Inhalation anesthetics – Desflurane MCQs With Answer

Inhalation anesthetics – Desflurane MCQs With Answer

Desflurane is a widely used volatile inhalation anesthetic notable for rapid induction and emergence, low blood-gas solubility, and minimal metabolism. This concise, Student-friendly post covers key B. Pharm concepts: physicochemical properties, mechanism of action, pharmacokinetics, equipment (heated vaporizers), clinical applications, adverse effects (airway irritation, tachycardia, malignant hyperthermia risk), environmental impact, and comparisons with sevoflurane and isoflurane. Understanding desflurane’s MAC, blood-gas partition coefficient, and safety profile helps pharmacy students advise clinicians and counsel on perioperative drug interactions and organ-specific risks. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. Which property of desflurane primarily explains its very rapid induction and emergence?

• High oil-gas partition coefficient
• High blood-gas partition coefficient
• Low blood-gas partition coefficient
• High solubility in tissues

Correct Answer: Low blood-gas partition coefficient

Q2. Desflurane is most appropriately described as:

• An intravenous anesthetic
• A volatile inhalation anesthetic
• A local anesthetic
• A neuromuscular blocker

Correct Answer: A volatile inhalation anesthetic

Q3. Compared to sevoflurane, desflurane has:

• Higher blood-gas solubility
• Lower blood-gas solubility
• Greater degree of hepatic metabolism
• Lower vapor pressure

Correct Answer: Lower blood-gas solubility

Q4. Which clinical advantage is most associated with desflurane in ambulatory surgery?

• Longer postoperative analgesia
• Faster recovery and emergence
• Stronger muscle relaxation
• Greater potency allowing lower concentrations

Correct Answer: Faster recovery and emergence

Q5. The minimum alveolar concentration (MAC) is a measure of:

• Cardiovascular depression caused by an anesthetic
• Potency required to prevent movement in 50% of patients
• Metabolic clearance of the anesthetic by the liver
• Degree of airway irritation

Correct Answer: Potency required to prevent movement in 50% of patients

Q6. Desflurane’s blood-gas partition coefficient is best described as:

• Very high (>>1), causing slow induction
• Approximately 0.42, causing rapid kinetics
• Equal to oil-gas coefficient
• Zero, indicating no blood solubility

Correct Answer: Approximately 0.42, causing rapid kinetics

Q7. Which statement about desflurane metabolism is correct?

• It is extensively metabolized by the liver (>50%)
• It undergoes negligible metabolism (<0.1%)
• It is converted to active metabolites that provide analgesia
• It is metabolized primarily to halothane-like products

Correct Answer: It undergoes negligible metabolism (<0.1%)

Q8. A practical equipment requirement unique to desflurane is:

• Use of a cold vaporizer
• Use of a heated, pressurized vaporizer
• No vaporizer is required
• Use of syringe pump for delivery

Correct Answer: Use of a heated, pressurized vaporizer

Q9. The primary mechanism by which desflurane produces anesthesia is believed to involve:

• Agonism at opioid receptors
• Enhancement of inhibitory GABA-A and glycine receptor activity
• Competitive antagonism at nicotinic receptors
• Direct blockade of voltage-gated sodium channels

Correct Answer: Enhancement of inhibitory GABA-A and glycine receptor activity

Q10. Which adverse effect is commonly associated with rapid increases in desflurane concentration?

• Profound bradycardia without hypertension
• Airway irritation with coughing and laryngospasm
• Severe renal failure due to fluoride production
• Prolonged neuromuscular blockade

Correct Answer: Airway irritation with coughing and laryngospasm

Q11. Desflurane is relatively contraindicated in patients susceptible to:

• Neuroleptic malignant syndrome
• Malignant hyperthermia
• Immediate-type hypersensitivity to penicillin
• Myasthenia gravis

Correct Answer: Malignant hyperthermia

Q12. Which environmental concern is most significant for desflurane?

