Studies on concentration-time profiles of nimodipine enantiomers following intravenous and oral administration of nimodipine in patients with subarachnoid hemorrhage.

After i.v. and oral administration of nimodipine the concentration-time profiles of the drug and its enantiomers were studied in seven patients with subarachnoid hemorrhage. Concentrations of nimodipine, (+)-(R)-, and (-)-(S)-nimodipine were analyzed using a new stereoselective high-performance liquid chromatographic method. During the first 3 h after oral administration the concentrations of (+)-(R)- and (-)-(S)-nimodipine were significantly different, the (-)-(S)-enantiomer being found in much lesser concentrations compared to the (+)-(R)-enantiomer. The results indicate that if uptake from the gastrointestinal system is equal for the two enantiomers, then (-)-(S)-nimodipine is metabolized at a much faster rate compared to (+)-(R)-nimodipine after oral administration of the drug in patients with subarachnoid bleeding. After i.v. administration; no significant differences between the concentrations of the (-)-(S) and the (+)-(R) isomers were demonstrated.

[Lightning injuries. Mechanisms and treatment]. / Lynulykker. Skademekanismer og behandling.

Lightning injuries occur sporadically and are rarely seen in emergency departments, during the years 1991-1993 there have been 12 admissions due to this cause in Denmark. The special mechanisms of damage in lightning accidents are illustrated by review of the literature. The clinical findings are described, especially the transient neurological damage characterises lightning accidents. Contrary to what one would expect, the victim often survives a lightning accident. This is surprising considering the tremendous powers of nature involved and the serious clinical manifestations. Prevention is important, this is the reason why the population should be taught the appropriate behaviour if there is a thunderstorm. Resuscitation should be started immediately and continued even though the victim seems lifeless and might have dilated pupils not reacting to light. Good results have been reported even after prolonged resuscitation.

[Lightning accidents in ]rhus 1991-1993]. / Lynulykker i Arhus 1991-1993.

During the years 1991-1993, the emergency department of Arhus Kommune Hospital received four victims of lightning accidents. Two of these were admitted to the intensive care unit for further treatment and observation. This case report brings their histories including clinical findings. Possible mechanisms of damage are discussed and the importance of immediate and continued resuscitation of the presumably lifeless victim of a lightning accident is confirmed. All four patients recovered without serious physical sequelae.

Continuous end-tidal carbon dioxide monitoring during normofrequent jet-ventilation.

BACKGROUND: Continuous end-tidal carbon dioxide (ETCO2) monitoring during normofrequent jet-ventilation (NFJV) has not previously been successful and no correspondence between ETCO2 and arterial carbon dioxide (PaCO2) demonstrated. METHODS: During NFJV jet-ventilation in 19 healthy volunteers, continuous ETCO2 was measured and compared to PaCO2 values. The original ETCO2 sampling line from our Datex CO2 measuring equipment was placed longitudinally against a suction catheter and both were wrapped with aluminium foil. They were placed 4-5 cm above the carina and the position was verified with a fiberoptic bronchoscope. RESULTS: The correlation between methods gave a Pearson's product moment correlation (r value) of 0.836, significant at the P < 0.001 level, indicating a close correlation between methods. A difference against mean scatter diagram confirmed that ETCO2 and PaCO2 measurements are of equal value in monitoring healthy patients during NFJV. CONCLUSION: A valuable method of continuous ETCO2 monitoring during NFJV is presented.

Axotomized, adult basal forebrain neurons can innervate fetal frontal cortex grafts: a double fluorescent tracer study in the rat.

The ability of axonal regeneration of identified adult basal forebrain (BFB) neurons was examined after homotopic grafting of fetal neocortical tissue to a lesion cavity in the frontal neocortex. Using a four step experimental procedure, adult rats first received an injection of the fluorescent dye Fluoro-Gold (FG) into the sensorimotor cortex in order to label those neurons with projections to the area by retrograde axonal transport. After one week the injection area was removed by aspiration, leaving a cavity in the neocortex. One week later a block of fetal (E14) frontal cortical tissue was placed in the cavity. The animals were then allowed to survive for 6 weeks before a second fluorescent tracer, Nuclear Yellow (NY), was injected into the transplant. The animals were sacrificed 24 h later and analyzed by fluorescence microscopy. Both single labeled, FG and NY containing neurons and double labeled neurons containing both tracers were found in the BFB. The results demonstrate that adult BFB neurons can reestablish cortical projections into fetal cortical grafts (double labeled neurons), and they suggest that other BFB neurons, not initially innervating the lesioned cortical area, have sprouted into the transplant (NY labeled neurons).