Sevoflurane: uses, dosing, side effects & brands

Clinical Trials Experience Adverse events are derived from controlled clinical studies conducted in the United States, Canada, and Europe. The reference drugs were isoflurane, enflurane, and propofol in adults and halothane in pediatric patients. The studies were conducted using a variety of premedications, other anesthetics, and surgical procedures of varying length. Most adverse events reported were mild and transient, and may reflect the surgical procedures, patient characteristics (including disease) and/or medications administered. Of the 5182 patients enrolled in the clinical studies, 2906 were exposed to sevoflurane, including 118 adults and 507 pediatric patients who underwent mask induction. Each patient was counted once for each type of adverse event. Adverse events reported in patients in clinical studies and considered to be possibly or probably related to sevoflurane are presented within each body system in order of decreasing frequency in the following listings. One case of malignant hyperthermia was reported in pre-registration clinical studies. Adverse Events During the Induction Period (from Onset of Anesthesia by Mask Induction to Surgical Incision) Incidence > 1% Adult Patients (N = 118) Cardiovascular Bradycardia 5%, Hypotension 4%, Tachycardia 2% Nervous System Agitation 7% Respiratory System Laryngospasm 8%, Airway obstruction 8%, Breathholding 5%, Cough…

Known or suspected genetic susceptibility to malignant hyperthermia (see WARNINGS - Malignant Hyperthermia , CLINICAL PHARMACOLOGY - Pharmacogenomics ). Known or suspected sensitivity to sevoflurane or to other halogenated inhalational anesthetics.

In clinical studies, no significant adverse reactions occurred with other drugs commonly used in the perioperative period, including central nervous system depressants, autonomic drugs, skeletal muscle relaxants, anti-infective agents, hormones and synthetic substitutes, blood derivatives, and cardiovascular drugs. Epinephrine Epinephrine administered with sevoflurane may increase the risk of ventricular arrhythmias. Monitor the electrocardiogram and blood pressure and ensure emergency medications to treat ventricular arrhythmias are readily available. Calcium antagonists Sevoflurane may lead to marked hypotension in patients treated with calcium antagonists. Blood pressure should be closely monitored and emergency medications to treat hypotension should be readily available when calcium antagonists are used concomitantly with sevoflurane. In animals, impairment of atrioventricular conduction has been observed when verapamil and sevoflurane are administered concomitantly. Succinylcholine See WARNINGS - Perioperative Hyperkalemia . Non-selective MAO-inhibitors Concomitant use of MAO inhibitors and inhalational anesthetics may increase the risk of hemodynamic instability during surgery or medical procedures. Intravenous Anesthetics Sevoflurane administration is compatible with barbiturates, propofol, and other commonly used intravenous anesthetics. Benzodiazepines and Opioids Benzodiazepines and opioids would be expected to decrease the MAC of sevoflurane in the same manner as with other inhalational anesthetics. Sevoflurane administration is compatible with benzodiazepines and opioids as commonly used in surgical practice. Nitrous Oxide As with other halogenated volatile anesthetics, the anesthetic requirement for sevoflurane is decreased when administered in combination with nitrous oxide. Using 50% N 2 O, the MAC equivalent dose requirement is reduced approximately 50% in adults, and approximately 25% in pediatric patients (see DOSAGE AND ADMINISTRATION ). Neuromuscular Blocking Agents As is the case with other volatile anesthetics, sevoflurane increases both the intensity and duration of neuromuscular blockade induced by nondepolarizing muscle relaxants. When used to supplement alfentanil-N 2 O anesthesia, sevoflurane and isoflurane equally potentiate neuromuscular block induced with pancuronium, vecuronium or atracurium. Therefore, during sevoflurane anesthesia, the dosage adjustments for these muscle relaxants are similar to those required with isoflurane. Potentiation of neuromuscular blocking agents requires equilibration of muscle with delivered partial pressure of sevoflurane. Reduced doses of neuromuscular blocking agents during induction of anesthesia may result in delayed onset of conditions suitable for endotracheal intubation or inadequate muscle relaxation. Among available nondepolarizing agents, only vecuronium, pancuronium and atracurium interactions have been studied during sevoflurane anesthesia. In the absence of specific guidelines: For endotracheal intubation, do not reduce the dose of nondepolarizing muscle relaxants. During maintenance of anesthesia, the required dose of nondepolarizing muscle relaxants is likely to be reduced compared to that during N 2 O/opioid anesthesia. Administration of supplemental doses of muscle relaxants should be guided by the response to nerve stimulation. The effect of sevoflurane on the duration of depolarizing neuromuscular blockade induced by succinylcholine has not been studied.