Propofol Halothane

Reduction of secretions and vagal reflexes Muscarinic antagonists, usually hyoscine, are used to prevent salivation and bronchial secretions and, more importantly, to proteci the heart from arrhythmias, particularly bradycardia caused by halothane, propofol, suxamethonium and neostigmine. Hyoscine is also iiniiemeiic and produces some amnesia. 

The following agents may be affected by theophylline Benzodiazepines, -agonists, halothane, ketamine, lithium, nondepolarizing muscle relaxants, propofol, ranitidine, and tetracyclines. Probenecid may increase the effects of dyphylline. 

Kitamura A, Sato R, Marszalec W, et al. Halothane and propofol modulation of gamma-aminobutyric acid A receptor single-channel currents. Anesth Analg. 2004 99 409-415. 

Bhattacharya AA, Curry S, Franks NP (2000) Binding of the general anesthetics propofol and halothane to human... 

A randomized prospective trial in 60 children undergoing outpatient anesthesia showed a 30% shorter time from discontinuation of anesthesia to eye opening and return to full wakefulness in patients receiving propofol alone compared with halothane + nitrous oxide anesthesia (14). Propofol was associated with a 17% incidence of emesis compared with 58 and 53% for halothane + nitrous oxide and propofol + nitrous oxide anesthesia respectively. 

Crawford MW, Lerman J, Sloan MH, Sikich N, Halpern L, Bissonnette B. Recovery characteristics of propofol anaesthesia, with and without nitrous oxide a comparison with halothane/nitrous oxide anaesthesia in children. Paediatr Anaesth 1998 8(l) 49-54. 

An obese 35-year-old diabetic woman developed isoflurane-induced hepatotoxicity (15). She had had four previous halothane anesthetics, the last two of which were associated with jaundice. She made a full recovery and during a subsequent anesthetic received an infusion of propofol. Unfortunately, trifluoroacetic acid antibody titers were not performed. Liver function does not appear to have been severely affected peak alanine transaminase activity was 1410 IU/1. 

Plasma activity of alpha-glutathione 5-transferase activity (aGT) is a more sensitive and specific marker of hepatocellular injury than transaminase activity and it correlates better with hepatic histology. Anesthesia with halothane leads to transiently raised aGT activity, but propofol and isoflurane do not. In a randomized study of plasma aGT activity during and after low-flow anesthesia with sevoflurane or isoflurane, there were no significant differences in aGT activities between the two groups during or after anesthesia (34). 

Bufalari A, Miller S M, Giannoni C et al 1998 The use of propofol as an induction agent for halothane and isoflurane anesthesia in dogs. Journal of the American Animal Hospital Association 34 84-91... 

Prototypical Compounds Inhalational agents Halothane Isoflurane Enflurane, Sevoflurane. Intravenous agents Propofol... 

Chemical Formula Inhalational - Halothane C2HBrClF3 Isoflurane C3H2CIF5O Enflurane C3H2OCIF5 Sevoflurane C4H3F7O. Intravenous -Propofol C12 HjgO... 

Aono J, Mamiya K, Manabe M Preoperative anxiety is associated with a high incidence of problematic behavior on emergence after halothane anesthesia in boys. Acta Anaesthesiol Scand 43 542-544,1999 Gozal D, Gozal Y Behavior disturbances with repeated propofol sedation in a child (letter). J Clin Anesth 11 499,1999... 

Fentanyl, ketamine, midazolam, propofol, thiopental Enflurane, desflurane, halothane, isoflurane, nitrous oxide, sevoflurane... 

Antimuscarinic drugs are used as premedication to prevent salivation and bronchial secretions during an operation and to protect the heart from arrhythmias caused by inhalation anaesthetics such as halothane and propofol. They are less commonly used nowadays because modern anaesthetics are less irritant. 

B. Propofol levels may be increased by lidocaine, bupivacaine, and halothane, producing an increased hypnotic effect. 

In general, the effects of the combined use of general anaesthetics are at least additive. The required dose of propofol will be lower if it is given with nitrous oxide, halothane or isoflurane. The anaesthetic effects of propofol and sevoflurane appear to be additive in ECT, and synergy has been reported between propofol and eto-midate. 

In a study in 20 healthy patients the concurrent use of either halothane or isoflurane increased the serum concentrations of propofol by about 20% during the maintenance of general anaesthesia. The US manufacturer of propofol notes that inhalational anaesthetics (such as halothane or isoflurane) would be expected to increase the effects of propofol. The man-... 

Propofol, barbiturates and halothane appear to interact with benzodiazepines through their effects on the gamma-aminobutyric acid (GABA) receptor. 

The interactions between propofol or thiopental and midazolam are well established. This synergy has been utilised for the induction of anaesthesia. Midazolam also reduces the dose requirements of halothane. Other benzodiazepines may also potentiate the effects of general anaesthetics. 

Patients anaesthetised with inhalational anaesthetics (particularly cyclopropane and halothane, and to a lesser extent desflurane, enflurane, ether, isoflurane, methoxyflurane, and sevoflurane) can develop cardiac arrhythmias if they are given adrenaline (epinephrine) or noradrenaline (norepinephrine), unless the dosages are very low. Children appear to be less susceptible to this interaction. file addition of adrenaline to intrathecal tetracaine enhances the sedative effects of propofol. 

A 71-year-old man undergoing a minor orthopaedic operation was given a 500-microgram intravenous injection of alfentanil followed by a slow injection of propofol 2.5 mg/kg. Approximately 15 seconds after the propofol, the patient developed strong bilateral fits and grimaces, which lasted for 10 seconds. Anaesthesia was maintained with nitrous oxide/oxygen and halothane and there were no other intra- or postoperative complications. The patient had no history of convulsions. Propofol has also been associated with opisthotonos (a spasm where the head and heels bend backwards and the body arches forwards) in two patients given fentanyl... 

Tricyclic antidepressants may increase the risk of arrhythmias and hypotension during anaesthesia. Tachyarrhythmias have been seen in patients taking imipramine who were given halothane and pancuronium. Some very limited evidence su ests that amitriptyline may increase the likelihood of enflurane-induced seizure activity. A man taking maprotiline and lithium developed a tonic-clonic seizure when given propofol. Tricyclics may cause an increase in the duration of barbiturate anaesthesia and lower doses of barbiturates may be required. 

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