Anesthesiology
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Randomized Controlled Trial Comparative Study Clinical Trial
Comparable postoperative pulmonary atelectasis in patients given 30% or 80% oxygen during and 2 hours after colon resection.
High concentrations of inspired oxygen are associated with pulmonary atelectasis but also provide recognized advantages. Consequently, the appropriate inspired oxygen concentration for general surgical use remains controversial. The authors tested the hypothesis that atelectasis and pulmonary dysfunction on the first postoperative day are comparable in patients given 30% or 80% perioperative oxygen. ⋯ Lung volumes, the incidence and severity of atelectasis, and alveolar gas exchange were comparable in patients given 30% and 80% perioperative oxygen. The authors conclude that administration of 80% oxygen in the perioperative period does not worsen lung function. Therefore, patients who may benefit from generous oxygen partial pressures should not be denied supplemental perioperative oxygen for fear of causing atelectasis.
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Randomized Controlled Trial Comparative Study Clinical Trial
Postoperative pain facilitates nonthermoregulatory tremor.
Spontaneous tremor is relatively common in normothermic patients after operation and has been attributed to many causes. The hypothesis that nonthermoregulatory shivering-like tremor is facilitated by postoperative pain was tested. In addition, the effects of intravenous lidocaine on nonthermoregulatory tremor were evaluated. ⋯ Intra-articular, but not intravenous, lidocaine reduced surgical pain and prevented nonthermoregulatory shivering. Therefore, these data indicate that postoperative pain facilitates nonthermoregulatory shivering.
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Randomized Controlled Trial Clinical Trial
Effect of epinephrine on lidocaine clearance in vivo: a microdialysis study in humans.
Local anesthetic nerve block prolonged by epinephrine is thought to result from local vasoconstriction and consequent decreased local anesthetic clearance from the injection site. However, no study has yet confirmed this directly in humans by measuring tissue concentrations of local anesthetic over time. In addition, recent studies have shown that the alpha2-adrenergic receptor agonist, clonidine, also prolongs nerve block without altering local anesthetic clearance. Because epinephrine is also an alpha2-adrenergic receptor agonist, it is possible that epinephrine prolongs local anesthetic block by a pharmacodynamic mechanism and not a pharmacokinetic one. This study was designed to address this issue. ⋯ Although epinephrine activates alpha2-adrenergic receptors, its mechanism for prolonging the duration of local anesthetic block rests on its ability to decrease local anesthetic clearance and not on a pharmacodynamically mediated potentiation of local anesthetic effect.
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Randomized Controlled Trial Multicenter Study Clinical Trial
Effect of mivazerol on perioperative cardiac complications during non-cardiac surgery in patients with coronary heart disease: the European Mivazerol Trial (EMIT).
Mivazerol is a drug with alpha2-agonist properties that reduces post-ganglionic noradrenaline availability and spinal efferent sympathetic output. ⋯ The alpha2-adrenergic agonist, mivazerol, did not alter the rates of myocardial infarction or cardiac death in patients with known coronary heart disease undergoing noncardiac surgery. However, it may have protected patients undergoing vascular surgery from further coronary events, and a specific study of such patients is now indicated.
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Randomized Controlled Trial Comparative Study Clinical Trial
Randomized trial of hypotensive epidural anesthesia in older adults.
Data are sparse on the incidence of postoperative cognitive, cardiac, and renal complications after deliberate hypotensive anesthesia in elderly patients. ⋯ Elderly patients can safely receive controlled hypotensive epidural anesthesia with this protocol. There was no evidence of greater risks, or early benefits, with the use of the more markedly hypotensive range.