What is Sevoflurane?

Sevoflurane is a volatile, non-flammable, and highly fluorinated methyl isopropyl ether anesthetic agent used to induce and maintain general anesthesia in patients or lab animals.[1]

Chemical structure of Sevoflurane

Figure: Chemical structure of Sevoflurane.[1]

General anesthesia is a combination of drugs used during surgeries, medical procedures, or dissection of live animals in lab experiments to create a sleep-like state.[2] The anesthesia induces the patients or lab animals into a coma, resulting in loss of proactive reflexes for a painless procedure.[2]

Anesthesia can be induced intravenously by delivering drugs via injection or inhalation. Sevoflurane is a type of inhalation anesthetic agents delivered through a laryngeal mask, face mask airway, or tracheal tube attached to an anesthetic vaporizer and an anesthetic delivery system.[3]

Sevoflurane was approved for its medicinal purpose by the FDA in 1972. It’s 3X more efficient and potent than desflurane.[4] However, its potency is lower when compared to anesthetic agents like halothane and isoflurane.

Sevoflurane has a low solubility profile and blood/gas partition coefficient.[4] Moreover, the anesthetic agent has a sweet odor and doesn’t irritate the airway of patients and lab animals during administration.

In the commercial market, Sevoflurane is available in liquid form with several brand names like Ultane, Sojourn, Ultane Amerinet, and Ultane Novation.[5] In this article, you will learn how sevoflurane is applied in lab and medical procedures, its handling tips, a comparison with isoflurane, and other anesthetic agents.

How Sevoflurane Is Delivered and Its Proper Use

Sevoflurane comes in the form of a volatile liquid. It’s delivered to patients or animals using an anesthetic machine.[6] When liquid anesthetics are vaporized in the machine, it mixes the anesthetics, oxygen, and ambient air and generates the gas flow, delivering it to patients or animals.[6]

It’s highly recommended to consult a doctor or trained health professionals before using sevoflurane on patients or lab animals.[7] Any health risks of the patients or lab animals should be accounted for before administration of the anesthesia.

A host of factors that should be considered include allergies, pediatric-specific problems, geriatric-specific problems, breastfeeding, the interaction with other drugs, and other medical problems like liver, heart, kidney, or lung diseases.

Mechanism of Action

After entering the patient’s body, Sevoflurane binds with the ligand-gated ion channels and blocks central nervous system transmission, inducing an anesthesia state.[4]

The inhalation drug inhibits excitatory synaptic channel activity by binding to serotonin, nicotinic acetylcholine, and glutamate receptors. It can also enhance inhibitory postsynaptic channel activity by binding to glycine and GABA (gamma-aminobutyric acid) receptors.[4]

Furthermore, sevoflurane can also regulate the body’s activity by modulating several ion channels, affecting different ionic currents such as T-type and L-type Ca2+ currents, the Na+/Ca2+ exchange current (INCX), and the rectifier K+ currents.[4]

Safety Tips for Handling Sevoflurane

Sevoflurane possesses a certain level of hazard and causes health issues if not handled carefully while in use, such as:[8]

  • Eye irritation
  • Allergy or asthma symptoms
  • Breathing problems if inhaled
  • Organ damage in prolonged and repeated exposure
  • Infertility or causes harm to the fetus

Therefore, it’s essential to obtain special training and instructions before using sevoflurane.[8] Here’re some suggestions to follow while using sevoflurane:

  • Avoid using the chemical without reading and understanding all the safety precautions that come with the product.[8]
  • Avoid breathing mist or vapor.
  • Avoid its release into the environment.
  • Ensure that just a few people are present to limit contact with it.[8]
  • Wash thoroughly after handling the sevoflurane.
  • Wear protective gloves, clothing, and eye and face protection before using sevoflurane.
  • If exposed or concerned, immediately seek medical attention.
  • If inhaled, go into fresh air immediately and try to breathe comfortably. Also, call a doctor if there are any severe problems felt.[8]
  • If the chemical got into your eyes, rinse cautiously with clean water for several minutes.
  • If sevoflurane gets in contact with the skin, wash the skin several times with clean water. However, if the skin irritation persists, seek medical advice.[8]
  • If your clothes are contaminated with the chemical, take them off and wash them thoroughly before using them again.
  • Store sevoflurane in a well-ventilated place and keep the container tightly closed.
  • Do not dispose of the chemical’s empty containers in the open. Follow local/regional/national/international regulations.[8]

Is Sevoflurane a Better Anesthetic Agent? Sevoflurane vs. Isoflurane

Isoflurane is an ether halogenated anesthetic agent like sevoflurane. Both anesthetics have similar side effects, including dose-dependent depression of the central nervous system (CNS), vasodilation, and hypotension.

