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Chloral Hydrate (chloral + hydrate)
Selected AbstractsPentobarbital vs chloral hydrate for sedation of children undergoing MRI: efficacy and recovery characteristicsPEDIATRIC ANESTHESIA, Issue 7 2004Shobha Malviya MD Summary Background :,Chloral hydrate (CH) sedation for magnetic resonance imaging (MRI) is associated with significant failure rates, adverse events and delayed recovery. Pentobarbital (PB), reportedly produces successful sedation in 98% of children undergoing diagnostic imaging. This study compared the efficacy, adverse events and recovery characteristics of CH vs PB in children undergoing MRI. Methods :,With Institutional Review Board approval and written consent, children were randomly assigned to receive intravenous (i.v.) PB (maximum 5 mg·kg,1 in incremental doses) or oral CH (75 mg·kg,1) prior to MRI. Sedation was augmented with 0.05 mg·kg,1 doses of i.v. midazolam (maximum 0.1 mg·kg,1) as necessary. Adverse effects, including hypoxaemia, failed sedation, paradoxical reactions and behavioural changes, the return of baseline activity, and parental satisfaction were documented. The quality of MRI scans was evaluated by a radiologist blinded to the sedation technique. Results :,PB facilitated an earlier onset of sedation (P = 0.001), higher sedation scores (P = 0.01), and less need for supplemental midazolam compared with CH. Severe hypoxaemia occurred in two children (6%) in the PB group. Fourteen per cent of the PB group experienced a paradoxical reaction, 9% sedation failure and 11% major motion artefact, compared with 0% (P = 0.05), 3 and 2% (P = NS), respectively, in the CH group. CH and PB were both associated with a high incidence of motor imbalance, and agitation. However, children who received PB had a slower return to baseline activity (P = 0.04). Conclusions :,Although PB facilitated a quicker sedation onset and reduced the requirement for supplemental sedation, it produced a higher incidence of paradoxical reaction and prolonged recovery with a similar failure rate compared with CH. [source] Effects of cannabinoids on prefrontal neuronal responses to ventral tegmental area stimulationEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2001Marco Pistis Abstract Cannabinoids activate the firing of mesoprefrontocortical dopamine neurons and release dopamine in the prefrontal cortex. This study was undertaken with the aim of clarifying the interaction between cannabinoids and mesocortical system in the prefrontal cortex. The effect of ,9 -tetrahydrocannabinol (,9 -THC) and the synthetic CB1 agonist WIN55,212,2 (WIN) was studied by extracellular single unit recordings, in chloral hydrate anaesthetised rats, on the spontaneous activity of pyramidal neurons and on the inhibition produced on these neurons by the electrical stimulation of the ventral tegmental area (VTA). Intravenously administered ,9 -THC and WIN (1.0 and 0.5 mg/kg, respectively), increased the firing rate of pyramidal neurons projecting to the VTA. VTA stimulation produced a phasic inhibition (167 ± 6 ms) in 79% of prefrontal cortex pyramidal neurons. ,9 -THC and WIN reverted this inhibition in 73% and 100% of the neurons tested, respectively. The subsequent administration of the selective CB1 antagonist SR141716A (1 mg/kg) readily suppressed the effects of both cannabinoids and restored the inhibitory response to VTA stimulation. Moreover, when administered alone, SR141716A prolonged the inhibition in 55.6% of the neurons tested. The results indicate that stimulation of CB1 receptors by cannabinoids results in an enhanced excitability of prefrontal cortex pyramidal neurons as indexed by the suppression of the inhibitory effect of VTA stimulation and by the increase in firing rate of antidromically identified neurons projecting to the VTA. Furthermore, our results support the view that endogenous cannabinoids exert a negative control on dopamine activity in the prefrontal cortex. This study may be relevant in helping to understand the influence of cannabinoids on cognitive processes mediated by the prefrontal cortex. [source] Subchronic toxicity of chloral hydrate on rats: a drinking water studyJOURNAL OF APPLIED TOXICOLOGY, Issue 4 2002R. Poon Abstract The subchronic toxicity