Flashcards in c3. BASIC PRInciples C (151-224) Deck (74):
151. A patient develops bronchospasm under anesthesia that is not relieved by deepening levels. The next intervention may be:
a. administer a beta blocker
b. give calcium channel blocker
c. give a beta 2 agonist
d. administer iv steroids
-c. give a beta 2 agonist
administering a bronchodilating beta 2 agonist by means of inhalation or IV is the most effective tx of bronchospasm
152. Which of the following is true regarding ventilation and perfusion in the lateral position in the anesthetized, closed-chest patient?
a. the non depenednt lung is better perfused
b. the dependent lung is better ventilated
c. the non dependent lung is better ventilated
d. the dependent lung has less deadspace
-c. the non dependent lung is better ventilated
In the lateral position, the up lung is better ventilated owing to decreased compression of the chest wall as compared to the down lung
153. During muscle contraction, calcium combines with:
d. myofibril C
calcium allows actin fibers to react with myosin fibers, thus shortening the muscle fibers
154. A heat producing mechanism is thought to exist in what tissue known to play an important role in hibernating animals:
b. brown adipose
d. all of the above
-b. brown adipose
to maintain body temp, neonates create heat by metabolizing brown fat, crying and moving vigorously, but unlike adults they rarely shiver (brown fat thermogenesis)
155. Which of the following is usually not seen in patients with pyloric stenosis?
persistent vomiting that occurs with this syndrome results in inadequate hydration and hypovolemia (with electrolyte disturbances)
156. Theraputic magnesium levels for the treatment of preeclampsia are:
a. 1-2 meq/L
b. 4-6 meq/L
c. 8-10 meq/L
d. 20-25 meq/L
b. -4-6 meq/L
Theraputic magnesium levels are maintained to treat hyperreflexia and provent convulsions until delivery of the fetus and the placenta is possible
157. A significant incidence of cardiotoxicity is seen following the use of:
a. 3% chloroprocaine
b. 4% cocaine
c. 0.5% mepivacaine
d. 0.75% bupivacaine
-d. 0.75% bupivacaine
Use of high concentrations of bupivacaine results in initial cardiac arrest after systemic absorption rather than the expected neurotoxicity
158. The last structure the needle pass through in epidural anesthesia is the:
a. ligamentum flavum
b. dura mater
c. supraspinous ligament
d. arachnoid mater
-a. ligamentum flavum
with the midline approach, the needle passes through the supraspinous, interspinous, and ligamentum flavum to reach the epidural space
159. a postpartum patient who develops an inverted uterus with hemorrhage should be treated with what first?
b. 100% oxygen
c. halothane by mask
d. rapid sequence induction with ketamine
ensuring proper oxygenation is essential therapy in any hemorrhagic emergency
160. Which of the following intravenous solutions whould be avoided in the neurosurgical patient?
a. balanced salt solution
b. dextrose and water
c. lactated ringer's solution
d. normal saline
-b. dextrose and water
Dextrose and water solutions should not be used in neurosurgical patients because of the tendency for them to produce cerebral edema and alter glucose metabolism in the brain
161. Myocardial oxygen demand is decreased by:
b. decreased preload
c. increased afterload
d. increaed contractility
b. decreased preload
decreasing preload with vasodilators reduces venous return and the amount of work the heart must do to eject returning blood flow
162. myocardial oxygen consumption is most closely associated with:
a. heart rate
b. blood viscosity
c. cardiac output
d. stroke volume
-a. heart rate
increases in heart rate produce the greatest increase in cardiac work and must be avoided in patients with ischemic heart disease and congestive heart failure to prevent cardiac decompensation
163. cardiovascular changes that occur with advancing age are most typically associated with:
a. decreased blood pressure
b. decreased cardiac reserve
c. decreased heart rate
d. increased cardiac output
-b. decreased cardiac reserve
diminished cardiac reserve in many elderly patients may be seen as exaggerated drops in blood pressure during induction of anesthesia
164. Which of the following is a determinant of myocardial oxygen supply?
a. blood oxygen content
d. heart rate
-a. blood oxygen content
perfusion and oxygenation are supply parameters (preload, afterload and heart rate are determinants of myocardial demand)
165. signs and symptoms of diabetes insipidus include all of the following except:
b. increased urine osmolarity
d. serum hyperosmolarity
-b. increased urine osmolarity
the vast amounts of urine produced by patients with diabetes insipidus have relatively no solute and thus very minimal osmolarity
166. The preservative in halothant that provides stability is:
a. absolute alcohol
b. methylene blue
Thymol o.01% is added to halothane liquid as a stabilizer to prevent breakdown during storage
167. All of the following are contraindications to using nitrous oxide except:
a. bowel obstruction
b. hiatal hernia
c. air embolism
-b. hiatal hernia
hiatal hernia does not involve a closed gas space in the body; therefore, it would not be expanded by the administration of nitrous oxide.
