c3. BASIC PRInciples A (1-75) Flashcards
- If a patient is on MAO therapy, which is the vasopressor of choice>
a. mephentermine
b. phenylephrine
c. ephedrine
d. metaraminol
-b. direct acting vasopressors should be used in MAO therapy. Phenylephrine is the only direct-acting drug of the listed choices.
- A solution containing a 1:200,000 concentration equals:
a. 0.5 mcg/mL
b. 1 mcg/mL
c. 5 mcg/mL
d. 50 mcg/mL
c. 5 mcg/mL
Based on a system of grams per liter, a 1: 200,000 concentration is equal to 5 mcg/mL
- What premedication might be important in the diabetic patient which peripheral neuropathy.
a. sodium citrate to increase gastric pH
b. metoclopramide to increase gastric emptying
c. glycopyrrolate to decrease oral secretions
d. cimetidine for H2 receptor antagonism
-b. metoclopramide (reglan) to increase gastric emptying
Diabetic patients often have gastric atony; thus, a gastrokinetic agent such as reglan may be useful to ensure an empty stomach
- Which of the following would be a possible indication of a venous air embolism?
a. increased ETco2
b. decrease ETco2
c. increased arterial blood pressure
d. decreased pulmonary artery pressure
-b. decreased ETco2
Venous air embolism, such as seen in sitting procedures, may be detected by a reduced end expired CO2, resulting from the ventilation/perfusion mismatch.
- Which of the following IV solutions is best avoided in the neurosurgical patient?
a. balanced salt solution
b. dextrose and water
c. normal saline
d. lactated ringer’s solution
-b. dextrose and water
Glucose containing solutions are avoided in all neurosurgical patients because they can exacerbate ischemic damage and cerebral edema (glucose is hypertonic and will draw water to the site)
- One of the quickest ways to decrease intracranial pressure in the acute situation is:
a. cerebrospinal fluid drainage
b. corticosteroid administration
c. hyperventilation
d. loop diuretics
-c. hyperventilation reduces brain volume by decreasing cerebral blood flow through cerebral vasoconstriction. For every millimeter of mercury change, cerebral blood flow decreases by approximately 4%.
- In the patient with increased intracranial pressure, what should the ideal PaCO2 level be?
a. 30-35 mmHg
b. 22-29 mmHg
c. 25-30 mmHg
d. 35-40 mmHg
-c. Hyperventilation to tge PaCO2 of 25 to 30 mmHg is the mainstay of acute and subacute treatment for intracranial hypertension.
- Which inhalation agent increases pulmonary vascular resistance?
a. halothane
b. enflurane
c. nitrous oxide
d. isoflurane
-c. nitrous oxide
Most inhalation anesthetics in the absence of a pathologic process have little effect on or decrease pulmonary vascular resistance. Nitrous oxide may increase resistance, especially in patients with pulmonary hypertension.
- The operation of what monitoring device uses Lambert-Beer law?
a. pulse oximetry
b. ETCO2 monitoring
c. pneumatic blood pressure cuff
d. mass spectrometry
-a. pulse oximetry
The lambert beer law relates to the observation that oxygenated and reduced hemoglobin differ in their absorption of red and infrared light. Pulse oximetry monitoring is based on this principle.
- How do you calculate cardiac output?
a. CO = SVR x PVR
b. CO = SV x HR
c. CO = HR x SVR/2
d. CO = SV x PVR
-b. SV x HR
Cardiac output is equal to stroke volume times heart rate and is expressed in “liters/minute”. The normal range is 4 to 8
- How do you calculate cardiac index?
a. CI = SV x PVR
b. CI =CO x BSA
c. CI =CO/BSA
d. CI =NAP - CVP X BSA
-c. CI = CO/BSA
Cardiac Index is derived from the cardiac output divided by the body surface area and is expressed as “liters/minute/meters squared”. normal range is 2.5 to 4
- What is the normal value of a cardiac index?
a. 2.4-4.2 L/min
b. 5-6 L/min
c. 2-3 L/min
d. 5-6 L/min
-a. 2.5-4.2 L/min
cardiac output is derived from the cardiac output divided by body surface area and is expressed as liters per minute per meter squared
- How do you calculate systemic vascular resistance?
