Anesthesia and analgesia
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Anesthesia and analgesia · Dec 2011
ReviewPharmacogenomics of β-adrenergic receptor physiology and response to β-blockade.
Myocardial β-adrenergic receptors (βARs) are important in altering heart rate, inotropic state, and myocardial relaxation (lusitropy). The β1AR and β2AR stimulation increases cyclic adenosine monophosphate concentration with the net result of myocyte contraction, whereas β3AR stimulation results in decreased inotropy. Downregulation of β1ARs in heart failure, as well as an increased β3AR activity and density, lead to decreased cyclic adenosine monophosphate production and reduced inotropy. ⋯ Although βAR SNPs may not directly cause disease, they appear to be risk factors for, and modifiers of, disease and the response to stress and drugs. In the perioperative setting, this has specifically been demonstrated for the Arg389Gly β1AR polymorphism with which patients with the Gly variant had a higher incidence of adverse perioperative events. Knowing that genetic variants play an important role, perioperative medicine will likely change from simple therapeutic intervention to a more personalized way of adrenergic receptor modulation.
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Anesthesia and analgesia · Dec 2011
ReviewBrief preoperative smoking abstinence: is there a dilemma?
The concern that stopping smoking shortly (<8 weeks) before surgery increases postoperative pulmonary complications poses a barrier to tobacco use interventions in surgical patients. We show how this concern arose from a misinterpretation of initial studies and has remained in the medical literature despite the accumulation of later evidence. The persistence of unsubstantiated concepts is not uncommon and can have a significant impact on medical practice. Although it may take several weeks to derive pulmonary benefit from quitting, fear of an increase in pulmonary complications should not be a barrier for clinicians to help their patients quit smoking at any time before surgery.
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Anesthesia and analgesia · Dec 2011
Randomized Controlled Trial Comparative StudyDistal tourniquet or leg position after injection enhances the efficacy of sciatic nerve blockade by the popliteal approach.
In this study, we hypothesized that leg positioning and distal tourniquet application, when compared with neutral positioning of the leg, alters the efficacy of sciatic nerve block performed by the double-stimulation technique. ⋯ Similar beneficial effects might be reached with the application of a distal tourniquet during injection or elevating the patient's leg turned supine immediately after sciatic nerve block with a popliteal approach by a double-injection technique. We suggest that using the leg-up position or application of a distal tourniquet for sciatic nerve block may lead to a more proximal distribution of the local anesthetic and may result in a faster onset of sensory and motor blocks as well as longer duration of blockade.