168. Inhalation anesthetic agents are metobilized by the:
a. monoamine oxidase system
c. microsomal enzymes
-c. microsomal enzymes
some volatile anesthetics are metabolized by the liver by drug metabolizing enzymes known as microsomal enzymes
169. Where is nitrous oxide metabolized?
trace amounts of nitrous oxide are metabolized in the intestines by intestinal bacteria
170. what percentage of isoflurane is metabolized?
isoflurane is resistant to metabolizm and thus is converted in less than 1% of the administration dose to nontoxic byproducts.
171. Hepatic dysfunction occurs most often after repeated administration of halothane to what group of patients?
a. young adults
b. pediatric patients
c. obese middle aged females
d. middle aged males
-c. middle aged females
the national halothane study indicated that obese middle aged women are the most susceptible to halothane toxicity.
172. What is the diagnostic test for malignant hyperthermia?
a. elevated lactate dehydrogenase
b. elevated creatnine phsophokinase
c. halothane-caffiene contracture test
d. genetic test of the ryanodine receptor
-c. halothane-caffiene contracture test
173. Your patient is in the sitting position. Where should you place the transducer to measure mean arterial blood pressure to monitor perfusion pressure at the brain?
a. it doesnt matter where the transducer is placed
b. place the transducer at the right sternal border between the 3rd and 6th intercostal space
c. place the transducer at the level of arterial catheter insertion site
d. place the transducer at the level of the external ear canal, which is at the level of the circle of willis.
-d. place the transducer at the level of the external ear canal, which is at the level of the Circle of Willis
174. Which five nreves may be injured in lithotomy position?
a. common peroneal, sciatic, femoral, saphenous and obturator nerves
b. deep peroneal, sural, posterior tibial, saphenous and femoral nerves
c. common peroneal, superficial peroneal, posterior tibial, sciatic and obturator nerves
d. sciatic, femoral, pudendal, posterior tibial, and common peroneal nerves
-a. common peroneal, sciatic, femoral, saphenous and obturator nerves
Nerves that supply the lower extremities are often damaged because of compression or stretching with improper positioning or padding
175. Why is the axillary roll placed undeer the patient in the lateral decubitus position?
a. to prevent compression of the brachial plexus and subclavian vessels near the first rib and thus prevent thoracic outlet syndrome
b. to allow the thorax to hang free, thus minimizing loss of functional residual capacity and obstruction to venous return
c. to lift the thorax and relieve pressure on the axillary neurovascular bundle and to prevent reduced blood flow to the hand
d. to prevent the patient from sliding more laterally, causing ventral circumduction of the dependent shoulder and the potential for suprascapular nerve injury.
-c. to lift the thorax and relieve pressure on the axillary neurovascular bundle and to prevent reduced blood flow to the hand
A small support shold be placed just caudal to the downside axilla to prevent decreased blood flow to the hand
176. What is the most frequently damaged nerve in the lower extremity?
a. sciatic nerve
b. common peroneal nerve
c. femoral nerve
d. anterior tibial nerve
-b. common peroneal nerve
The common peroneal nerve may be injured when the head of the fibula (lateral aspect of the knee) is compressed against the leg support or insufficiently padded
177. What nerve is damaged if the inside of the knee is compressed?
a. saphenous nerve
b. obturator nerve
c. anterior tibial nerve
d. common peroneal nerve
-a. saphenous nerve
The saphenous nerve may be injured when the medial tibial condyle is compressed by the leg supports.
178. The rate of induction with an inhalation anesthetic varies inversely with which property of the agent?
a. oil/gas solubility
b. blood/gas solubility
c. vapor pressure of the agent
d. none of the above
-b. blood/gas solubility
The speed of induction and emergence of an anesthetic gas is determined by its blood/gas solubility. The lower number, the faster the anesthetic.
179. all of the following are ultra short acting barbiturates except:
-d. pentobarbital (nembutal) is a short acting drug whose duration is in the range of 4 to 8 hours.