a. SVR = PVR X SV
b. SVR = (MAP-CVP) X 80/CO
c. SVR = MAP-CO/80
d. cannot determine
-b SVR = (MAP-CVP) X 80/CO or (MAP-CVP /CO X 80
Systemic vascular resistance is calculated from this formula
- What is the normal value for SVR?
a. 100-200 L/min
b. 900-1000 L/min/m2
c. 5-6 dynes/sec/cm-5
d. 1200-1500 dynes/sec/cm-5
-d. 1200-1500 dynes/sec/cm-5
that is the normal SVR
- All of the following are complications of central venous catheters except:
a. erratic and inacurate readings
b. infection
c. venous air embolism
d. catheter shearing
-a. erratic and inacurate readings
When proprely functioning venous catheters rarely give erratic and inacurate readings; however, the other complications are always possible
- Which vessel is at greatest risk of accidental puncture if a left internal jugular approach is used to place a central venous line?
a. subclavian vein
b. external jugular vein
c. carotid artery
d. subclavian artery
-c. carotid artery
Puncture of the carotid artery is especially prominent in left internal jugular cannulation. Using the right internal jugular is safer, with less likelihood of arterial puncture.
- One way to decrease the risk of venous air embolism during central line placement might include:
a. have the patient hold his or her breath during the procedure
b. administer vasopressors to increase blood pressure
c. place the patient in trendelenberg position
d. there is no way to prevent it
-c. place the patient in trendelenberg position
Air embolism can be avoidied by using the trendelenberg positon to increase venous pressure, which limits the possiblity of the entrance of air through the catheter.
- A patient with myasthenia gravis is at major surgical risk for:
a. aspiration pneumonitis
b. hypothermia
c. postoperative ventilatory failure
d. prolonged muscle paralysis after succinylcholine administration
-c. postoperative ventilatory failure
Although muscle strength frequently seems adequate early after anesthesia and surgery, many patients with myasthenia gravis experience deterioration and require ventilatory support after surgery.
- The patient complains of an intense, searing pain upon regional anesthetic injection; what most likely occured?
a. patient really just felt paresthesia
d. the needle hit the bone
c. intraneuronal injection
d. intra-arterial injection
-c. intraneuronal injection
Accidentally pinning a nerve against an ajacent structure increases the likelihood of intraneuronal injection. When this occurs, the injection should be stopped and the needle re-placed
- Name the induction agent of choice for a patient with cardiac tamponade?
a. thiopental sodium
b. propofol
c. etomidate
d. ketamine
-d. ketamine
Ketamine, by releasing catecholamines supports blood pressure. Patients with cardiac tamponade are decompensated and any cardiac depressant drug may cause precipitous hypotension.
- Which lung volume is reduced under anesthesia?
a. total lung capacity
b. residual volume
c. functional residual capacity
d. vital capacity
-c. FRC (functional residual capacity)
Induction of anesthesia consistantly produces a 15-20% reduction in functional residual capacity beyond which occurs in supine position.
- Why does functional residual capacity decreases in the supine or prone position?
a. compliance is reduced as abdominal contents push up against the diaphragm
b. intrathoracic blood volume decreases
c. pulmonary lung resistance increases as a patient’s position changes
d. there is no change in functional residual capacity
-a. compliance is reduced as abdominal contents push up against the diaphragm
Loss of diaphragmatic tone allows abdominal contents to rise up against the diaphragm. The higher position of the diaphragm decreases lung volumes.
- Which intravenous anesthetic directly appresses the adrenal cortex?
a. thiopental sodium
b. propofol
c. etomidate
d. ketamine
-c. etomidate
etomidate inhibits the conversion of cholesterol to cortisone by inhibiting conversion enzymes. This results in adrenal suppression.
- Numbness over the lateral aspect of the thigh may be caused by damage to what nerve?
a. lateral femoral cutaneous
b. common peroneal nerve
c. sciatic nerve
d. ulnar nerve
-a. lateral femoral cutaneous
The lateral femoral cutaneous nerve may be entrapped in the anetrior iliac spine under the inguinal ligament resulting in numbness in the thigh.
