Anesthetic Agents and Surgery during Pregnancy
“Bert” Bertis Britt Little in Drugs and Pregnancy, 2022
Halothane is the prototype halogenated anesthetic agent. It was not associated with an increased frequency of birth defects among 26 infants whose mothers received halothane in the first trimester (Heinonen et al., 1977). Increased fetal loss, growth retardation, malformations, and behavioral abnormalities were reported in animal studies of halothane in pregnancy (Friedman, 1988). A case-control study of birth defects in infants born to female nurses exposed to anesthetic drugs during the first trimester found an increased frequency of birth defects associated with halothane, isoflurane, sevoflurane, and nitrous oxide compared to 1,026 infants born to women not exposed to anesthetic gases during pregnancy (Table 6.3). It is important to note that the sample sizes are small, and the data are based entirely on self-report. Women with an infant with a birth defect are more likely to report exposures than women who had an infant without a birth defect (Teschke et al., 2011).
Euthanasia and Necropsy
Yuehuei H. An, Richard J. Friedman in Animal Models in Orthopaedic Research, 2020
Inhalant anesthetics include halothane, methoxyflurane, enflurane, isoflurane and ether. Ether is explosive, flammable and very irritating and for these reasons it is not recommended.17 Gas overdose is an excellent choice for small (<7 kg) animals where venipuncture is technically difficult and in chickens.1 Halothane, methoxyflurane and isoflurane are nonflammable, nonexplosive and can be delivered either in a closed container like a closed chamber or bell jar or via a face mask. Care must be taken to ensure that there is an adequate supply of air inside the closed chamber and that the animal does not come in direct contact with the liquids as they are irritating. Halothane is the most soluble and most effective for inducing rapid loss of consciousness and, therefore, is the agent of choice.1 Isoflurane is the least soluble but it has a pungent odor and animals tend to hold their breath. Death is the result of direct suppression of respiration and of the cerebral cortex, and other vital centers.1 These agents have been reported to cause no alterations in the histology of most tissues except for congestion of alveolar capillaries.13 Both halothane and methoxyflurane have been shown to alter some metabolic parameters7,14 and cause lymphocyte proliferation.15
Anesthetics
Bev-Lorraine True, Robert H. Dreisbach in Dreisbach’s HANDBOOK of POISONING, 2001
Approximately 500 fatalities that are at least partly due to the administration of anesthetic agents occur each year in the USA. The overall fatality rate following administration of anesthetic agents is approximately 0.5–1 per 10 000. The incidence of hepatic necrosis following halothane administration is 1 per 10 000 after a single administration, which is not significantly different from that found with other anesthetic agents. The incidence of hepatic necrosis after halothane administration rises to 7 per 10000 after multiple exposures. Hepatic necrosis after halothane administration is assumed to be an autoimmune response.
Management of adreno-cortical adenomas using microwave ablation: study of the effects of the fat tissue
Published in International Journal of Hyperthermia, 2022
Anna Bottiglieri, Martin O’Halloran, Giuseppe Ruvio, Laura Farina
An acute animal study is conducted at the Hospital Virtual Valdecilla (HvV), Santander, Cantabria, Spain, according to the approved protocol (National Regulatory Body approval and HvV Ethical Committee authorisation). An adult 20 kg sheep is used to test the ablation hypothesis in vivo on the left adrenal gland. The animal is positioned on dorsal recumbency and anesthetised with Ketamine (15–35 mg/kg) and xylazine (5 mg/kg). The anesthesia is maintained by halothane or isofluorane for the duration of the procedure. To access the adrenal gland, a ventral midline celiotomy is executed and the triaxial MW applicator is placed in direct contact with the surface of the adrenal gland beneath the adrenal layer. The use of a triaxial antenna makes access to the adrenal gland easier and less invasive due to the smaller diameter compared with the monopole antenna used in the ex vivo study. Figure 3 shows the positioning of the MW applicator adjacent to the adrenal gland and the surrounding fat; the figure also shows a schematization of the experimental setup.
Halogen gas exposure: toxic effects on the parturient
Published in Toxicology Mechanisms and Methods, 2021
Dylan R. Addis, James A. Lambert, David A. Ford, Tamas Jilling, Sadis Matalon
The elemental halogens are oxidizing and electrophile agents comprising Group 17 of the periodic table with a multitude of commercial and industrial uses. While these elements are utilized broadly in a variety of contexts in the modern era, the history of inhaled anesthetics provides an informative context through which to understand the potential benefits, toxic potential, and weaponization of halogen derivatives. The halogenated inhalational anesthetics are a prime example of the medicinal utility of the halogens with halothane being halogenated with fluorine, chlorine, and bromine; isoflurane with fluorine and chlorine; and both sevoflurane and desflurane halogenated only with fluorine (Suckling and Raventos 1958; Sherer and Kuhn 1960; Suckling and Raventos 1960; Rozov et al. 1993; Rozov et al. 1995; Terrell 1999).
Perioperative pharmacotherapy to prevent cardiac complications in patients undergoing noncardiac surgery
Published in Expert Opinion on Pharmacotherapy, 2021
Kirtipal Bhatia, Bharat Narasimhan, Gaurav Aggarwal, Adrija Hajra, Soumya Itagi, Shathish Kumar, Sandipan Chakraborty, Neelkumar Patel, Vardhmaan Jain, Dhrubajyoti Bandyopadhyay, Birendra Amgai, Wilbert S Aronow
Among the volatile anesthetics, halothane has been shown to reduce myocardial perfusion in a dose-dependent fashion [105]. Etomidate, an intravenous anesthetic, has been found to be associated with longer length of hospital stay, increased risk of mortality, and cardiovascular morbidity [106]. A more recent multicenter randomized controlled trial, however, failed to show any difference in cardiovascular morbidity and mortality between patients receiving sevoflurane or propofol for maintenance of anesthesia [107]. According to the American College of Cardiology/AmericanHeart Association (ACC/AHA) guidelines (2014), volatile agents or intravenous anesthetics are reasonable for anesthesia maintenance in patients at risk for myocardial ischemia [42]. Regional anesthesia has a theoretical advantage for preventing postoperative cardiac complications and can be utilized as an alternative for selected patients with high cardiac risk.
Related Knowledge Centers
- Anesthesia
- Arrhythmia
- Hepatotoxicity
- Malignant Hyperthermia
- Tracheal Intubation
- Inhalation
- Hypoventilation
- Saliva
- Porphyria
- General Anaesthetic