Latest Inhalation Anesthetic
Sevoflurane is the most recent widely-adopted inhalation anesthetic agent, approved by the FDA and currently considered the standard of care for both induction and maintenance of general anesthesia in adults and children. 1
Why Sevoflurane is the Current Standard
Sevoflurane represents the closest approximation to an "ideal" inhalation anesthetic among currently available agents, with properties that prioritize patient safety and optimal outcomes 2:
- Low blood:gas partition coefficient (0.63-0.69) enables rapid induction and emergence, reducing time under anesthesia and improving recovery quality 1, 3
- Non-pungent odor with minimal airway irritation makes it uniquely suitable for mask induction in adults, unlike isoflurane which causes significant coughing and breath-holding 4, 5
- Minimal cardiovascular depression compared to older agents, maintaining hemodynamic stability 6
- Rapid reversibility allows quick return to spontaneous ventilation if airway management fails, a critical safety feature 4
Clinical Superiority Over Alternatives
Sevoflurane demonstrates faster recovery times than isoflurane and comparable or superior recovery to propofol 1:
- Time to emergence: 8-11 minutes with sevoflurane vs. 13-16 minutes with isoflurane 1
- Time to respond to commands: 9-13 minutes with sevoflurane vs. 11-18 minutes with isoflurane 1
- Patients experience less clumsiness and confusion during recovery compared to isoflurane 5
Guideline-Recommended Applications
Multiple international anesthesia societies specifically recommend sevoflurane as a hypnotic of choice 4:
- For anticipated difficult intubation: Sevoflurane with propofol are the recommended rapidly reversible agents to optimize mask ventilation and intubation conditions while maintaining the ability to restore spontaneous breathing 4
- For life-threatening asthma: Sevoflurane and isoflurane have direct bronchodilator effects and are recommended for patients unresponsive to maximal conventional therapy 4
- For mask induction: Sevoflurane's lack of airway irritation makes it superior to all other volatile agents for inhalation induction 1, 7
Dosing for Average Adults
The minimum alveolar concentration (MAC) for a 40-year-old adult is 2.1% in oxygen 1:
- MAC decreases with age, requiring dose adjustment in elderly patients 1
- Induction typically uses 5.0% sevoflurane in oxygen or oxygen/nitrous oxide mixture 5
- Maintenance concentrations average 0.64-1.43 MAC-hours depending on surgical duration 1
Safety Profile
Sevoflurane has an established safety record with minimal organ toxicity concerns 2, 6:
- Lower hepatotoxicity potential than halothane 6
- Despite elevated plasma fluoride levels from metabolism, no fluoride-induced nephrotoxicity has been observed in humans 6, 3
- Degradation by CO2 absorbents produces compound A, but clinical nephrotoxicity has not been demonstrated 4, 3
Environmental Considerations
While sevoflurane has greenhouse gas emissions, clinical practice should prioritize patient safety over environmental concerns when both cannot be optimized simultaneously 4:
- Environmental optimization strategies (low fresh gas flows of 2-3 L/min) can reduce carbon footprint without compromising clinical effectiveness 4, 7
- The choice between sevoflurane and total intravenous anesthesia (TIVA) should be based primarily on patient history, pharmacology, and clinical needs 4
Common Pitfalls to Avoid
- Do not use sevoflurane as first-line in full-stomach patients requiring rapid sequence induction—its slower onset compared to intravenous agents makes it inappropriate when aspiration risk is high 4
- Do not exceed fresh gas flows unnecessarily—flows of 2-3 L/min are adequate for maintenance and reduce both cost and environmental impact 7, 3
- Do not assume all volatile agents are interchangeable—sevoflurane's unique non-pungent properties make it specifically superior for mask induction compared to isoflurane or desflurane 5