Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0020440 (hypercapnia)
 7,939 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Dexmedetomedine is a potent alpha 2 adrenergic agonist which can reduce anesthetic requirements by over 90% in rats and dogs. This study examined the effects of various doses of dexmedetomidine on the following monitored variables in New Zealand white rabbits: arterial blood gases, mean arterial pressure, respiratory rate, heart rate, and level of sedation. Following the percutaneous insertion of arterial and venous catheters, 21 rabbits received an infusion of saline or dexmedetomidine (20, 80 or 320 micrograms/kg). Monitored variables were recorded at 5, 15, 30 and 60 min following the infusion. Dexmedetomidine produced significant dose-dependent increases in PaCO2 and level of sedation. There were significant decreases in heart rate, PaO2 and respiratory rate. There was no significant change in mean arterial pressure even at the highest (320 micrograms/kg) dose. To examine the ability of an alpha 2 adrenergic antagonist to reverse the effects of dexmedetomidine, 5 rabbits initially received 320 micrograms/kg of dexmedetomidine as described above. Seven minutes after completion of the infusion, 900 micrograms/kg of the alpha 2 adrenergic antagonist, idazoxan, was administered. This resulted in a prompt and sustained reversal of the hypercarbia and sedation produced by the dexmedetomidine.
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PMID:Ventilatory, hemodynamic and sedative effects of the alpha 2 adrenergic agonist, dexmedetomidine. 168 46

Dexmedetomidine is a highly selective and specific alpha(2)-adrenergic agonist, with sedative, analgesic, and sympatholytic activities. The aim of the present study was to define the effects of DMED in respiratory mechanics in normal rats. In addition, lung morphometry was studied to determine whether the physiological changes reflected underlying morphological changes defining the sites of action of dexmedetomidine. Arterial blood gases were also determined. Twelve adult Wistar rats were randomly assigned to two groups of six animals each: PENTO and DMED. In PENTO group animals were sedated (diazepam, 5mg, i.p.) and anaesthetised with pentobarbital sodium (20mgkg(-1) i.p.). The rats of the DMED group received dexmedetomidine (250mugkg(-1) i.p. followed by intravenous infusion of 0.5mugkg(-1)h(-1)). In spontaneously breathing rats, minute ventilation, respiratory frequency, and neuromuscular inspiratory drive were lower in dexmedetomidine group, which also presented hypercapnia, whereas tidal volume, inspiratory, expiratory, and total respiratory cycle times were higher in dexmedetomidine group compared to the PENTO group. During mechanical ventilation, respiratory mechanical parameters were similar in both groups. These findings were supported by the absence of histological changes. In conclusion, under the conditions studied, dexmedetomidine did not change respiratory mechanical parameters and lung histology, but induced ventilatory depression.
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PMID:Effects of dexmedetomidine on respiratory mechanics and control of breathing in normal rats. 1652 48