of chloral hydrate, a disinfection byproduct, was studied in rats following 13 weeks of drinking water exposure. Male (262 ± 10 g) and female (190 ± 8 g) Sprague-Dawley rats, ten animals per group, were administered chloral hydrate via drinking water at 0.2, 2, 20 and 200 ppm. Control animals received distilled water only. Gross and microscopic examinations, serum chemistry, hematology, biochemical analysis, neurogenic amine analysis and serum trichloroacetic acid (TCA) analysis were performed at the end of the treatment period. Bronchoalveolar fluids were collected at necropsy and urine specimens were collected at weeks 2, 6 and 12 for biochemical analysis. No treatment-related changes in food and water intakes or body weight gains were observed. There were no significant changes in the weights of major organs. Except for a mild degree of vacuolation within the myelin sheath of the optic nerves in the highest dose males, there were no notable histological changes in the tissues examined. Statistically significant treatment-related effects were biochemical in nature, with the most pronounced being increased liver catalase activity in male rats starting at 2 ppm. Liver aldehyde dehydrogenase (ALDH) was significantly depressed, whereas liver aniline hydroxylase activity was significantly elevated in both males and females receiving the highest dose. A dose-related increase in serum TCA was detected in both males and females starting at 2 ppm. An in vitro study of liver ALDH confirmed that chloral hydrate was a potent inhibitor, with an IC50 of 8 µM, whereas TCA was weakly inhibitory and trichloroethanol was without effect. Analysis of brain biogenic amines was conducted on a limited number (n = 5) of male rats in the control and high dose groups, and no significant treatment-related changes were detected. Taking into account the effect on the myelin sheath of male rats and the effects on liver ALDH and aniline hydroxylase of both males and females at the highest dose level, the no-observed-effect level (NOEL) was determined to be 20 ppm or 1.89 mg kg,1 day,1 in males and 2.53 mg kg,1 day,1 in females. This NOEL is ca. 1000-fold higher than the highest concentration of chloral hydrate reported in the municipal water supply. Copyright © 2002 Crown in the right of Canada. Published by John Wiley & Sons, Ltd. [source] Pentobarbital vs chloral hydrate for sedation of children undergoing MRI: efficacy and recovery characteristicsPEDIATRIC ANESTHESIA, Issue 7 2004Shobha Malviya MD Summary Background :,Chloral hydrate (CH) sedation for magnetic resonance imaging (MRI) is associated with significant failure rates, adverse events and delayed recovery. Pentobarbital (PB), reportedly produces successful sedation in 98% of children undergoing diagnostic imaging. This study compared the efficacy, adverse events and recovery characteristics of CH vs PB in children undergoing MRI. Methods :,With Institutional Review Board approval and written consent, children were randomly assigned to receive intravenous (i.v.) PB (maximum 5 mg·kg,1 in incremental doses) or oral CH (75 mg·kg,1) prior to MRI. Sedation was augmented with 0.05 mg·kg,1 doses of i.v. midazolam (maximum 0.1 mg·kg,1) as necessary. Adverse effects, including hypoxaemia, failed sedation, paradoxical reactions and behavioural changes, the return of baseline activity, and parental satisfaction were documented. The quality of MRI scans was evaluated by a radiologist blinded to the sedation technique. Results :,PB facilitated an earlier onset of sedation (P = 0.001), higher sedation scores (P = 0.01), and less need for supplemental midazolam compared with CH. Severe hypoxaemia occurred in two children (6%) in the PB group. Fourteen per cent of the PB group experienced a paradoxical reaction, 9% sedation failure and 11% major motion artefact, compared with 0% (P = 0.05), 3 and 2% (P = NS), respectively, in the CH group. CH and PB were both associated with a high incidence of motor imbalance, and agitation. However, children who received PB had a slower return to baseline activity (P = 0.04). Conclusions :,Although PB facilitated a quicker sedation onset and reduced the requirement for supplemental sedation, it produced a higher incidence of paradoxical reaction and prolonged