- Complications unique to nasotracheal intubation include all of the following except:
a. epistaxis
b. dislogdement of pharyngeal tonsils (adenoids)
c. tracheo-esophageal fistula
d. maxillary sinusitis
-c. tracheo-esophageal fistula
Complications of nasotracheal intubation may include epistaxis, dislodgement of pharyngeal tonsils, eustachian tube obstruction, maxillary sinusitis, bacteremia and gastric distention.
- Dextrose containing solutions are avoided in neurosurgery because they:
a. decrease urinary output
b. provide inadequate intravascular volume
c. promote cerebral edema
d. increase cellular metabolism
-c. promote cerebral edema
Dextrose in water (although isotonic) ACTS as a hypotonic solution, thus increasing brain water which may lead to cerebral edema.
- How much CO2 is dissolved in arterial blood?
a. 10 ml CO2/dL of blood
b. 5 ml CO2/dL of blood
c. 1.5 ml CO2/dL of blood
d. 2.5 ml CO2/dL of blood
-d. 2.5 mL CO2/dL of blood
Carbon dioxide is more soluble in blood than oxygen. It dissolves in plaasma as well as erythrocytes and represents approx 2.5 ml/dl of blood
- At what postconceptual age should a premature infant be scheduled for elective or outpatient surgery?
a. 30 weeks
b. 60 weeks
c. 120 weeks
d. 60 days
-b. 60 weeks
Premature infants younger than 60 weeks postconception are prone to postoperative episodes of obstructive and central apnea for up to 24 hours after surgery.
- Prematurity is deined as birth before ____ weeks gestation?
a. 20
b. 37
c. 45
d. 47
-b. 37
Prematurity is birth before 37 weeks gestation. This is in contrast to “small gestational age” which may describe a full term infant.
- What is the maintenance fluid requirement for a 5 kg patient?
a. 20 ml/hr
b. 22 ml/hr
c. 10 ml/hr
d. 14 ml/hr
-a. 20 ml/hr
The fluid requirements can be determined by the formula of: 4 ml/hr for the first 10 kg; 2 ml/kg for the nest 10 kg; and 1 ml/kg for the remaining kilograms.
- What is the maintenance fluid requirement for a 25 kg patient?
a. 25 ml/hr
b. 54 ml/hr
c. 65 ml/hr
d. 75 ml/hr
-c. 65 ml/hr The formula is 25 kg= 10 kg + 10 kg + 5 kg; using the 4-2-1 formula. 10 x 4=40 10 x 2=20 5 x 1=5
- What is the mainstay therapy for acute/subacute management of intracranial pressure?
a. diuretics
b. normovolemia
c. hyperventilation
d. antihypertensives
-c. hyperventilation
Hyperventilation is a rapid and effective method for acute management of increased ICP. Co2 should be kept in the 25-30 mmHg range.
- By what mechanism does citrate produce its anticoigulant effects?
a. increases prothrombin time
b. binds to calcium
c. binds to sodium
d. decreases factor VIII
-b. binds to calcium
Citrate binds calcium and may result in both anticoagulation and cardiac depression with rapid transfusion. Cardiac depression results from hypocalcemia.
- What preservative/ anticoagulant substance found in packed red blood cells can cause toxicity.
a. calcium
b. citrate
c. phosphate
d. bicarbonate
-b. citrate
citrate may produce toxicity resulting in anticoagulation and cardiac depression with massive blood transfusions
- Packed red blood cells should not be recostituted in lacteted ringers solution because:
a. the calcium in LR may cause clotting if mixed with RBCs
b. the hypertonic solution may cause hemolysis
c. a metabolic acidsis resluts when they are administered together
d. a metabolic alkalosis results when they are administered together
-a. the calcium in LR may cause clotting if mixed with RBCs
calcium may clot when mixed with RBCs, therefore only hang RBCs with normal saline
- What type of blood should be given to a patient who’s blood type is unknown?
a. O positive
b. AB positive
c. O negative
d. none
-c. O negative
O Rh negative blood is known as the universal donor because it is the least likely to initiate a transfusion reaction
- Which muscles abduct the vocal cords?
a. posterior cricoarytenoids
b. vagus nerve
c. lateral cricoarytenoid
d. strap muscles
-a. posterior cricoarytenoids
The posterior cricoarytenoids abduct (open) the vocal cords where as the lateral cricoarytenoids are the primary adductors (closers).