• Ozone layer depletion is high
• Minimal greenhouse warming potential
• High global warming potential compared to other anesthetics
• No environmental impact because it degrades rapidly

Correct Answer: High global warming potential compared to other anesthetics

Q13. The vaporizer used for desflurane must be heated because:

• Desflurane is solid at room temperature
• It has a high vapor pressure near room temperature
• It decomposes at room temperature
• Heating reduces its potency

Correct Answer: It has a high vapor pressure near room temperature

Q14. Compared to isoflurane, desflurane typically causes:

• Slower emergence
• More pronounced airway irritation
• Greater hepatic metabolism
• Stronger analgesic effect

Correct Answer: More pronounced airway irritation

Q15. Which monitoring parameter best reflects anesthetic depth for inhalational agents like desflurane?

• End-tidal anesthetic concentration
• Serum anesthetic concentration
• Urinary fluoride levels
• ECG QRS duration

Correct Answer: End-tidal anesthetic concentration

Q16. Which patient factor increases the speed of induction with desflurane?

• High cardiac output
• Low alveolar ventilation
• Low blood solubility of the agent
• High tissue solubility

Correct Answer: Low blood solubility of the agent

Q17. Desflurane’s effect on systemic circulation at high concentrations often includes:

• Marked decrease in systemic vascular resistance and tachycardia
• Severe coronary vasospasm
• Profound increase in systemic vascular resistance with bradycardia
• No hemodynamic effects

Correct Answer: Marked decrease in systemic vascular resistance and tachycardia

Q18. Which statement about desflurane and renal toxicity is correct?

• Desflurane produces high levels of nephrotoxic fluoride metabolites
• Desflurane has negligible hepatic metabolism, resulting in low fluoride generation
• Desflurane causes irreversible renal failure in most patients
• Desflurane is contraindicated in all renal impairment

Correct Answer: Desflurane has negligible hepatic metabolism, resulting in low fluoride generation

Q19. The term MAC-awake refers to:

• Concentration that produces immobility in 50% of patients
• Concentration at which 50% of patients respond to verbal command
• Concentration causing apnea in 50% of patients
• Serum concentration required for analgesia

Correct Answer: Concentration at which 50% of patients respond to verbal command

Q20. For inhalational induction in a fearful pediatric patient, desflurane is less suitable because it:

• Has a pleasant odor that calms children
• Is highly soluble, causing slow induction
• Is an airway irritant producing breath-holding and coughing
• Causes long-lasting sedation

Correct Answer: Is an airway irritant producing breath-holding and coughing

Q21. The alveolar concentration to inspired concentration ratio (FA/FI) rises faster with desflurane because of:

• High tissue solubility
• Low potency
• Low blood-gas partition coefficient
• Extensive hepatic metabolism

Correct Answer: Low blood-gas partition coefficient

Q22. Which of the following best describes desflurane’s oil-gas partition coefficient relative to potency?

• High oil-gas coefficient correlates with high potency
• Oil-gas coefficient is unrelated to potency
• Low oil-gas coefficient means higher potency
• Oil-gas coefficient only affects metabolism

Correct Answer: High oil-gas coefficient correlates with high potency

Q23. Which drug interaction is important to consider with desflurane?

• Synergistic CNS depression with benzodiazepines and opioids
• Antagonism with propofol reducing anesthetic depth
• Activation of CYP450 causing increased desflurane clearance
• Complete inactivation by cholinesterases

Correct Answer: Synergistic CNS depression with benzodiazepines and opioids

Q24. Which of the following anesthetic effects is least likely with desflurane?

• Analgesia at surgical levels
• Hypnosis and amnesia
• Skeletal muscle relaxation through central action
• Complete analgesia similar to opioids

Correct Answer: Complete analgesia similar to opioids

Q25. Occupational exposure concerns for desflurane emphasize:

• Ensuring scavenging systems to minimize waste gas exposure
• Using open-circuit anesthesia to vent gases to OR
• No need for monitoring air quality due to low vapor pressure
• Switching vaporizers every 10 minutes

Correct Answer: Ensuring scavenging systems to minimize waste gas exposure

Q26. Which physical property of desflurane makes its delivery device different from other volatile agents?

• Extremely low molecular weight
• Solid crystalline form at 25°C
• Very high saturated vapor pressure at room temperature
• Complete miscibility with propofol

Correct Answer: Very high saturated vapor pressure at room temperature

Q27. Which patient condition would most likely prolong emergence from desflurane anesthesia?