However, there are some differences between these anesthetic agents:[9]

  • Sevoflurane is less soluble than isoflurane. Thus, its induction and recovery states are achieved faster than isoflurane.[9]
  • Inducing anesthesia through the mask is faster with sevoflurane than with isoflurane.
  • The vaporizer setting of sevoflurane is higher than isoflurane because of its lesser potency. This means that a higher dose of sevoflurane is needed to keep the patients in an adequate depth of painless sleep.[9]
  • Isoflurane is pungent and can cause airway irritation when administering anesthesia in patients or animals, in chambers, and masks. While sevoflurane has a sweet odor and doesn’t irritate the airways.[9]
  • Sevoflurane allows quick change in the depth of the anesthesia compared to isoflurane. However, the patients are monitored the whole time to prevent them from going into a deep sleep or crossing the threshold of anesthesia depth.[9]
  • Sevoflurane is more expensive than isoflurane.

Though many of the above-given differences point in the direction of sevoflurane being the better anesthesia, the cost of the drug can not be ignored. Furthermore, isoflurane is still the licensed drug covering a range of animal species compared to Sevoflurane.

Thus, reducing the cost of sevoflurane and making its use more diverse (applicable to more animal species) would be a valuable addition to vet anesthesia.[10]

Are There Other Types of Anesthetic Agents?

Yes. Sevoflurane is only a single example of inhalation anesthetics. Typically, there are five classes of anesthetic agents:[11]

  1. Intravenous anesthetics: Here, anesthetics are infused into patients or animals via IV sedatives and analgesics and then maintained with volatile anesthetics. Examples are Propofol, Etomidate, Ketamine, and Dexmedetomidine.[11]
  2. Inhalational anesthetics: The anesthetic agents in these groups are inhaled. They are generally liquid at room temperature but are vaporized into a gas (during administration) for faster delivery and elimination.[11] Examples include Sevoflurane, Isoflurane, Nitrous Oxide (NO), Halothane, and Desflurane.[11]
  3. Intravenous sedatives: These anesthetic agents are often used as premedications for general anesthesia and are administered through a tube inserted into the veins. Examples are Benzodiazepines, Midazolam (Versed), Diazepam (Valium), and Lorazepam.[11]
  4. Synthetic opioids: It’s a group of drugs given to patients as an adjunct to anesthesia and to prevent severe pain. It includes drugs like sufentanil, fentanyl, alfentanil, and remifentanil.[11] There are also some semi-synthetic opioids, which include hydrocodone, hydromorphone, and oxycodone.
  5. Neuromuscular blocking drugs (NMBDs): These anesthetic agents provide laryngeal relaxation during intubation of the trachea and relaxation of skeletal muscle during surgeries. They are further grouped into competitive (non-depolarizing) and non-competitive (depolarizing) neuromuscular blocking drugs.[12] Examples are Succinylcholine, vecuronium, cisatracurium, atracurium, pancuronium, and rocuronium.[12]

Conclusion

Sevoflurane is a volatile anesthetic agent used in surgeries to induce general anesthesia in patients or lab animals. The drug is commercially available in liquid form and administered to patients using an anesthetic machine, transforming it into gas and mixing it with oxygen to make it inhalable.

Accidental contact of Sevoflurane with skin and eyes or its inhalation can cause serious harm. Thus, consult a doctor or drug expert and read the safety manual thoroughly before using the medicine in the surgeries.

Apart from sevoflurane, other anesthetic drugs commercially available include isoflurane, atracurium, and desflurane.

Are you working in a lab on procedures requiring high-quality and effective Sevoflurane anesthesia? Then, look nowhere because we’ve got you covered. Here’s the best recommended Sevoflurane to use on lab animals.

References:

  1. Sevoflurane. Retrieved from https://en.wikipedia.org/wiki/Sevoflurane
  2. General Anesthesia. Retrieved from https://www.mayoclinic.org/tests-procedures/anesthesia/about/pac-20384568#:
  3. Inhalational Anesthetic. Retrieved from https://en.wikipedia.org/wiki/Inhalational_anesthetic
  4. Sevoflurane. Retrieved from https://go.drugbank.com/drugs/DB01236
  5. Sevoflurane (Inhalation Route). Retrieved from https://www.mayoclinic.org/drugs-supplements/sevoflurane-inhalation-route/before-using/drg-20065933
  6. General Anesthetic. Retrieved from https://www.wikiwand.com/en/General_anaesthetic
  7. Sevoflurane (Inhalation Route). Retrieved from https://www.mayoclinic.org/drugs-supplements/sevoflurane-inhalation-route/description/drg-20065933
  8. Zoetis Safety Data Sheet (SDS). Retrieved from https://www2.zoetisus.com/content/_assets/docs/vmips/safety-data-sheets/sevoflo.pdf
  9. Matthews Nora (2003).Isoflurane vs. Sevoflurane. Retrieved from https://www.smiths-medical.com/-/media/M/Smiths-medical_com/Files/Import-Files/Isoflurane-vs-Sevoflurane.pdf
  10. McMillan Sam (2008). Sevoflurane or Isoflurane: Which One to Use and Why. Retrieved from https://www.vin.com/apputil/content/defaultadv1.aspx?id=3862826&pid=11254&print=1
  11. Smith G, D’Cruz JR, Rondeau B, et al. General Anesthesia for Surgeons. [Updated 2021 Oct 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2022 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK493199/
  12. Hubbell, J. A. E., & Muir, W. W. (2009). Peripheral Muscle Relaxants. Equine Anesthesia, 358–368. doi:10.1016/b978-1-4160-2326-5.00019-5