- The larynx is composed of nine cartilages; which of the following is not a paired cartilage?
a. arytenoid
b. corniculate
c. thyroid
d. cuneiform
-c. thyroid
The three UNPAIRED cartilages are the thyroid, cricoid and epiglottis. The three PAIRED cartilages are the arytenoid, corniculate and cuneiform
- Which nerve supplies sensory innervation below the vocal cords?
a. branch of the trigeminal
b. superior laryngeal
c. phrenic nerve
d. recurrent laryngeal
-d. recurrent laryngeal
The recurrent laryngeal nerve provides sensory innervation below the cords and motor innervation for ABDUCTION of the cords.
- Which of the following is not an unpaired cartilage of the larynx?
a. epiglottis
b. cricoid
c. arytenoid
d. thyroid
-c. arytenoid
The three unpaired cartilages are the thyroid, cricoid and epiglottis. The three paired are the arytenoid, corniculate and cuneiform
- Which laryngeal muscle has motor innervation by the external branch of the superior laryngeal nerve?
a. posterior cricoarytenoid
b. cricothyroid
c. lateral cricoarytenoid
d. thyroid cartilage
-b. cricothytoid
The external branch of the superior laryngeal nerve provides motor innervation to the cricothyroid muscle, which tenses the vocal cords.
- Unilateral paralysis of the recurrent laryngeal nerve results in:
a. complete airway obstruction
b. stridor and respiratory distress
c. ipsilateral cord paralysis, hoarse voice
d. no changes
-c ipsilateral cord paralysis, hoarse voice
Unilateral damage to this nerve results in hoarseness. Bilateral damage to this nerve results in stridor, respiratory distress and aphonia.
- What is the maximum PaO2 that can be achieved on room air?
- 90 mmhg
- 96 mmhg
c. 21 mmhg
d. 104 mmhg
-d. 104 mmHg
Under normal conditions there is 21% oxygen in the atmosphere; and , considering deadspace, the tension that can be achieved in the blood is 102 to 104 mmHg.
- What is the purpose of incentive spirometry?
a. increase residual volume
b. decrease deadspace
c. prevent atelectasis
d. increase cardiac output
-c. prevent atelectasis
Incentive spirometry is a form of voluntary deep breathing in which patients are given an inhaled volume as a goal to achieve. The preoperative inspiratory capacity should be the post operative goal.
- Which of the following is not an adverse effect of sucinylcholine?
a. increased intraocular pressure
b. rapid muscle relaxation
c. hyperkalemia
d. myalgia
-b. rapid muscle relaxation
One of the most desirable properties of succinylcholine is its rapid onset of action. It has the most rapid onset among relaxants.
- The reaction between CO2 and soda lime is classified as:
a. neutralization
b. reduction
c. combustion
d. vaporization
-a. neutralization
Neutralization of carbon dioxied results in thed production of calcium carbonate, water and heat.
- Which nerve is most commonly injured during anesthesia?
a. sciatic nerve
b. anterior tibial nerve
c. femoral nerve
d. ulnar nerve
-d. ulnar nerve
Injury to the ulnar nerve is the most common postoperative neuropathy. The nerve is frequently injured when stretched or compressed against the posterior aspect of the medial epicondyle of the humerus.
- Which class of antibiotics is known to potentiate nondepolarizing muscle relaxants?
a. penicillins
b. cephalosporins
c. aminoglycosides
d. sulfonamides
-c. aminoglycosides; by chelating calcium, may prolong the action of muscle relaxants. This is a rare, but potentially serious drug reaction.
- Which of the following does not contribute to perioperative hypothermia?
a. surgical exposure
b. operating room environment
c. inhibition of thermoregulation
d. increased metabolic rate
-d. increased metabolic rate
Increases in metabolic rate tend to produce heat, resulting in fever. Anesthetics by nature decrease metabolic rate.