• Increased alveolar ventilation
• Obesity with large tissue reservoirs of anesthetic
• Low cardiac output
• Use of desflurane alone without opioids

Correct Answer: Obesity with large tissue reservoirs of anesthetic

Q28. Which statement about desflurane and cerebral physiology is true?

• It decreases cerebral blood flow at clinical concentrations
• It increases cerebral blood flow and intracranial pressure at higher concentrations
• It has no effect on cerebral metabolic rate
• It causes permanent neuronal damage

Correct Answer: It increases cerebral blood flow and intracranial pressure at higher concentrations

Q29. Which monitoring change indicates inadequate alveolar washout of desflurane at the end of surgery?

• Rapid fall in end-tidal concentration
• Sustained elevated end-tidal concentration despite discontinuation
• Immediate return of airway reflexes
• Stable MAC value of zero

Correct Answer: Sustained elevated end-tidal concentration despite discontinuation

Q30. Desflurane is most suitable for which type of procedure?

• Short ambulatory procedures requiring rapid recovery
• Long procedures where slow emergence is preferable
• Procedures requiring deep postoperative analgesia
• Cases where sevoflurane is absolutely required due to airway reactivity

Correct Answer: Short ambulatory procedures requiring rapid recovery

Q31. Which inhalational anesthetic property correlates inversely with speed of onset?

• Low MAC
• High blood-gas partition coefficient
• Low vapor pressure
• High alveolar ventilation

Correct Answer: High blood-gas partition coefficient

Q32. In the context of pharmacokinetics, desflurane demonstrates which pattern of distribution?

• Predominantly tissue binding with slow redistribution
• Rapid equilibration between alveolar gas and blood
• Extensive accumulation in adipose tissue with no elimination
• Primary elimination via renal tubular secretion

Correct Answer: Rapid equilibration between alveolar gas and blood

Q33. The primary elimination route for unchanged desflurane is:

• Renal excretion of unchanged drug
• Exhalation via the lungs
• Hepatic biotransformation to active metabolites
• Sequestration in bone

Correct Answer: Exhalation via the lungs

Q34. When switching from desflurane to sevoflurane intraoperatively, which consideration is important?

• No need to adjust for airway irritation
• Be aware of different MAC values and adjust concentrations accordingly
• Desflurane and sevoflurane have identical hemodynamic profiles
• Both use the same heated vaporizer settings

Correct Answer: Be aware of different MAC values and adjust concentrations accordingly

Q35. Which laboratory marker may be monitored when concerned about volatile anesthetic metabolism?

• Plasma creatine kinase for muscle damage
• Serum fluoride levels when using metabolized volatile agents
• Serum amylase for pancreatic injury
• Platelet count for coagulopathy

Correct Answer: Serum fluoride levels when using metabolized volatile agents

Q36. In patients with severe hepatic impairment, desflurane is often preferred because:

• It is extensively metabolized by the liver
• It has minimal hepatic metabolism and limited dependence on liver for elimination
• It enhances hepatic blood flow dramatically
• It binds irreversibly to hepatic proteins

Correct Answer: It has minimal hepatic metabolism and limited dependence on liver for elimination

Q37. Which perioperative benefit of desflurane is relevant to elderly patients?

• Slower emergence leading to better postoperative cognition
• Rapid emergence which may reduce prolonged sedation
• Complete prevention of postoperative delirium
• No impact on postoperative recovery times

Correct Answer: Rapid emergence which may reduce prolonged sedation

Q38. The use of desflurane in laparoscopic surgery may require attention to:

• Increased intracranial pressure due to CO2 insufflation
• Complete protection against airway reactivity
• Guaranteed absence of hemodynamic changes
• Inability to monitor end-tidal gas

Correct Answer: Increased intracranial pressure due to CO2 insufflation

Q39. Which statement about desflurane-induced tachycardia is accurate?

