Anesthesiology
-
Randomized Controlled Trial Comparative Study Clinical Trial
Spontaneous ventilation with halothane in children. A comparative study between endotracheal tube and laryngeal mask airway.
It has been reported that, in children breathing spontaneously via an endotracheal tube, halothane depresses ventilation with paradoxic inspiratory movement. Endotracheal tubes have a higher airflow resistance than do laryngeal mask airways (LMAs). Therefore, the aim of this study was to compare spontaneous ventilation via the LMA with that via the endotracheal tube in children anesthetized with halothane. ⋯ In 6-24-month-old children anesthetized with halothane, paradoxic inspiratory movement is less when breathing through an LMA than through an endotracheal tube.
-
Randomized Controlled Trial Clinical Trial
Enzymatic antagonism of mivacurium-induced neuromuscular blockade by human plasma cholinesterase.
Mivacurium chloride is a bis-benzylisoquinolinium nondepolarizing neuromuscular blocking agent, hydrolyzed by butyrylcholinesterase (PCHE). The dose-response relationships for PCHE after mivacurium have not been studied. Therefore, this study was designed to establish dose-response relationships for PCHE as an antagonist of mivacurium-induced neuromuscular blockade. ⋯ Administration of exogenous PCHE equivalent to activity present in 25 ml/kg of human plasma (in a 65-kg patient, this dose is equivalent to PCHE activity of 1,625 ml of adult human plasma) resulted in reliable antagonism of mivacurium-induced neuromuscular blockade. Nevertheless, because of the prohibitive cost of this compound, this reversal modality is unlikely to have a routine practical application at this time.
-
Review Case Reports
Severe neurologic deficit after nitrous oxide anesthesia.
-
In patients with acute respiratory distress syndrome (ARDS), the ventilatory approach is based on tidal volume (VT) of 10-15 ml/kg and positive end-expiratory pressure (PEEP). To avoid further pulmonary injury, decreasing VT and allowing PaCO2 to increase (permissive hypercapnia) has been suggested. Effects of 10 cmH2O of PEEP on respiratory mechanics, hemodynamics, and gas exchange were compared during mechanical ventilation with conventional (10-15 ml/kg) and low (5-8 ml/kg) VT. ⋯ Although PEEP induced alveolar hyperinflation in most patients during mechanical ventilation with conventional VT, at low VT, there appeared to be a significant alveolar collapse, and PEEP was able to expand these units, improving gas exchange and hemodynamics.
-
Several parameters derived from the multivariate electroencephalographic (EEG) signal have been used to characterize the effects of opioids on the central nervous system. These parameters were formulated on an empirical basis. A new statistical method, semilinear canonical correlation, has been used to construct a new EEG parameter (a certain combination of the powers in the EEG power spectrum) that correlates maximally with the concentration of alfentanil at the effect site. To date, this new canonical univariate parameter (CUP) has been tested only in a small sample of subjects receiving alfentanil. ⋯ Although the CUP was originally designed and tested using alfentanil, we have proven it to be a general measure of opioid effect on the EEG.