WARNINGS
Included as part of the "PRECAUTIONS" Section
PRECAUTIONS
Malignant Hyperthermia
In susceptible individuals, potent inhalation anesthetic agents may trigger a skeletal muscle hypermetabolic state leading to high oxygen demand and the clinical syndrome
known as malignant hyperthermia. In genetically susceptible pigs, desflurane induced malignant hyperthermia. The clinical syndrome is signaled by hypercapnia, and may include muscle rigidity, tachycardia, tachypnea, cyanosis, arrhythmias, and/or unstable blood pressure. Some of these nonspecific signs may also appear during light anesthesia: acute hypoxia, hypercapnia, and hypovolemia.
Treatment of malignant hyperthermia includes discontinuation of triggering agents, administration of intravenous dantrolene sodium, and application of supportive therapy. (Consult prescribing information for dantrolene sodium intravenous for additional information on patient management.) Renal failure may appear later, and urine flow should be monitored and sustained if possible.
Fatal outcome of malignant hyperthermia has been reported with desflurane.
Perioperative Hyperkalemia
Use of inhaled anesthetic agents has been associated with rare increases in serum potassium levels that have resulted in cardiac arrhythmias and death in pediatric patients during the postoperative period. Patients with latent as well as overt neuromuscular disease, particularly Duchenne muscular dystrophy, appear to be most vulnerable. Concomitant use of succinylcholine has been associated with most, but not all, of these cases. These patients also experienced significant elevations in serum creatinine kinase levels and, in some cases, changes in urine consistent with myoglobinuria. Despite the similarity in presentation to malignant hyperthermia, none of these patients exhibited signs or symptoms of muscle rigidity or hypermetabolic state. Early and aggressive intervention to treat the hyperkalemia and resistant arrhythmias is recommended, as is subsequent evaluation for latent neuromuscular disease.
Respiratory Adverse Reactions In Pediatric Patients
SUPRANE is not approved for maintenance of anesthesia in non-intubated children due to an increased incidence of respiratory adverse reactions, including coughing, laryngospasm and secretions [see Clinical Studies].
Children, particularly if 6 years old or younger, who are under an anesthetic maintenance of SUPRANE delivered via laryngeal mask airway (LMA™ mask) are at increased risk for adverse respiratory reactions, e.g., coughing and laryngospasm, especially with removal of the laryngeal mask airway under deep anesthesia [see Clinical Studies]. Therefore, closely monitor these patients for signs and symptoms associated with laryngospasm and treat accordingly.
When SUPRANE is used for maintenance of anesthesia in children with asthma or a history of recent upper airway infection, there is an increased risk for airway narrowing and increases in airway resistance. Therefore, closely monitor these patients for signs and symptoms associated with airway narrowing and treat accordingly.
Interactions With Desiccated Carbon Dioxide Absorbents
Desflurane like some other inhalation anesthetics, can react with desiccated carbon dioxide (CO2) absorbents to produce carbon monoxide that may result in elevated levels of carboxyhemoglobin in some patients. Case reports suggest that barium hydroxide lime and soda lime become desiccated when fresh gases are passed through the CO2 canister at high flow rates over many hours or days. When a clinician suspects that CO2 absorbent may be desiccated, it should be replaced before the administration of SUPRANE.
Hepatobiliary Disorders
With the use of halogenated anesthetics, disruption of hepatic function, icterus and fatal liver necrosis have been reported; such reactions appear to indicate hypersensitivity. As with other halogenated anesthetic agents, SUPRANE may cause sensitivity hepatitis in patients who have been sensitized by previous exposure to halogenated anesthetics [see CONTRAINDICATIONS]. Cirrhosis, viral hepatitis or other pre-existing hepatic disease may be a reason to select an anesthetic other than a halogenated anesthetic. As with all halogenated anesthetics, repeated anesthesia within a short period of time should be approached with caution.
Pediatric Neurotoxicity
Published animal studies demonstrate that the administration of anesthetic and sedation drugs that block NMDA receptors and/or potentiate GABA activity increase neuronal apoptosis in the developing brain and result in long-term cognitive deficits when used for longer than 3 hours. The clinical significance of these findings is not clear. However, based on the available data, the window of vulnerability to these changes is believed to correlate with exposures in the third trimester of gestation through the first several months of life, but may extend out to approximately three years of age in humans. [See Use In Specific Populations , Nonclinical Toxicology].