- Intraoperative hyperthermia would NOT be caused by which of the following?
a. malignant hyperthermia
b. surgical exposure
c. increased metabolic rate
d. excessive environmental warming
-b. surgical exposure
surgical exposure of the patient (especially of large body cavities) tends to produce hypothermia during anesthesia.
- Warfarin-like drugs act as anticoagulants by:
a. inhibiting vitamin k dependent factors
b. inhibiting the intrinsic clotting cascade
c. inhibiting the extrinsic clotting cascade
d. inhibiting platelets
-a. inhibiting vitamin k dependent factors
Warafin like drugs inhibit vitamin K dependent factors II,VII, IX and X
- The effects of warafin can be reversed in an emergency by:
a. giving fresh frozen plasma or whole blood
b. giving vitamin k (phenytonadione)
c. administering protamine sulfate
d. platelet administration
-a. give fresh frozen plasma or whole blood
Vitamin K reverses warfarin because it (warfarin) acts by inhibiting vitamin k dependent factors. However, reversal with vitamin K is slow and can take from 8 hours to 1 week. Administration of FFP provides the clotting factors necessary in an emergency.
- All of the following are possible causes of thrombocytopenia except:
a. liver disease
b. massive blood transfusion
c. renal disease
d. DIC
-c. renal disease
although renal disease may result in anemia, it does not produce decreased platelet counts.
- The first sign of hemolytic transfusion reaction in the anesthetized patient may be:
a. chills
b. temperature increase
c. hypertension
d. hematuria
-d. hematuria
The onset of red urine due to free plasma hemoglobin may be the first sign of a blood reaction
- All of the following are treatments for acute hemolytic transfusion reactions except:
a. alkalinize the urine with bicarbonate
b. administration of 2 units of PRBCs
c. support blood pressure to maintain renal flow
d. administration of iv fluid at 150 ml/hr
-b. administration of 2 units PRBCs
Administering blood would be unnecessary to treat a transfusion reaction. The other choices are common and necessary to maintain urine output and renal blood flow.
- The approximate blood volume of an adult is:
a. 5000 ml
b. 10,000 ml
c. 3000 ml - 3500 ml
-a. 5,000 ml
The blood volume of an average (70 kg) patient is 70 ml/kg or 5000 ml
- The hematocrit of packed red blood cells is approximately:
a. 50%
b. 90%
c. 60%
d. 70%
-d. 70%
Whole blood has a hematocrit of ~ 40% whereas packed red blood cells have a hct of ~ 70%. Because plasma has been removed, cell count increases.
- common signs of citrate intoxication from banked blood include all of the following except:
a. narrow pulse pressure
b. oozing at the surgical site
c. hypercalcemia
d. hypotension
-c. hypercalcemia
Citrate intoxication resluts from the ability of citrate to bind to calcium, causing hypocalcemia, which results in anticoagulation and cardiovascular depression.
- The citrate in banked blood causes;
a. hypokalemia
b. hypercalcemia
c. hypocalcemia
d. hyperkalemia
-c. hypocalcemia
citrate binds calcium causing systemic hypocalcemia
- During general anesthesia, the 3 common signs of a hemolytic infusion reaction include all of the following except:
a. fever
b. hematuria
c. excess bleeding and oozing at surgical site
d. hypertension
-d. hypertension
common signs of hemolytic infusion reaction are fever, chills, chest pains, bleeding, hypotension, hematuria, flushing and nausea
- After 24 hours of storage, what percent of platelets are viable?
a. 20%
b. 10%
c. 5%
d. 25%
-b. 10%
Storage of platelets at 4 degrees celcius for 24 hours causes a loss of 90% of viable transfusate. They should be used within 6 hours of preparation.
- Common acid-base and electrolyte disturbances of massive transfusion of banked blood include all of the following except:
a. hypernatremia
b. hypocalcemia
c. hyperkalemia
d. metabolic acidosis
-d. metabolic acidosis
Banked blood contains increased amounts of hydrogen and thus would tend toward acidosis. This however is not common and administration of bicarb is rarely necessary (in other words; there is acidosis but not significant).