• Tachycardia is unrelated to desflurane concentration changes
• Rapid increases in concentration can produce sympathetic stimulation and tachycardia
• Desflurane consistently causes bradycardia only
• Tachycardia is due to direct beta-adrenergic agonism

Correct Answer: Rapid increases in concentration can produce sympathetic stimulation and tachycardia

Q40. Which best practice reduces airway irritation when using desflurane?

• Rapidly increasing inspired concentration during induction
• Using slow incremental increases and administering opioids or lidocaine
• Delivering 100% desflurane for induction
• Avoiding use of IV induction agents

Correct Answer: Using slow incremental increases and administering opioids or lidocaine

Q41. Desflurane’s effect on uterine tone is important in obstetric anesthesia because it:

• Strongly increases uterine tone, promoting contractility
• Can cause dose-dependent uterine relaxation and bleeding
• Has no effects on uterine smooth muscle
• Is the preferred agent for maintaining uterine contraction

Correct Answer: Can cause dose-dependent uterine relaxation and bleeding

Q42. Which measure best minimizes environmental release of desflurane?

• Use of low-flow anesthesia and effective scavenging systems
• Delivering agent with open scavenging into OR atmosphere
• Using multiple vaporizers simultaneously
• Increasing fresh gas flow to dilute waste gases

Correct Answer: Use of low-flow anesthesia and effective scavenging systems

Q43. Which of the following is an accurate statement about desflurane’s MAC in relation to age?

• MAC increases with age
• MAC decreases with increasing age
• MAC remains constant across all ages
• MAC is irrelevant for desflurane

Correct Answer: MAC decreases with increasing age

Q44. When comparing emergence from desflurane to isoflurane after long procedures, desflurane typically shows:

• Slower emergence due to higher tissue solubility
• Faster emergence because of lower solubility
• No difference in emergence times
• Greater postoperative nausea requiring routine antiemetics

Correct Answer: Faster emergence because of lower solubility

Q45. Which precaution is necessary when using desflurane in patients with significant cardiovascular disease?

• Expect no hemodynamic effects and proceed without monitoring
• Monitor hemodynamics closely due to potential hypotension and tachycardia
• Avoid all co-administered opioids
• Increase MAC by 50% to maintain stability

Correct Answer: Monitor hemodynamics closely due to potential hypotension and tachycardia

Q46. Which statement about desflurane’s effect on respiratory drive is correct?

• It stimulates respiration at anesthetic concentrations
• It causes dose-dependent respiratory depression and reduced tidal volume
• It has no effect on ventilation
• It selectively increases respiratory rate without affecting tidal volume

Correct Answer: It causes dose-dependent respiratory depression and reduced tidal volume

Q47. Which of the following is true regarding the use of desflurane during neurosurgery?

• Desflurane is always preferred due to no effect on intracranial pressure
• High concentrations may increase intracranial pressure; use cautiously
• It permanently reduces cerebral metabolic rate without hemodynamic effects
• It eliminates the need for neuromonitoring

Correct Answer: High concentrations may increase intracranial pressure; use cautiously

Q48. Which statement about desflurane and postoperative nausea and vomiting (PONV) is accurate?

• Volatile agents including desflurane are associated with increased PONV risk
• Desflurane completely prevents PONV
• PONV is unrelated to anesthetic choice
• Desflurane guarantees less PONV than propofol even in high-risk patients

Correct Answer: Volatile agents including desflurane are associated with increased PONV risk

Q49. In an operating room with limited scavenging, which is the best anesthetic practice concerning desflurane?

• Prefer alternative agents with lower global warming potential and reduce fresh gas flow
• Use maximum fresh gas flow to dilute workplace concentration
• Use multiple desflurane vaporizers for redundancy
• Operate without monitoring occupational exposure

Correct Answer: Prefer alternative agents with lower global warming potential and reduce fresh gas flow

Q50. Which statement correctly summarizes desflurane’s clinical profile?

• High potency, slow emergence, extensive metabolism
• Low blood solubility, rapid recovery, airway irritant, minimal metabolism
• Ideal for inhalational induction in children due to no airway effects
• Primary intravenous anesthetic used for long-term sedation

Correct Answer: Low blood solubility, rapid recovery, airway irritant, minimal metabolism

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com