Jiri Malek

Experience with a naphthylmedetomidine-ketamine-hyaluronidase combination in inducing immobilization in anthropoid apes.

Background  The aim of the study was to compare the effect of naphthylmedetomidine to medetomidine on the behavior of orangutans and chimpanzees.

Ephedrine accelerates psychomotor recovery from anesthesia in macaque monkeys

Background  Ephedrine is used in treatment of hypotension during anesthesia. We investigated its effects on the psychomotor recovery and its potential adverse reactions on cardiorespiratory functions in rhesus monkeys.

The presence of gasping predicts long-term survival in out-of-hospital cardiac arrest patients

BACKGROUND The presence of gasping in out-of-hospital cardiac arrest (OHCA) patients predicts short-term prognosis. We performed a retrospective study to evaluate whether the presence of gasping at the time of Emergency Medical Service (EMS) arrival in the case OHCA patients of presumed cardian origin has any impact on six-month survival and/or sustained return of spontaneous circulation (ROSC). METHODS We collected and analyzed Utstein Style data for all patients resuscitated for OHCA of presumed cardiac origin by the EMS of the Central Bohemian Region from July 1st, 2013 to June 30th, 2014. RESULTS During the data collection period, 565 cases of OHCA of presumed cardiac origin were reported. Gasping at the time of EMS arrival was identified in 23.9%. The presence of gasping was associated with a significantly increased frequency of sustained ROSC (48.1 versus 20.7%, P<0.001) and six-month survival (40.7 versus 16.7%, P<0.001) than in non-breathing patients. Presence of gasping upon EMS arrival has been found to be an independent positive predictor of sustained ROSC (OR 2.51, CI 95% 1.59-3.98, P<0.001). The occurrence of gasping at the time of EMS arrival at the scene was significantly related to response time from EMS activation to arrival. CONCLUSION The presence of gasping upon arrival of the EMS for the patient with OHCA of presumed cardiac origin predicts both improves short-term and long-term prognoses.

Endogenous ligands of benzodiazepine binding site have inverse agonistic properties.

Benzodiazepines have been widely used in clinical praxis for many decades. They act as GABAA receptor agonists and possess muscle-relaxant, hypnotic-sedative, anticonvulsant, and anxiolytic properties. Flumazenil acts as a benzodiazepine receptor antagonist (subunits α1, α2, α3, and α5) or partial agonist (subunits α4 and α6). It competitively inhibits the activity at the benzodiazepine recognition site on the GABA/benzodiazepine receptor complex, thereby reversing the effects of benzodiazepines. In our experiments, administration of flumazenil in rabbits was surprisingly associated with anxiolytic effects similar to those of midazolam. Additionally, flumazenil significantly and dose-dependently decreased the total number of vocalizations in rats, i.e. it was anxiolytic. These observations seem to be in contrast to the effect of flumazenil in humans, where it is believed to produce mainly anxiogenic effects. It seems that in individuals, who exhibit anxiogenic behavior or in individuals with anticipation anxiety, flumazenil acts as an anxiolytic agent, while in individuals without any signs of anxiety, flumazenil can also act as anxiogenic agent. Thus, we hypothesize that flumazenil is associated with decreased intensity of anticipatory anxiety due to occupancy of benzodiazepine binding sites by an endogenous ligand with inverse agonistic properties.