27 questions match your search.
A 46-year-old patient who abuses intravenous drugs develops acute aortic valvular insufficiency from bacterial endocarditis. Which of the following statements concerning pressures measured through a pulmonary artery catheter is true?
- (A) Pulmonary artery occlusion pressure will underestimate left ventricular end-diastolic pressure
- (B) Pulmonary artery oxygen saturation will overestimate mixed venous oxygen saturation
- (C) Thermodilution cardiac output determination will overestimate cardiac output
- (D) Right ventricular end-diastolic pressure will equal left ventricular end-diastolic pressure
- (E) The pulmonary artery occlusion pressure trace will most likely have large V waves
A 75-year-old man with a left bundle branch block is undergoing placement of a pulmonary artery catheter through the right internal jugular vein. He becomes pale and his heart rate decreases to 40 bpm when the catheter tip enters the right ventricle. The most likely cause is
- (A) a catheter loop in the right atrium
- (B) acute myocardial infarction
- (C) acute pneumothorax
- (D) carotid sinus reflex
- (E) complete heart block
Pulmonary artery occlusion pressure
- (A) does not reliably reflect left ventricular end-diastolic volume when left ventricular compliance is reduced
- (B) inaccurately reflects left atrial pressure when left atrial pressure exceeds 15 mmHg
- (C) is measured at end-inspiration in mechanically ventilated patients
- (D) overestimates left atrial pressure in patients with poor lung compliance
- (E) reflects left atrial pressure only if the catheter tip is located in zone II of the lung
During laser excision of vocal cord polyps in a 5-year-old boy, dark smoke suddenly appears in the surgical field. The trachea is intubated and anesthesia is being maintained with halothane, nitrous oxide, and oxygen. The most appropriate initial step is to
- (A) change from oxygen and nitrous oxide to air
- (B) fill the oropharynx with water
- (C) instill water into the endotracheal tube
- (D) remove the endotracheal tube
- (E) ventilate with carbon dioxide
The risk for airway fire during laser resection of a tracheal tumor is decreased by use of
- (A) a CO2 laser rather than a YAG laser
- (B) an inspired helium concentration greater than 60%
- (C) an inspired nitrous oxide concentration greater than 60%
- (D) a polyvinylchloride endotracheal tube
- (E) halothane in the inspired mixture
A 32-year-old woman is anesthetized for suboccipital craniotomy. During positioning, the capnograph shows an abrupt decrease in the slope of the expiratory upstroke. Which of the following is the most likely cause?
- (A) Air embolism
- (B) Incompetent expiratory valve
- (C) Incomplete neuromuscular block
- (D) Kinked endotracheal tube
- (E) Tracheal extubation
A child undergoing general anesthesia is breathing spontaneously using the Jackson-Rees modification of the Ayres T-piece. Respiratory rate is 20/min and tidal volume is 75 ml. What is the minimum fresh gas flow required to prevent rebreathing?
- (A) 750 ml/min
- (B) 1500 ml/min
- (C) 2250 ml/min
- (D) 4500 ml/min
- (E) 6000 ml/min
A neurologically intact 48-year-old woman is scheduled for removal of a parietal lobe arteriovenous malformation. The relative risk for complete resection is to be determined by a test occlusion of the feeding artery. Which of the following intraoperative monitoring techniques is most appropriate for this test?
- (A) Brain stem auditory evoked potentials
- (B) Cerebral blood flow using radioactive xenon
- (C) EEG
- (D) Evoked potentials elicited by stimulating the posterior tibial nerve
- (E) Transcranial Doppler
The jet ventilation technique using an injector during laryngobronchoscopy relies on
- (A) air entrainment
- (B) relative density of inhaled gases
- (C) presence of an endotracheal tube
- (D) presence of spontaneous ventilation
- (E) use of helium-oxygen mixtures
An arterial blood sample is obtained from a patient undergoing hypothermic cardiopulmonary bypass at 28 C. Analysis at 37 C shows a pH of 7.40 and PaCO2 of 40 mmHg. Which of the following values are most likely if the analysis is corrected to 28 C?
- (A) pH = 7.40; PaCO2 = 40
- (B) pH > 7.40; PaCO2 < 40
- (C) pH > 7.40; PaCO2 > 40
- (D) pH < 7.40; PaCO2 < 40
- (E) pH < 7.40; PaCO2 > 40
A multi-orifices right heart catheter is being positioned by EKG control prior to sitting craniotomy. The EKG tracing is obtained between the distal tip of the catheter and the right arm lead. The most appropriate next step is to
- (A) leave the catheter in place
- (B) advance the catheter 2 to 3 cm
- (C) withdraw the catheter 2 to 3 cm
- (D) remove the catheter completely
- (E) change polarity of the EKG
Pulmonary artery diastolic pressure is an unreliable indicator of left ventricular end-diastolic pressure in patients with
- (A) acute cardiogenic pulmonary edema
- (B) aortic stenosis
- (C) acute mitral regurgitation
- (D) myocardial ischemia
- (E) severe emphysema
The most sensitive means of detecting venous air embolism is
- (A) precordial Doppler stethoscope
- (B) transesophageal echocardiography
- (C) end-tidal carbon dioxide measurement
- (D) pulmonary artery pressure measurement
- (E) central venous pressure measurement
The principal rationale for the use of warmed humidified inspired anesthetic gases in children is to
- (A) decrease postoperative respiratory complications
- (B) decrease postoperative shivering
- (C) preserve ciliary function
- (D) prevent dehydration
- (E) prevent evaporative heat loss
A pulmonary artery catheter is placed in an awake patient breathing room air. Typical right ventricular and pulmonary artery pressure tracings are obtained. With the catheter balloon inflated, blood drawn from the distal port has a PaO2 of 100 mmHg, while a simultaneous radial artery sample has a PaO2 of 90 mmHg. These data indicate that the
- (A) shunt fraction is greater than 10%
- (B) catheter is in the wedged position
- (C) catheter has entered a pulmonary vein
- (D) cardiac output is abnormally high
- (E) oxygen electrode is malfunctioning
A healthy 57-year-old man with a ureteral calculus is scheduled for immersion extracorporeal shock wave lithotripsy. Which of the following statements is true?