recovery with a similar failure rate compared with CH. [source] Anaesthesia for magnetoencephalography in children with intractable seizuresPEDIATRIC ANESTHESIA, Issue 9 2003Peter Szmuk MD Summary Background Magnetoencephalography (MEG), a noninvasive technique for evaluation of epileptic patients, records magnetic fields during neuronal electrical activity within the brain. Anaesthesia experience for MEG has not yet been reported. Methods We retrospectively reviewed records of 48 paediatric patients undergoing MEG under anaesthesia. Thirty-one patients (nonprotocol group) were managed according to the anaesthesiologist's discretion. Premedication included oral midazolam, chloral hydrate or fentanyl oralet, intravenous midazolam or inhalational anaesthesia with sevoflurane. Anaesthesia was maintained with propofol, midazolam, fentanyl, alone or in combination. A subsequent protocol group (17 patients) received chloral hydrate as premedication and propofol for maintenance of anaesthesia. Results There was an overall 25% failure of interictal activity and localization on the MEG scan. In the nonprotocol group, 11 scans failed (35.5%). Of these, eight (72.7%) received midazolam orally. Only one failure (5.8%) was recorded in the protocol group in a patient who received chloral hydrate as sedation supplemented by sevoflurane. Conclusions In our experience, midazolam premedication resulted in a high MEG failure rate (73%). Chloral hydrate premedication and propofol maintenance resulted in a lower incidence of MEG failure (5.8%). General anaesthesia with a continuous infusion of propofol or sevoflurane appears acceptable, although, lighter levels of anaesthesia might be required to avoid interference with interictal activity of the brain. [source] Haemodynamic changes after spinal cord transection are anaesthetic agent dependentAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 4 2007P. R. Leal Summary 1 To evaluate the effect of high spinal cord transection (SCT), between T4 and T5, on the mean arterial pressure (MAP) and heart rate in animals anaesthetized with different anaesthetic agents: ether (n = 12), 20% urethane, 1.2 g kg,1 (n = 12), 2% tri-bromide-ethanol, 200 mg kg,1 (n = 12); chloral hydrate and urethane, 75 and 525 mg kg,1 respectively (n = 12). 2 In the animals anaesthetized with ether or urethane, SCT caused an immediate major drop in MAP, with hypotension and bradycardia throughout the next 10 min. In the animals anaesthetized with urethane + chloralose or tri-bromide-ethanol, SCT transiently increased MAP with subsequent hypotension and bradycardia. 3 In summary, the haemodynamic changes after complete, high SCT are anaesthetic agent dependent. Further research about the exact mechanisms responsible for these diverse autonomic changes is warranted. [source] Treatment of neonatal abstinence syndrome with clonidine and chloral hydrateACTA PAEDIATRICA, Issue 2 2010A Esmaeili Abstract Aim:, The objective of this retrospective study is to compare the medical treatment of neonatal narcotic abstinence syndrome with clonidine and chloral hydrate with the commonly used combination therapy of morphine and phenobarbital. Methods:, From 1998 to 2008, a total of 133 newborns suffering from neonatal narcotic abstinence syndrome were treated at our clinic. All of these patients were born to mothers who had received methadone substitution for drug addiction during the course of pregnancy. Results:, Twenty-nine patients received clonidine and chloral hydrate, and 64 patients were treated with morphine and phenobarbital for abstinence syndrome. The duration of treatment was significantly shorter in the clonidine/chloral hydrate group (median: 14 days vs. 35 days). Correspondingly, the period of hospitalization was also considerably shorter in the clonidine/chloral hydrate group (median: 32 days vs. 44 days). In addition, patients in the clonidine/chloral hydrate group exhibited markedly reduced withdrawal symptoms. Conclusion:, This study suggests that a treatment of neonatal abstinence syndrome with clonidine in omission of opiates is possible without causing short-term adverse cardiovascular effects. Considering the retrospective design of the study, controlled and prospective trials are needed. [source] | ||||||||||