- In patient’s with severe hyponatremia, it is safe to increase serum sodium by:
a. 1-2 meq/hr
b. 5 meq/hr
c. 10 meq/hr
d. 20 meq/hr
-a. 1-2 meq/hr
Too rapid correction of hyponatremia may result in cerebral edema and CHF; therefore, correction should proceed cautiously and slowly. Symptoms will improve within 24 hours.
- the following are all manifestations of hypokalemia seen on an ECG except:
a. tall peaked T weaves
b. widened QRS
c. T wave depression
d. prominent U waves
-a. tall peaked T waves
ECG changes with hypokalemia include widened QRS complex, ST depression, T wave depression, U wave prominence and first degree atrio-ventricular block
- A clinical mainfestation of hypokalemia is:
a. ST segment elevation
b. hypopolarization of the cardiac cell
c. shortened PR interval
d. hyperpolarization of the cardiac cell
-d. hyperpolarization of the cardiac cell
Acute hypokalemia causes hyperpolarization of the cardiac cell, leading to arrhythmic activity
- All of the following are changes that may be noted on an ECG in a patient with hyperkalemia except:
a. PR prolongation
b. flattened T waves
c. widened QRS
d. asystole
-b. flattened T waves
Hyperkalemia results in tall peaked T waves, prolonged PR interval, widened QRS, a decrease in the amplitude of P waves and ultimately cardiac arrest.
- How many half lives does it take to eliminate 75% of the dose of a drug?
a. 1
b. 2
c. 3
d. 4
-c. 2 Half life is the time it takes for a drug level to fall by one half. After: -One half life, 50% is eliminated. -Two half lives=75% is eliminated; -Three half lives=87.5% is eliminated; -Four half lives=95% is eliminated.
- pulmonary edema may be treated with all of the following except:
a. calcium channel blockers
b. morphine
c. diuretics
d. sodium nitroprusside
-b. calcium channel blockers
calcium channel blockers would cause cardiac depression and possibly contirbute to pulmonary stasis by decreasing cardiac function
- All of the following are indications for placement of a permanent pacemaker except:
a. first-degree heart block
b. sick sinus syndrome
c. sinus bradycardia
d. third-degree heart block
-a. first degree heart block
First degree heart block is relatively asymptomatic and ususally does not require therapy. More severe heart block may be treated with a pacemaker.
- all of the following decrease serum K+ except:
a. glucagon
b. calcium chloride
c. kalexalate (sodium polystyrene sulfonate)
d. hemodialysis
-a. glucagon
Glucagon would be contraindicated because it would lower insulin levels. Insulin increases cellular uptake of potassium and is commonly given along with the other drugs listed to treat hyperkalemia.
- All of the following are symptoms of TURP syndrome except:
a. lethargy
b. dysrhythmia
c. increased visual acuity
d. seizures
-c. increased visual acuity
Turp syndrome results from hyponatremia and hypervolemia. Symptoms include visual disturbances, muscle teitching, confusion, nausea and vomiting, restlessness, hypotension and arrhythmias.
- The corrrect size endotracheal tube for a 4 year old is:
a. 5
b. 4
c. 5.5
d. 4.5
- a. 5 The correct size is confirmed by easy passage and lack of air leak at low ventilationg pressure. Using the formula of the [(childs age/4) +4] would equal (4/4=)1 + 4>> 5
- In a 3 year old child, the endotracheal tube should be inserted to:
a. 13 cm
b. 14 cm
c. 15 cm
d. 12 cm
- 14 cm
Endotracheal tubes should be inserted to the midtracheal lposition, which for a 3 year old is approximately 14cm
[(age/2) +12]»_space; 3/2=1.5 +12=13.5 or 14
- All of the following are signs and symptoms of epiglottitis except:
a. inspiratory stridor
b. high fever
c. slow onset
d. drooling
-c. slow onset
Epiglotittis is characterized by a rapid onset of difficulties usually occuring within a 24 hour period
- The child with epiglottitis should be intubated:
a. in the operating room
b. in the emergency department
c. in the patient’s room
d. with fiberoptic instrumentation
- a. in the operating room
Usually intubation in the operating room is safer because emergency tracheostomy cam be performed easier. However, if acute airway management can be safely ensured in the emergency department, then intubation may proceed.
