Pentobarbital dosing

The euthanasia agent used on study, Socumb, was dosed at the manufacturer s recommended dose level of 1 mlVlO lb this dose of the 6 grain/ml> solution resulted in a pentobarbital dose of 86 ng/kg, which was above the pentobarbital dose of 30 to 60 msGfg listed in the protocol. 

The potential for normal brain tissue injury is one of the limiting factors in the use of XRT for brain tumors. Pentobarbital is a cerebral radioprotectant in rodent and primate models after single doses, but is associated with significant risks. Of alternative barbiturates, thiopental given to tats receiving 70-Gy (7000-rad) whole-brain irradiation in a single fraction enhances the 30-day survival similarly to pentobarbital, whereas ethohexital and phenobarbital show no radioprotective activity (250). 

Death from overdose of barbiturates may occur and is more likely when more than 10 times the hypnotic dose is ingested. The barbiturates with high lipid solubility and short half-lives are the most toxic. Thus the lethal dose of phenobarbital is 6—10 g, whereas that of secobarbital, pentobarbital, or amo-barbital is 2-3 g. Symptoms of barbiturate poisoning include CNS depression, coma, depressed reflex activity, a positive Babinski reflex, contracted pupils (with hypoxia there may be paralytic dilation), altered respiration, hypothermia, depressed cardiac function, hypotension, shock, pulmonary complications, and renal failure. 

There are three common protocols for barbiturate detoxification. In all approaches, the goal is to prevent the occurrence of major symptoms and to minimize the development of intolerable minor symptoms. The first procedure is based on protocols described by several authors (Ewing and BakeweU 1967 Isbell 1950 Wilder 1968) (see Table 3 ). The first step is to determine the severity of tolerance. If the patient is intoxicated, no additional barbiturate should be given until the symptoms of intoxication have resolved. If there is substantial evidence or strong suspicion of chronic barbiturate use, it is not necessary or desirable to wait until withdrawal symptoms appear. A 200-mg oral dose of pentobarbital may be given on an empty stomach to a... 

Winters WD, Kott KS Continuum of sedation, activation and hypnosis or hallucinosis a comparison of low dose effects of pentobarbital, diazepam or gamma-hydroxy-butyrate in the cat. Neuropharmacology 18 877—884, 1979... 

Pentobarbital is commonly loaded at a dose of 10 to 15 mg/kg over 1 to 2 hours, followed by a continuous infusion of 0.5 to 4 mg/kg per hour. Therapy can be tapered off after 12 to 24 hours of seizure control as evident on the EEG.35 One metaanalysis reported a lower incidence of treatment failure with pentobarbital (3%) when compared to midazolam (21%) or propofol (20%), although the risk of hypotension requiring vasopressor therapy was higher when pentobarbital was used.36 This relative efficacy for pentobarbital must be considered... 

At least 1 week after their arrival, the rats are given atropine sulfate (0.4 mg/kg, i.p.) and anesthetized with sodium pentobarbital (50 mg/kg i.p.) or isoflurane gas (5%). When necessary, supplemental doses of sodium pentobarbital are given or isoflurane gas is adjusted to maintain anesthesia. The rats are hydrated with 0.9% saline (3.0 cc, s.c.) and given penicillin (0.05 cc 1500 units, i.m.). 

Respiratory and cardiovascular effects of maitotoxin have been studied in pentobarbital anaesthetized cats (21). Sublethal doses of maitotoxin induced an important hyperventilation phase, hypertension and a transitory tachycardia followed by slight bradycardia. Higher dosage caused respiratory depression, cardiac arrhythmias and tachycardia leading to cardiac failure. Artificial respiration did not modify the cardiac responses. 

Pentobarbital (Nembutal, Others) [C-ll] [Anticonvulsant, Sedative/ Hypnotic/Barbiturate] Uses Insomnia, convulsions, induce coma following severe head injury Action Barbiturate Dose Adults. Sedative ... 

In cats anesthetized with sodium pentobarbital, an intravenous dose of III at 25 mg/kg was found to be able to block almost comletely the cardiac response to stimulation of the peripheral right vagus nerve.121 Small doses (2-8 mg/kg) did not inhibit peristaltic activity in... 

Kirk T, Roache JD, Griffiths RR. Dose-response evaluation of the amnestic effects of triazolam and pentobarbital in normal subjects. J Clin Psychopharmacol 1990 10 161-168. 

The root bark of the cultivated mulberry tree was extracted successively with n-hexane, benzene, and methanol. The methanol extract, 1—20 mg, showed a dose-dependent decrease in arterial blood pressure in pentobarbital-anesthetized rabbit, Fig. (4). The extract was fractionated successively by silica gel column chromatography (C.C.), polyamide C.C., silica gel preparative (p.) TLC, and p. HPLC leading to isolated of kuwanons G (1,0.2% yield) [9] and H (2,0.13% yield) [10]. 

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