and health administration defines acceptable limits of pollutants in the OR as: a. halothane 25 parts per million (ppm) b. halothane 50 ppm c. nitrous oxide 2 ppm d. nitrous oxide 25 ppm

Answer 56

-d. NO2 25 ppm Recomendations for nitrous oxide are based on studies by Bruce and colleagues, who noted after exposure to 25 ppm of nitrous oxide that no impairment of psychomotor tests was present

Question 57

131. Which of the following is of concern when anesthetizing an acromegalic patient? a. hypercalcemia b. laryngeal edema c. probable hiatal and diaphragmatic hernia d. altered airway structure and landmarks

Answer 57

-d. altered airway structure and landmarks distortion of the facial anatomy and uper airway, including enlarged tongue and epiglottis and thickened vocal cords is common with this disorder.

Question 58

132. The department of transportation mandates that gas cylinders be checked at what interval? a. each refill b. semi-annually c. annually d. every 5 years

Answer 58

-d. every 5 years to ensure the safety of medical cylinders, inspection must be completed every 5 years. This has become a standard in the US

Question 59

133. Which level of humidity is recommended to prevent explosion hazard in the operative suite? a. 50-60% relative humidity b. 50-60% absolute humidity c. greater than 60% absolute humidity d. 100% relative humidity

Answer 59

-a. 50-60% relative humidity | static dischared, which are a source of ignition are much less likely if the relative humidity is at least 50%

Question 60

134. after extubation after parathyroidectomy, your patient experiences mild stridor and significant hoarseness. You suspect: a. hematoma formation b. superior laryngeal nerve injury c. laryngeal bruising d. recurrent laryngeal nerve injury

Answer 60

-d. recurrent laryngeal nerve injury | a diagnosis of stridor hoarseness (unilateral=aphonia) is an indication of recurrent laryngeal nerve damage

Question 61

135. current research suggests that the pathologic process underlying the clinical syndrome of malignant hyperthermia may be: a. interference with sodium-potassium/ATPase pump b. sympathetic nervous system hypersensitivity c. impaired intracellular control of calcium d. blockade of intracellular sodium/calcium pump

Answer 61

-c. impaired intracellular control of calcium malignant hyperthermia results from an increase in myoplasmic calcium. The ryanodine receptor may be involved because control of calcium by this receptor is prominant in muscle cells.

Question 62

136. Which of the following factors is most important when planning anesthesia for the patient undergoing portacaval shunt? a. distended ascitic abdomen b. decreased levelof consciousness c. decreased cerebral blood flow d. anemia

Answer 62

-a. distended ascitic abdomen a grossly distended abdomen makes the patient at very high risk for aspiration and desaturation in the airway is difficult, as well as for hypotension from decreased venous return.

Question 63

137. Drug interations with phenytoin and warfarin include: a. enhanced biotransformation of warfarin and reduced bleeding time b. increased sedation and prolonged anticoagulation activity c. reduced biotransformation of warfarin and increased bleeding time d. increased renal excretion of phenytoin with a reduced seizure threshold

Answer 63

-b. increased sedation and prolonged anticoagulation activity Increased action of both phenytoin and warfarin would be expected because the interaction involves the high protein binding and displacement of the drugs, increasing free concentration.

Question 64

138. Drug interactions with clonidine and propanolol would cause: a. hypertension b. hypotension c. tachycardia d. hypoglycemia

Answer 64

-b. hypotension both clonidine and propanolol produce a vaso-depressor response, so when they are given together the possiblilty of hypotension is greatly increased.

Question 65

139. Identify the mechanism most likely to explain the drug interactions seen with cimetidine and many classes of drugs. a. alteration of gastric acidity and enhanced drug absorption b. competitive inhibition in the distal tubule with altered excretion c. great reduction in hepatic blood flow and drug clearance d. inhibition of the microsomal cytochrome p450 system in the liver

Answer 65

-d. inhibition of microsomal cytochrome p450 system in the liver cimetidine is famous for its ability to inhibit drug metabolizing enzymes in the liver, resulting in the decreased metabolism of other drugs relying on the liver for biotransformation.

