Articles: general-anesthesia.
-
Randomized Controlled Trial Multicenter Study Comparative Study Clinical Trial
Intramuscular dexmedetomidine as premedication for general anesthesia. A comparative multicenter study.
Dexmedetomidine is a new potent and selective alpha 2-agonist that might prove useful as a preanesthetic agent. ⋯ The results suggest that pretreatment with a single intramuscular injection of 2.5 micrograms/kg dexmedetomidine is efficacious, but significantly increases the incidence of intraoperative hypotension and bradycardia in ASA physical status 1 or 2 patients.
-
Cytokines released in response to stress may have a profound impact on circulatory stability. There is no information on the effect of general anesthesia alone on plasma cytokine levels and little information on cytokine release following surgery. Plasma cytokine levels and hemodynamic parameters were measured during anesthesia and abdominal surgery under sterile and nonpyrogenic conditions in seven pigs anesthetized with ketamine and pentobarbital. ⋯ Heart rate was unchanged during the experiment, and central venous pressure decreased after endotoxin (P < .05). There were no increases in TNF or IL-6 (using a low sensitivity assay) with anesthesia alone or following IM with shock, but both increased after endotoxin administration (P < .05); using a high sensitivity assay, IL-6 did not change during anesthesia alone but did increase fivefold following IM with shock (P < .05) and 50-fold following endotoxin administration (P < .05). We conclude that in a porcine model under sterile and nonpyrogenic conditions, prolonged anesthesia does not increase plasma cytokine levels.(ABSTRACT TRUNCATED AT 250 WORDS)
-
Mivacurium is a potent nondepolarising neuromuscular blocking agent which is structurally related to the benzylisoquinolinium compound, atracurium. Mivacurium has a short duration of action due to its rapid elimination by plasma cholinesterase. When administered to essentially healthy adult patients receiving nitrous oxide-narcotic anaesthesia, the recommended intubating dose (2 x ED95) usually provides clinically effective neuromuscular block for approximately 15 to 20 minutes and spontaneous recovery is 95% complete within about 25 to 30 minutes. ⋯ In summary, a single bolus dose of mivacurium can be recommended for use in adult and paediatric patients undergoing nonemergency tracheal intubation and/or during short surgical procedures. For maintenance of neuromuscular block, mivacurium can be administered as multiple bolus doses or as a continuous infusion. In particular, the lack of a significant cumulative effect renders the drug suitable for the maintenance of neuromuscular blockade during extended surgical procedures of unpredictable length.
-
Comparative Study Clinical Trial Controlled Clinical Trial
Epidural morphine reduces the risk of postoperative myocardial ischaemia in patients with cardiac risk factors.
Perioperative myocardial ischaemia is a predictor of postoperative cardiac morbidity (PCM). Epidural anaesthesia and adequate perioperative analgesia have been shown to improve myocardial oxygen dynamics due to interruption of pain and sympathetic pathways. The aim of the present study was to compare the incidence of ischaemia after either general anaesthesia followed by parenteral analgesia with morphine or combined epidural/general anaesthesia followed by analgesia with epidural morphine. ⋯ Forty-two percent of ischaemic episodes were associated with a heart rate > 100 bpm, or an increase of 20% over the baseline heart rate. We conclude that epidural anaesthesia/analgesia reduces but does not eliminate the risk of myocardial ischaemia and tachyarrhythmia. We were unable to determine any associated reduction in the risk of PCM.