Anesthesia and analgesia
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Anesthesia and analgesia · May 2007
Comparative Study Clinical TrialThe influence of stellate ganglion transcutaneous electrical nerve stimulation on signal quality of pulse oximetry in prehospital trauma care.
Accurate monitoring of the peripheral arterial oxygen saturation has become an important tool in the prehospital emergency medicine. This monitoring requires an adequate plethysmographic pulsation. Signal quality is diminished by cold ambient temperature due to vasoconstriction. Blockade of the stellate ganglion can improve peripheral vascular perfusion and can be achieved by direct injection or transcutaneous electrical nerve stimulation (TENS) stimulation. We evaluated whether TENS on the stellate ganglion would reduce vasoconstriction and thereby improve signal detection quality of peripheral pulse oximetry. ⋯ The data indicate that blockade of the stellate ganglion with TENS improves signal quality of pulse oximeters in the prehospital setting.
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Anesthesia and analgesia · May 2007
Comparative StudyGender differences in stroke risk among the elderly after coronary artery surgery.
Previous studies have shown that women are at higher risk than men for stroke after coronary artery bypass graft (CABG) surgery, but gender differences in systemic atherosclerosis have not been studied adequately. We investigated gender differences in the incidence of craniocervical and ascending aortic atherosclerosis and other risk factors for stroke in elderly patients (age > or =60 yr) undergoing CABG surgery. ⋯ These data suggest that men are more likely than women to have risk factors for stroke, including severe carotid artery stenosis, severe aortic atherosclerosis, and peripheral vascular disease. The rates of prior cerebral infarction and preoperative cognitive impairment were similar between genders.
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Anesthesia and analgesia · May 2007
Comparative StudyThe effects of systemic lidocaine on airway tone and pulmonary function in asthmatic subjects.
To prevent reflex-induced bronchoconstriction in patients with asthma, local anesthetics are commonly administered by aerosol or IV as adjunct medication. Lidocaine attenuates responsiveness to a neurally active stimulus that increases tone, but there is scant information about the effect of lidocaine on baseline airway tone. Therefore we examined the effects of IV lidocaine on baseline airway tone in asthmatic subjects. ⋯ Lidocaine, which reduces airway responsiveness to drugs that cause bronchospasm through sensory nerve activation, did not reduce baseline airway tone. Instead, even when administered IV, lidocaine significantly increased airway tone and caused airway narrowing. Therefore, while the administration of lidocaine can prevent intubation-induced bronchospasm, the airways should be constantly monitored by auscultation even during IV lidocaine administration.
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Anesthesia and analgesia · May 2007
Comparative StudyPerineural resiniferatoxin prevents the development of hyperalgesia produced by loose ligation of the sciatic nerve in rats.
The vanilloid receptors (TRPV1) are found in peripheral nerve fibers; their stimulation by capsaicin leads to release of calcitonin gene-related peptide and other neuropeptides participating in neuroinflammation. On the other hand, various inflammatory mediators, released after nerve damage, can activate or sensitize the TRPV1 receptors. These findings together suggest a protective effect of TRPV1 receptor blockade in neuropathy. In the present study, we tested the hypothesis that perineural resiniferatoxin (RTX) can prevent the development of hyperalgesia caused by placing loosely constrictive ligatures around the sciatic nerve. ⋯ Perineural RTX prevents the development of neuropathy caused by placing loosely constrictive ligatures on the sciatic nerve. Perioperative use of drugs acting via the TRPV1 receptors may hold the promise for preventing neuropathic pain after surgery on peripheral nerves.
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Anesthesia and analgesia · May 2007
Comparative StudyUltrasound using the transverse approach to the lumbar spine provides reliable landmarks for labor epidurals.
Ultrasound imaging of the spine has recently been proposed to facilitate identification of the epidural space. In this study, we assessed the accuracy and precision of the transverse approach, using a "single-screen" method, to facilitate labor epidurals. ⋯ We found a good level of success in the ultrasound-determined insertion point, and very good agreement between UD and ND. This suggests that our proposed ultrasound single-screen method, using the transverse approach, can be a reliable guide to facilitate labor epidural insertion.