Articles: general-anesthesia.
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Randomized Controlled Trial Comparative Study Clinical Trial
Changes in haemodynamic variables during transurethral resection of the prostate: comparison of general and spinal anaesthesia.
We have compared changes in haemodynamic variables before and during transurethral resection of the prostate in 22 patients under general or spinal anaesthesia. In the general anaesthetic group there was a significant decrease in cardiac output (mean 32% (SEM 5%)) and mean arterial pressure (14% (3%)) after induction of anaesthesia and a significant decrease (27% (3%)) in heart rate before the start of resection. ⋯ We conclude that with both these anaesthetic techniques the greatest changes in haemodynamic variables occurred shortly after induction, and that these changes were greater during general than spinal anaesthesia. The resection period was not associated with significant haemodynamic changes.
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Randomized Controlled Trial Comparative Study Clinical Trial
The laryngeal mask airway and positive-pressure ventilation.
The utility of the laryngeal mask airway during positive-pressure ventilation has yet to be determined. Our study was designed to assess whether significant leaks occurred with positive-pressure ventilation and if leaks were associated with gastroesophageal insufflation. ⋯ Ventilation using the laryngeal mask appears to be adequate if airway resistance and pulmonary compliance are normal. Gastroesophageal insufflation of air will become a problem in the presence increased ventilation pressure.
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Rev Esp Anestesiol Reanim · Mar 1994
Randomized Controlled Trial Comparative Study Clinical Trial[Premedication with clonidine in the neurosurgical patient: sedation, anesthetic requirements and hemodynamic perfusion].
To analyze the effect of premedication with clonidine on postoperative sedation, anesthetic requirements and hemodynamic repercussions in patients undergoing craniotomy due to supratentorial intracranial pathology. ⋯ Premedication of neurosurgical patients with clonidine offers no advantages over lorazepam with respect to sedation. Nevertheless, clonidine may offer advantages with respect to the amount of alfentanyl required and attenuation of perioperative adrenergic response.
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Rev Esp Anestesiol Reanim · Mar 1994
Comment Randomized Controlled Trial Comparative Study Clinical Trial[Oral premedication with clonidine in patients undergoing coronary revascularization surgery].
To analyze the effect of premedication with clonidine on level of sedation, anesthetic requirements and hemodynamic repercussions in patients undergoing coronary revascularization. ⋯ Use of clonidine in the type of patient studied does not improve the level of sedation over that achieved with lorazepam. Fentanyl requirements decreased with clonidine. With respect to hemodynamic profile, systemic vascular resistance fell in the clonidine group after removal of ECC, and thus this drug offers no advantages for routine premedication.
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Impaired gas exchange is a major complication after cardiac surgery with the use of extracorporeal circulation. Blood gas analysis gives little information on underlying mechanisms, in particular if the impairment is multifactorial. In the current study we used the multiple inert gas technique with recordings of hemodynamics to analyze the separate effects of intrapulmonary shunt (QS/QT), ventilation-perfusion (VA/Q) mismatch, and low mixed venous oxygen tension on arterial oxygenation during cardiac surgery. ⋯ QS/QT is a major component of impaired gas exchange before, during, and after cardiac surgery. QS/QT increases after induction of general anesthesia, probably because of development of atelectasis. After separation from extracorporeal circulation, accumulation of extravascular lung water or further collapse of lung tissue may aggravate QS/QT. Postoperatively, oxygenation improves, possibly because of recruitment of previously nonventilated alveoli or resolution of extravascular lung water. During spontaneous breathing, additional mechanisms such as altered mechanics of the chest, perfusion of low-VA/Q regions, and decreased mixed venous oxygen tension may contribute to impaired gas exchange.