180. The termination of action of thiopental is via:
a. distribution to the skeletal muscles
d. reductive enzymes
Patients emerge from thiopental effects due to redistribution from the brain to non-neural sites. This is true of all induction drugs.
181. What drug should not be administered with a monoamine oxidase inhibitor?
meperidine metabolism is affected by MAO inhibitors, possibly resulting in seizures and death
182. Use of barbiturates is contraindicated in what disease?
a. muscular dystrophy
b. graves disease
barbiturates may induce the enzyme aminolevulinic acid synthetase resulting in a precipitation of an attack in genetically susceptible patients with prophyria
183. Use of droperidol is contraindicated in what disease?
a. diabetes mellitus
d. muscular dystrophy
-b. parkinson's disease
droperidol blocks dopamine in the brain; therefore it is contraindicated in patients with Parkinson's disease because of it's extrapyramidal side effects.
184. Which antimuscarenic exhibits the least central nervous system toxicity?
Glycopyrollate is a quartenary ammonia compound and does not pass the blood brain barrier
185. Central nervous system toxicity due to anticholinergic drugs can be treated with:
physostigmine unlike other anticholinesterases, passes the blood brain barrier and will relieve central nervous system symptoms.
186. What percent of neuromuscular blockade is achieved if 2 of 4 twitches from train of four stimulation of the ulnar nerve can be elicited?
a. 50 %
b. 75 %
c. 80 %
d. 90 %
-c. 80 %
Two responses out of four indicates a degree of paralysis of approximately 80%.
1 of 4=90%;
2 of 4=80%
3 of 4=70%;
4 of 4= less than 70%
187. The final metabolic product of nitroprusside is:
nitroprusside is made of 5 cyanide molecules per molecule of the drug. They are released during metabolism of this agent.
188. A drug that follows first order kinetics will be eliminated from the body at:
a. a constant amount per time
b. a half life at a time, & depends on the amount of the drug
c. the same number of milligrams per hour
d. the elimination time varies
188b. What is zero order kinetics?
-b. A half life at a time & depends on the amount of drug
In first order kinetics it follows that a drug will be eliminated in a constant % per half life, for example, 10% per hour or 50% of the drug every 3 hours (it is based on the amount of the drug present)
184b. ETOH follows zero order and is eliminated at a constant rate per hour no matter how much is present. Etoh drops 0.1 percent every 5 hours. So it will take a 0.4 blood alcohol will take 20 hours.
189. what is the classification of a 140 kg patient who must undergo emergency surgery for a bowel obstruction?
a. ASA 1E
b. ASA 3E
c. ASA 4E
d. ASA 2E
-d. asa 2E
A patient this large and thus ASA 2. A bowel obstruction is an emergency, thus the E designation.
190. List three diseases an ASA3 patient may have:
a. angina pectoris, chronic obstructive pulmonary disease and prior myocardial infarct
b. essential HTN, diabetes mellitus and morbid obesity
c. anemia, chf and persistent angina pectoris
d. extremes of age, chronic bronchitis and hepatic dysfunction
a. angina, copd, prior MI
ASA 3 signifies having chronic and serious disorders present. The first 3 are the most significant of all the listed disorders
191. Allof the following are the pharmacologic effects of dropiridol except:
b. extrapyramidal signs
c. antiemetic properties
dropiridol blocks alpha receptors, resulting in vasodilation in the periphery
192. What nerve is injured if the arm is malpositioned with the elbow at the side of the table?
a. sciatic nerve
b. median nerve
c. radial nerve
d. ulnar nerve
-d. ulnar nerve
the ulnar nerve is the most frequently injured nerve under anesthesia. This results from improper positioning and panic when adjusting the arms.
193. Elevation of the kidney rest compresses which structure and leads to what response?
a. The aorta is compressed, which causes lower extreminty ischemia and hypertension
b. the inferior vena cava is compressed, which causes a marked reduction in venous return and hypotension
c. the abdominal viscera are compressed which causes ventilation/perfusion mismatch
d. the common peroneal nerve is compressed, which results in loss of sensation over the dorsum of the foot
-b. the inferior vena cava is comrpessed, which causes marked reduction in venous return and hypotension
A kidney rest compresses the flank area, resulting in pressure on the vena cava and hypotension
194. Anticholinergic blocks which muscarenic receptor subtype?
4. M-1, M-2, M-3
-d. M-1, M-2, M-3
M-1 receptors are neuronal, M-2 are in the heart and M-3 are in smooth muscle and glands. All three types are blocked by the common antimuscarenic medications.