Some published studies in children suggest that similar deficits may occur after repeated or prolonged exposures to anesthetic agents early in life and may result in adverse cognitive or behavioral effects. These studies have substantial limitations, and it is not clear if the observed effects are due to the anesthetic/sedation drug administration or other factors such as the surgery or underlying illness.
Anesthetic and sedation drugs are a necessary part of the care of children needing surgery, other procedures, or tests that cannot be delayed, and no specific medications have been shown to be safer than any other. Decisions regarding the timing of any elective procedures requiring anesthesia should take into consideration the benefits of the procedure weighed against the potential risks.
Laboratory Findings
Transient elevations in glucose and white blood cell count may occur as with use of other anesthetic agents.
Postoperative Agitation In Children
Emergence from anesthesia in children may evoke a brief state of agitation that may hinder cooperation.
Nonclinical Toxicology
Carcinogenesis, Mutagenesis, Impairment Of Fertility
Carcinogenesis
Long-term studies in animals to evaluate the carcinogenic potential of desflurane have not been conducted.
Mutagenesis
In vitro and in vivo genotoxicity studies did not demonstrate mutagenicity or chromosomal damage by desflurane. Tests for genotoxicity included the Ames mutation assay, the metaphase analysis of human lymphocytes, and the mouse micronucleus assay.
Impairment Of Fertility
In a study in which male animals were administered 8.2% desflurane (60% oxygen) for either 0.5, 1.0, or 4.0 hours per day beginning 63 days prior to mating and female animals were administered the same doses of desflurane for 14 days prior to mating through Lactation Day 21, there were no adverse effects on fertility in the
1.0 hour per day treatment group. However, reduced male and female fertility was noted in the 4 hour a day group. A dose dependent increase in mortality and decreased body weight gain was note in all treatment groups.
Use In Specific Populations
Pregnancy
Risk Summary
There are no adequate and well-controlled studies in pregnant women. In animal reproduction studies, embryo-fetal toxicity (reduced viable fetuses and/or increased post-implantation loss) was noted in pregnant rats and rabbits administered 1 MAC desflurane for 4 hours a day (4 MAC-hours/day) during organogenesis.
Published studies in pregnant primates demonstrate that the administration of anesthetic and sedation drugs that block NMDA receptors and/or potentiate GABA activity during the period of peak brain development increases neuronal apoptosis in the developing brain of the offspring when used for longer than 3 hours. There are no data on pregnancy exposures in primates corresponding to periods prior to the third trimester in humans [See Data].
The estimated background risk of major birth defects and miscarriage for the indicated population is unknown. All pregnancies have a background risk of birth defect, loss, or other adverse outcomes. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is 2-4% and 1520%, respectively.
Clinical Considerations
Labor or Delivery
The safety of SUPRANE during labor or delivery has not been demonstrated. SUPRANE is a uterine-relaxant.
Data
Animal Data
Pregnant rats were exposed to 8.2% desflurane (1 MAC; 60% oxygen) for 0.5, 1.0, or 4.0 hours (0.5, 1.0, or 4.0 MAC-hours) per day during organogenesis (Gestation Day 6-15).
Embryo-fetal toxicity (increased post-implantation loss and reduced viable fetuses) was noted in the 4 hour treatment group in the presence of maternal toxicity (reduced body weight gain). There was no evidence of malformations in any group.
Pregnant rabbits were exposed to 8.9% desflurane (1 MAC; 60% oxygen) for 0.5, 1.0, or
3.0 hours per day during organogenesis (Gestation Days 6-18). Fetal toxicity (reduced viable fetuses) was noted in the 3 hour treatment group in the presence of maternal toxicity (reduced body weight). There was no evidence of malformations in any group.
Pregnant rats were exposed to 8.2% desflurane (1 MAC; 60% oxygen) for 0.5, 1.0, or 4.0 hours per day from late gestation and through lactation (Gestation Day 15 to Lactation Day 21). Pup body weights were reduced in the 4 hours per day group in the presence of maternal toxicity (increased mortality and reduced body weight gain). This study did not evaluate neurobehavioral function including learning and memory or reproductive behavior in the first generation (F1) pups.
