Sevoflurane (Ultane)

Anesthesia Implications

Classification: Volatile inhalation anesthetic
Therapeutic Effects: Inhalation anesthesia, inducing and maintaining anesthesia.
Time to Onset: Dose dependent – for 1.8 MAC Sevoflurane + 66% N2O it takes approximately 1.6 minutes to achieve a loss of eyelid reflex.
Time to Peak: Dose-dependent; usually reaches peak sedation levels quickly due to low blood/gas solubility.
Duration: Short duration, with rapid emergence due to low fat/blood partition coefficient, allowing fast elimination post-administration.

Contraindications

Known or suspected genetic susceptibility to malignant hyperthermia.

Primary Considerations

Malignant Hyperthermia – Assess patient history for susceptibility, as sevoflurane can trigger this condition.

Compound A – The manufacturer advises maintaining flow rates above 2 L/min to minimize the risk of nephrotoxic Compound A production. However, the ASA supports flow rates as low as 0.5 L/min, stating this is sufficient for most adult patients and reduces excessive anesthetic waste.

Emissions and Waste – Consider keeping the anesthetic fresh gas flows low (as stated above). Operating rooms account for 30% of greenhouse gas (GHG) contributors.

Side Effects –  Causes dose-dependent respiratory depression and reduced blood pressure due to peripheral vasodilation. Minimal effect on heart rate.

Uterine contractility – Sevoflurane reduces uterine contractility.

MAC – The MAC for sevoflurane in elderly patients is 1.5%, which is lower than the MAC for children (2.5%) and adults (1.7–2.0%).

Reversal

No direct reversal; Effects wear off rapidly after cessation of inhalation due to its low solubility and high rate of pulmonary elimination.

Method of Action

Acts by enhancing inhibitory neurotransmission and reducing excitatory neurotransmission in the CNS, leading to loss of consciousness and sensation.

Metabolism

Hepatic

Elimination

Pulmonary, hepatic, and renal.