195. Pseudocholinesterase metabolizes:
Ester-type local anesthetics are metabolized by hydrolysis with the enzyme cholinesterase
196. During the onset of neuromuscular blockade, in the fourth twitch is eliminated in the train of four, the percent of blockade is:
Loss of one twitch in the train of four indicates a percentage of blockade in the high 70s
197. The maximum amount of air that can be inhaled from the resting end expiratory level is:
a. tidal volume
b. vital capacity
c. inspiratory capacity
d. inspiratory reserve volume
-C. inspiratory capacity
The inspiratory capacity is made up of the inspiratory reserve volume plus the tidal volume
198. muscle relaxants distribute to what body compartment?
a. skeletal muscle
b. intracellular fluid
c. extracellular fluid
d. vessel poor organs
-c. extracellular fluid
muscle relaxants are 100% water soluble in the body at all times and thus distribute to the body's extracellular water only
199. the onset of action of what antimuscarenic parallels the onset of edrophonium?
d. all of the antimuscarenics parallel the rapid onset of edrophonium
Atropine has the fastest onset among the listed drugs, which correlates with the fast onset of edrophonium
200. Administration of an anticholinergic drug before the anticoholinesterases will minimize which effect?
a. nicotinic receptor antagonism
b. muscarenic receptor antagonism
c. nicotinic receptor stimulation
d. muscarenic receptor stimulation
-d. muscarenic receptor stimulation
Excess acetylcholinergic generated by the anticholinesterase drug will stimulate muscarenic receptors unless they are blocked within the anticholinergic drug.
201. The "concentration effect" or "overpressure" during induction of anesthesia refers to:
a. the blood gas coeffecient of an anesthetic varies with concentration
b. the higher the concentration administed, the faster the increase in alveolar concentration
c. the second gas effect
d. anesthetic overdose
-b. the higher the concentration administered, the faster the increase in alveolar concentration
giving higher than necessary concentrations during initial administration of an anesthetic to speed onset is referred to as the concentration effect
202. Naltrexalone (Re Via), Naloxone (narcan) and nalmefene (revex) are:
a. pure agonist
b. partial agonists
c. partian agonist/antagonists
d. pure antagonists
-d. pure antagonists
These three drugs are pure opiate receptor agonists that work on all receptor subtypes
203. The "truncal rigidity" that may occur with fentanyl can be relieved by:
a muscle relaxant will relieve the tight chest produced by rapid administration of high potency opiates
204. Which fibers are not cholinergic?
a. preganglionic sympathetic
b. postganglionic parasympathetic
c. postganglionic sympathetic
d. preganglionic parasympathetic
-c. postganglionic sympathetic
Postganglionic sympathetic fibers are adrenergic as they release norepinephrine
205. Which of the following would be expected to produce the most reliable anesthesia/amnesia?
although all of the listed agents may produce some amnesia, the benzodiazepines are the most reliable and predictable amnestic drugs.
206. Nystagmus is a characteristic of which "stage" of anesthesia?
a. stage 1
b. stage 2
c. stage 3
d. stage 4
-b. stage 2
Nystagmus is characteristic of the excitement stage during anesthetic administration which is noted as stage 2
207. The enzyme primarily involved in the biotransformation of exogenous catecholamines is:
a. monoamine oxidase
b. cytochrome p450
c. catechol-o-methyl transferase
-a. monoamine oxidase (MAO)
biogenic amines are metabolized in the body primarily by the mitochondrial enzyme monoamine oxidase
208. The theraputic index by definition is:
a. 25% lethal dose/ 25% effective dose
b. 50% lethal dose/ 50% effective dose
c. 75% lethal dose/ 75% effective dose
d. 90% lethal dose/ 90% effective dose
-b. 50% lethal dose/ 50% effective dose
Theraputic index, a measure of drug safety, is defined as LD50/ED50
209. Anesthetic partial pressure in the brain depends on:
a. solubility of the agent
b. anesthetic partial pressure in the alveoli
c. minimal alveolar concentration of the agent
d. second gas effect
-b. anesthetic partial pressure in the alveoli
There is always a direct correlation between the brain and lung concentrations because anesthetics are freely diffusible through biologic membranes.