In a published study in primates, administration of an anesthetic dose of ketamine for 24 hours on Gestation Day 122 increased neuronal apoptosis in the developing brain of the fetus. In other published studies, administration of either isoflurane or propofol for 5 hours on Gestation Day 120 resulted in increased neuronal and oligodendrocyte apoptosis in the developing brain of the offspring. With respect to brain development, this time period corresponds to the third trimester of gestation in the human. The clinical significance of these findings is not clear; however, studies in juvenile animals suggest neuroapoptosis correlates with long-term cognitive deficits [See WARNINGS AND PRECAUTIONS, Pediatric Use and Nonclinical Toxicology].
Lactation
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when SUPRANE is administered to a nursing woman.
Pediatric Use
Respiratory Adverse Reactions In Pediatric Patients
SUPRANE is indicated for maintenance of anesthesia in infants and children after induction of anesthesia with agents other than SUPRANE, and tracheal intubation.
Is not approved for maintenance of anesthesia in non-intubated children due to an increased incidence of respiratory adverse reactions, including coughing (26%), laryngospasm (13%) and secretions (12%) [see Clinical Studies].
Children, particularly if 6 years old or younger, who are under an anesthetic maintenance of SUPRANE delivered via laryngeal mask airway (LMA™ mask) are at increased risk for adverse respiratory reactions, e.g., coughing and laryngospasm, especially with removal of the laryngeal mask airway under deep anesthesia [see Clinical Studies]. Therefore, closely monitor these patients for signs and symptoms associated with laryngospasm and treat accordingly.
When SUPRANE is used for maintenance of anesthesia in children with asthma or a history of recent upper airway infection, there is an increased risk for airway narrowing and increases in airway resistance. Therefore, closely monitor these patients for signs and symptoms associated with airway narrowing and treat accordingly.
Published juvenile animal studies demonstrate that the administration of anesthetic and sedation drugs, such as SUPRANE, that either block NMDA receptors or potentiate the activity of GABA during the period of rapid brain growth or synaptogenesis, results in widespread neuronal and oligodendrocyte cell loss in the developing brain and alterations in synaptic morphology and neurogenesis. Based on comparisons across species, the window of vulnerability to these changes is believed to correlate with exposures in the third trimester of gestation through the first several months of life, but may extend out to approximately 3 years of age in humans.
In primates, exposure to 3 hours of ketamine that produced a light surgical plane of anesthesia did not increase neuronal cell loss, however, treatment regimens of 5 hours or longer of isoflurane increased neuronal cell loss. Data from isoflurane-treated rodents and ketamine-treated primates suggest that the neuronal and oligodendrocyte cell losses are associated with prolonged cognitive deficits in learning and memory. The clinical significance of these nonclinical findings is not known, and healthcare providers should balance the benefits of appropriate anesthesia in pregnant women, neonates, and young children who require procedures with the potential risks suggested by the nonclinical data [See WARNINGS AND PRECAUTIONS, Pregnancy and Nonclinical Toxicology].
Geriatric Use
The minimum alveolar concentration (MAC) of SUPRANE decreases with increasing patient age. The dose should be adjusted accordingly. The average MAC for SUPRANE in a 70 year old patient is two-thirds the MAC for a 20 year old patient [see DOSAGE AND ADMINISTRATION Table 1 and Clinical Studies].
Renal Impairment
Concentrations of 1-4% SUPRANE in nitrous oxide/oxygen have been used in patients with chronic renal or hepatic impairment and during renal transplantation surgery.
Because of minimal metabolism, a need for dose adjustment in patients with renal and hepatic impairment is not to be expected.
Nine patients receiving desflurane (N=9) were compared to 9 patients receiving isoflurane, all with chronic renal insufficiency (serum creatinine 1.5-6.9 mg/dL). No differences in hematological or biochemical tests, including renal function evaluation, were seen between the two groups. Similarly, no differences were found in a comparison of patients receiving either desflurane (N=28) or isoflurane (N=30) undergoing renal transplant.
Hepatic Impairment
Eight patients receiving SUPRANE were compared to six patients receiving isoflurane, all with chronic hepatic disease (viral hepatitis, alcoholic hepatitis, or cirrhosis). No differences in hematological or biochemical tests, including hepatic enzymes and hepatic function evaluation, were seen.