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Chloralose (alpha-chloralose) is a poisonous substance currently used as a rodenticide or avicide. It has primarily been used in Europe since 1893 as a human and veterinary hypnotic agent. Chloralose is a central nervous system depressant also acting as a stimulant on spinal reflexes. In the present case, a 24-year-old man was found dead in his bedroom near vomit residues. Several items were seized from the scene, including an empty bottle of Murex 50 g (α-chloralose), sold in Italy as rodenticide. Postmortem examination revealed no evidence of natural disease or trauma. Heart blood, urine, gastric contents, vitreous humour, brain, bile and liver were collected and submitted for toxicological analysis. Several extraction procedures and a specific liquid chromatography-tandem mass spectrometry protocol were purposely developed and validated. Chloralose was found in blood at a concentration of 65.1 mg/L and high levels were also detected in the gastric contents, confirming its ingestion shortly before the man's death. The distribution of chloralose in the body was evaluated by analyzing urine, vitreous humour, brain, bile and liver specimens. Quantitation of chloralose in several body fluids and tissues adds new data about the distribution of this chemical in the human body after massive ingestion.

Pentobarbital and alpha-chloralose are widely used for experimental anesthesia, but their direct electrophysiological actions at anesthetic concentrations are unknown. Trough and peak concentrations measured by high-performance liquid chromatography averaged 27 +/- 3 and 45 +/- 13 mg/l (means +/- SD) for pentobarbital and 41 +/- 15 and 103 +/- 13 mg/l for alpha-chloralose in dogs receiving them for general anesthesia. The direct effects of each agent on papillary muscle action potentials obtained from guinea pigs killed by decapitation were studied in vitro. Pentobarbital increased action potential duration to 95% by 24 +/- 6 and 33 +/- 4% at 25 and 50 mg/l (P less than 0.001 for each), respectively, and caused corresponding increases in effective refractory period. Furthermore, pentobarbital reduced maximum rate of voltage change (Vmax) of phase 0 in a voltage-, rate-, and concentration-dependent fashion, suggesting use-dependent sodium channel blocking actions. The voltage dependence of Vmax was shifted by 3.7 +/- 1.7 (P less than 0.01) and 6.5 +/- 1.8 mV (P less than 0.001) by 25 and 50 mg/l pentobarbital, respectively. In canine ventricular muscle, pentobarbital caused rate- and concentration-dependent decreases in Vmax and increases in action potential duration and refractory period over a concentration range of 5-100 mg/l. alpha-Chloralose was devoid of direct electrophysiological effects in both species. We conclude that pentobarbital has potentially important electrophysiological actions on ventricular tissues at concentrations required for general anesthesia and may confound the results of in vivo studies.

Bepridil is an investigational calcium antagonist that also has fast sodium channel blocking and antidysrhythmic properties. In the present study, the potential interactions of bepridil with volatile anesthetics on cardiac electrophysiologic parameters were evaluated in open-chest dogs. Twenty-four dogs anesthetized with enflurane (n=6), halothane (n=6), isoflurane (n=6), or chloralose (n=6) received 2.5 mg/kg of bepridil intravenously (IV). Twenty-five additional dogs anesthetized with enflurane (n=7), halothane (n=6), isoflurane (n=6), or chloralose (n=6), received bepridil, 5.0 mg/kg, IV. Dogs anesthetized with cloralose served as controls. Cardiac electrophysiologic parameters were measured after the dogs were anesthetized and were repeated 5, 15, 30, 45, and 60 minutes after bepridil infusion. Plasma bepridil concentrations were also determined at the above time points. Synergy between bepridil and enflurane was demonstrated in the following cardiac electrophysiologic parameters: depression of sinus node function as evidenced by severe depression of sinus node automaticity and conduction; depression of atrioventricular function as evidenced by prolongation of the atrial-His bundle interval and the Wenckebach R-R interval; and, prolongation of the atrial effective refractory period. No synergy was demonstrated between bepridil and halothane or isoflurane when compared to bepridil's effects during chloralose anesthesia. It is concluded that significant synergistic cardiac electrophysiologic effects exist between bepridil and enflurane in dogs. It is recommended that caution be used when anesthetizing patients receiving bepridil with enflurane until human data on the use of this combination of pharmacologic agents is available.

1. Alpha-chloralose, formed by the condensation of glucose with chloral, is used as a rodenticide and in the control of bird pests. 2. In two cases of poisoning with alpha-chloralose the clinical features included coma and generalized convulsions resembling the effects of strychnine more than those of chloral hydrate. 3. The principles of management are the support of vital functions in the unconscious patient and removal of unabsorbed poison by gastric lavage. Diazepam may be used to control convulsions.