- (A) Delivery of the shock wave is timed by the R wave of the ECG
- (B) Continuous epidural anesthesia is contraindicated because of the risk for infection
- (C) If a regional technique is used, a T10 sensory level is required for adequate anesthesia
- (D) If general anesthesia is used, high tidal volumes and low respiratory rate are preferred
- (E) Removal of the patient from the bath is accompanied by an increase in blood pressure
Which of the following detects the smallest volume of venous air embolization?
- (A) Changing the precordial Doppler ultrasound signal
- (B) Decreasing PetC02
- (C) Decreasing Sp02
- (D) Increasing central venous pressure
- (E) Increasing pulmonary artery pressure
During laser excision of a vocal cord polyp, the tracheal tube ignites. Which of the following is the most appropriate next step?
- (A) Continue ventilation with air
- (B) Ensure patency of the endotracheal tube
- (C) Extubate the trachea
- (D) Flood the surgical field with saline solution
- (E) Increase the concentration of nitrous oxide
After the bronchial and tracheal cuffs of a right endobronchial tube are inflated, ventilation through the tracheal lumen is not possible. This finding is most consistent with
- (A) cuff occlusion of the right upper lobe bronchus
- (B) intubation of the left bronchus
- (C) left-sided tension pneumothorax
- (D) overinflation of the bronchial cuff
- (E) positioning of both cuffs in the trachea
Intraoperatively, the occurrence of prominent "a" waves on the central venous pressure waveform can be explained by each of the following EXCEPT
- (A) acute right ventricular failure
- (B) atrial flutter
- (C) complete heart block
- (D) onset of junctional tachycardia
- (E) ventricular pacing
During induction of general anesthesia in a patient with a supraglottic tumor, both intubation and subsequent ventilation via a face mask are impossible. A cricothyroidotomy is performed with a 16-gauge intravenous catheter. Which of the following statements is true?
- (A) Application of pressures greater than 35 cmH2O to the catheter will increase the risk for pulmonary barotrauma
- (B) PaC02 can be maintained at a normal level using a standard circle system attached to the catheter
- (C) PaO2 greater than 100 mmHg can be maintained indefinitely using transtracheal jet ventilation with pure oxygen through the catheter
- (D) Emergency surgical tracheostomy would have improved the likelihood of survival
- (E) The presence of this tumor contraindicates jet ventilation via cricothyroidotomy
Reduction of fire hazards during laser surgery of the airway is best accomplished by use of
- (A) continuous mode laser emissions
- (B) a nitrous oxide/opioid/relaxant anesthetic technique
- (C) a polyvinylchloride endotracheal tube and cuff
- (D) topical lidocaine
- (E) saline-filled sponges over exposed tissues
An otherwise healthy 16-year-old girl is undergoing posterior spinal fusion for thoracolumbar scoliosis. During the procedure, the most likely cause of a marked decrease in the amplitude of the somatosensory evoked potentials after stimulation of the posterior tibial nerve is
- (A) administration of fentanyl 30 jag /kg for induction
- (B) administration of isoflurane 1.3 MAC for maintenance
- (C) administration of vecuronium 0.15 mg/kg
- (D) a decrease in body temperature from 37 to 35°C
- (E) a decrease in cerebrospinal fluid pressure
In a 5-kg child, the end-tidal carbon dioxide tension is 35 mmHg during spontaneous ventilation through a Mapleson D system. Which single change is most likely to increase this value?
- (A) Decreasing the fresh gas flow
- (B) Increasing respiratory minute volume
- (C) Opening the pressure release valve
- (D) Removing the reservoir bag
- (E) Substituting larger bore tubing
Cardiac output measured by thermodilution with a pulmonary artery catheter most accurately reflects systemic blood flow in a patient with
- (A) aortic regurgitation
- (B) atrial septal defect
- (C) patent ductus arteriosus
- (D) tricuspid insufficiency
- (E) ventricular septal defect
A 2-year-old child has cardiac arrest during an inguinal herniorrhaphy under general anesthesia administered during a Jackson-Rees system. The graph shows end-tidal PCO2 monitored from the tip of the endotracheal tube during cardiopulmonary resuscitation; minute ventilation is unchanged. Which of the following is the most likely cause of the change beginning at the arrow?
- (A) Decreased fresh gas flow
- (B) Inadequate chest compression
- (C) Increased dead space
- (D) Restoration of cardiac output
- (E) Sampling artifact
A 5-year-old boy is to undergo microlaryngeal carbon dioxide laser vaporization of laryngotracheal papillomas under halothane administered through a small polyvinylchloride (PVC) endotracheal tube. The diluent gas mixture LEAST likely to support laser combustion of the PVC tube is
- (A) oxygen 40%, nitrous oxide 60%
- (B) oxygen 25%, nitrous oxide 75%
- (C) oxygen 30%, nitrogen 70%
- (D) oxygen 30%, helium 70%
- (E) oxygen 30%, air 70%