210. Dissociative anesthesia is a term applied to anesthesia produced by the administration of:
Ketamine blocks association pathways in the brain and thus is referred to as producing dissociative anesthesia
211. Dual block can be caused by:
a. a nondepolarizing relaxant
b. small amounts of depolarizing relaxants
c. very large doses of depolarizing relaxants
d. administration of both nondepolarizing and depolarizing
-c. very large doses of depolarizing relaxants
Administration of large amounts (usually greater than 500 mg) of sux may produce a desensitization block sometimes refrerred to as a dual block
212. The most sensitive muscles to the paralyzing effects of neuromuscular blocking drugs are:
a. abdominal muscles
b. limb muscles
c. jaw muscles
d. eye muscles
-d. eye muscles
even the small doses of muscle relaxants may produce eyelid muscle paralysis and weakness resulting in blurred vision
213. The most serious systemic toxicity with local anesthetics is:
a. cardiac arrhythmias
b. liver damage
c. respiratory depression
The most serious toxicity resulting from an overdose of local anesthetic is central nervous system stimulation, resulting in convulsions
214. A drug's plasma half life is:
a. Its 50% maximal response
b. the time required for plasma drug concentration to be decreased by 50%
c. its duration of action
d. its onset of action
-b. the time required for plasma drug concentration to be decreased by 50%
The beta half-life of a drug indicates elimination. It usually takes four to five half lives to eliminate a drug
215. The minimal alveolar concentration value of an agent is defined as:
a. potency of an agent
b. speed of induction and emergence
c. alveolar concentration where 50% of patients DO NOT RESPOND to surgical stimuli
d. directly proportional to the blood/gas solubility coefficient
-c. alveolar concentration where 50% of patients do not respond to surgical stimuli
The minimal alveolar concentration (MAC) is an indication of anesthesia depth and is designated as the 50% point.
216. The activity of acetylcholine released from cholinergic nreve endings is terminated by:
a. hydrolysis catalyzed by acetylcholinesterase
b. presynaptic neuronal uptake through an active pump
c. presynaptic neuronal uptake by endocytosis
d. monamine oxidase
-a. hydrolisis catalyzed by acetylcholinesterase
acetylcholinesterase is the isoenzyme present in the neuromuscular junction that metabolizes acetylcholine
217. Drugs crossing biomembranes generally do so by which of the following processes?
a. diffusion through aqueous ion channels
b. diffusion through membrane lipid
c. permeation by active pump mechanisms
-b. diffusion through lipid membrane
Drugs have molecules too large to move through channels; therefore, they must have lipid solubility or be actively transported to move through biologic membranes.
218. The ED50 of a drug is defined as:
a. the response elicited when one half of the theraputic dose is administered
b. the dose that elicits a theraputic response in 50% of patients
c. one-half of the ED100
d. the threshold dose
-b. the dose that elicits a theraputic response in 50% of patients
ED50 represents the effective dose to reach half -efficacy on a dose response scals
219. A drug having a high LD50 and a low ED50:
a. is unsafe for human use
b. has a high theraputic index and is therefore very dangerous
c. has a high theraputic index and is therefore very safe
d. has a low theraputic index and should therefore be used with care
-c. has a high theraputic index and is therefore very safe
A high theraputic index indicates a very safe drug because the lethal dose is much higher than the effective dose.
220. What do the letters I.T. or Z79 indicate on an endotracheal tube?
a. the endotracheal tube has passed inspection
b. endotracheal tube material free of toxic properties
c. indicates internal diameter of the tube
d. indicates length of the tube
-b. endotracheal tube material free of toxic properties
I.T. on an endotracheal tube means "Implant Tested" to ensure non-toxicity, and Z79 stands for the Z79 committee on anesthesia equipment of the American National Standards Institute and signifies that the material is nontoxic to tissues as well.
221. Pulse oximetry functioning is an example of:
a. Beer's law
b. Dalton's law
c. Charle's law
d. Reynold's law
Beer's law states that at a constant light intensity and hemoglobin concentration, the intensity of light transmitted through the sample is a log function of the oxygen saturation of hemoglobin
222. Of the following, which interferes with pulse oximetry?
b. hemoglobin F
Methemoglobin absorbs both red and infrared light. At a high methemoglobin level, the saturation will be 85% regardless of the actual PO2.
223. Clinical accuracy of pulse oximetry is within:
Clinical accuracy is typically reported to be +/- 2% to 3% for a range of saturation between 70-100%.