Pentobarbital for

Holmes GL, Riviello JJ. Midazolam and pentobarbital for refractory status epilepticus. Pediatr Neurol 1999 20 259-264. 

A. Pentobarbital is used for the management of status epilepticus that is unresponsive to conventional anticonvulsant therapy (eg, diazepam, phenytoin, or phenobarbital). If the use of pentobarbital for seizure control is considered, consultation with a neurologist is recommended. 

Mallory MD, Baxter AL, Kost SI. Propofol vs. pentobarbital for sedation of children undergoing magnetic resonance imaging results from the Pediatric Sedation Research Consortium. Paediatr Anaesth 2009 19(6) 601-11. 

Zgleszewski SE, Zurakowski D, Fontaine PJ, D Angelo M, Mason KP. Is propofol a safe alternative to pentobarbital for sedation during pediatric diagnostic CT Radiology 2008 247(2) 528-34. 

Metabolism Probable propylene glycol toxicity has been reported in a patient receiving a continuous infusion of pentobarbital for refractory status epilepticus [63 ]. 

Barbituric acids as their name implies are weakly acidic and are converted to then-sodium salts (sodium barbiturates) m aqueous sodium hydroxide Sometimes the drug is dispensed m its neutral form sometimes the sodium salt is used The salt is designated by appending the word sodium to the name of the barbituric acid—pentobarbital sodium for example... 

Although most anesthetics are achiral or are adininistered as racemic mixture, the anesthetic actions are stereoselective. This property can define a specific, rather than a nonspecific, site of action. Stereoselectivity is observed for such barbiturates as thiopental, pentobarbital, and secobarbital. The (3)-enantiomer is modestly more potent (56,57). Additionally, the volatile anesthetic isoflurane also shows stereoselectivity. The (3)-enantiomer is the more active (58). Further evidence that proteins might serve as appropriate targets for general anesthetics come from observations that anesthetics inhibit the activity of the enzyme luciferase. The potencies parallel the anesthetic activities closely (59,60). 

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). 

Pentobarbital, marketed under the name Nembutal, is a barbiturate used i treating insomnia. It is synthesized in three steps from diethyl maionatt Show how you would synthesize the dialkylated intermediate, and then pre pose a mechanism for the reaction of that intermediate with urea to giv pentobarbital. 

The other method used is infusion of intravenous anaesthetics such as propofol, etomidate (for induction) and the barbiturates such as thiopental and pentobarbital. Investigations into the mechanism of anaesthesia have made use of all these compounds in order to identify a common mode of action linked to likely mechanisms within the CNS. 

The ultra-short-acting barbiturates include methohexital sodium (Brevi-tal) and thiopental sodium (Pentothal). These agents are used as anesthetics and are administered intravenously. Barbiturates with short-to-intermediate duration of action are used for their sedative-hypnotic effect in the treatment of anxiety. These medications include amobarbital (Amytal), butabarbital (Butisol), sodium pentobarbital (Nembutal), and secobarbital (Seconal). 

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... 

Buck K, Metten P, Belknap J, et al Quantitative trait loci affecting risk for pentobarbital withdrawal map near alcohol withdrawal loci on mouse chromosomes 1, 4, and... 

Other sedative-hypnotic medications, such as barbiturates, may play a useful role in severe withdrawal from this group of drugs. For example, in a case series of GBL withdrawal, use of intravenous pentobarbital in the range of 1-2 mg/kg/hour lowered the total requirement for intravenous lorazepam (Sivilotti et al. 2001). Antipsychotic medications are often used to reduce psychotic agitation. However, because antipsychotic medications lower the seizure threshold and may contribute to loss of central control of temperature leading to hyperthermia or neuroleptic malignant syndrome (NMS), they are not indicated as first-line medications for GHB withdrawal delirium (Dyer and Roth 2001 McDaniel and Miotto 2001 Sharma et al. 2001). If anti-... 

Research in rodents has provided evidence of solvent withdrawal. Continuous exposure to toluene for 4 days and subsequent cessation produced an increase in handling-induced convulsions for at least 2 hours after cessation (Wiley et al. 2003). A similar pattern of trichloroethane administration to rodents produced pronounced withdrawal, which was worsened by the administration of the proconvulsant drug pentylenetetrazole and attenuated by reexposure to 2,000 ppm of toluene or the administration of alcohol, pentobarbital, or midazolam (Evans and Balster 1993). 

Male, Sprague-Dawley rats were implanted under pentobarbital anesthesia with a bipolar electrode in the right dorsal hippocampus for hippocampal stimulation and recording. Stainless steel screws were also placed over the contralateral frontal and parietal cortices for recording cortical seizure activity. The electrodes... 

Midazolam, propofol, and pentobarbital infusions can be used for refractory status epilepticus but may require intensive monitoring and supportive care. 

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... 

A discussion of all the reasons for this phenomenon is beyond the scope of this chapter, but a simple example will illustrate the concept. Highly lipid-soluble drugs, such as pentobarbital, are preferentially distributed into adipose tissue. The result is that plasma concentrations are extremely low after distribution is complete. When the apparent volumes of distribution are calculated, they are frequently found to exceed total body volume, occasionally by a factor of 2 or more. This would be impossible if the concentration in the entire body compartment were equal to the plasma concentration. Thus, Vd is an empirically fabricated number relating the... 

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