Question 66

140. what is the effect of verapamil on blood coagulation? a. prolonged prothrombin time b. shortened partial thromboplastin time c. inhibition of factors II and VII d. increased bleeding time

Answer 66

-d. increased bleeding time | High doses of calcium channel blockers have been reported to increase bleeding by reducing calcium coagulant ability

Question 67

141. In shock, what unique feature of dopamine makes it a drug of choice? a. renal tissue blood flow can be increased b. myocardial contractility is usually decreased c. myocardial oxygen consumption is decreased d. peripheral vascular resistance is decreased

Answer 67

-a. renal tissue blood flow can be increased dopamine stimulates dopamine receptors in renal arteries resulting in vasodilation, increased blood flow, and increased GFR

Question 68

142. The treatment for extrapyramidal effects associated with droperidol is: a. midazolam b. diphenhydramine c. cimetidine d. morphine

Answer 68

-b. diphenhydramine extrapyramidal side effects usually require no treatment; however, if they are extreme, anticholinergic therapy with diphenhydramine may help relieve these symptoms.

Question 69

143. Treatment of cyanide toxicity includes all of the following except: a. amyl nitrate b. sodium nitrate c. sodium thiosulfate d. sodium thiocyanate

Answer 69

-d. sodium thiocyanate sodium thiocyanate is the end product of metabolism of cyanide by thiosulfate. Thiocyanate is then excreted in the kidney as a nontoxic byproduct.

Question 70

144. The cascade of events occuring with cyanide toxicity are due to: a. the development of metabolic acidosis b. a loss of buffering capacity c. decreased ability of molecular oxygen d. inablility of the tissues to utilize oxygen

Answer 70

-d. inability of the tissuess to utilize oxygen | cyanide poisoning represents histotoxic hypoxia, which is the inabilty of the cell to utilize oxygen.

Question 71

145. Which of the following drugs has been shown to directly antagonize benzodiazepine induced sedation? a. naloxone b. naltrexone c. doxapram d. aminophylline

Answer 71

-d. aminophylline Aminophylline has been shown to decrease sedation from benzodiazepines possibly by means of an effect on adenosine receptors

Question 72

146. The relative affinity of an anesthetic and how it partitions itself in the body is implied in which of the following? a. concentration effect b. second gas effect c. blood solubility d. pressure gradient

Answer 72

-c. blood solubility (bgsc) | blood gas solubility partition coefficient is a measure of how an anesthetic compartmentalizes itself in the body

Question 73

147. Flexation of the intubated neonate's head: a. may cause endobronchial intubation b. may cause inadvertent extubation c. may cause laryngospasm d. may expose the glottic opening

Answer 73

-a. may cause endobronchial intubation | flexion of a child's head may advence the tube more deeply into the chest, resulting in endobronchial intubation

Question 74

148. Which of the following class of drugs lowers intraocular pressure? a. alpha agonist b. alpha blockers c. beta agonist d. beta blockers

Answer 74

-d. beta blockers Beta-receptor blocking drugs are comonly given to people with glaucoma. These agents appear to decrease synthesis of aqueous humor, thus reducing pressure in the eye.

Question 75

149. Which of the following is not a pathophysiologic change in toxemia of pregnancy? a. decrease GFR b. proteinuria c. dehydration d. hypertension

Answer 75

-d. hypertension | hypertension is the hallmark characteristic of theis pregnancy induced syndrome also known as preeclampsia

Question 76

150. In an upright normal subject, the ventilation per unit volume is greatest in: a. lung bases b. lung apices c. posterior portions of the lung d. middle portions of the lung

Answer 76

-b. lung apices | In the upright position, the greatest amount of air exchange occurs in the upper airway due to gravity