Anesthesia and analgesia
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Anesthesia and analgesia · Oct 2008
The inhibition of human neutrophil phagocytosis and oxidative burst by tricyclic antidepressants.
Tricyclic antidepressants are being investigated as long-acting analgesics for topical application in wounds or IV for postoperative pain relief. However, it remains unclear if tricyclic antidepressants affect the host defense and if reported toxic effects on neutrophils are of relevance in this setting. We therefore investigated the effects of amitriptyline, nortriptyline, and fluoxetine on human neutrophil phagocytosis, oxidative burst, and neutrophil toxicity in a human whole blood model. ⋯ Phagocytosis and intracellular host defense are largely unaffected by antidepressants in concentrations of 10(-4) M and below. Our results confirm that antidepressants are highly toxic to neutrophils in millimolar concentrations. The neurotoxic effects and clinical side effects, but not effects on neutrophil functions, therefore, are likely to be the limiting factors in using antidepressants as analgesics.
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Anesthesia and analgesia · Oct 2008
Spatial memory is intact in aged rats after propofol anesthesia.
We have previously demonstrated that aged rats have persistent impairment of spatial memory after sedation with nitrous oxide or general anesthesia with isoflurane-nitrous oxide. Propofol has different receptor mechanisms of action and a favorable short-term recovery profile, and it has been proposed that propofol is devoid of enduring effects on cognitive performance. No studies have investigated this question in aged subjects, however, so we designed an experiment to examine the long-term effects of propofol anesthesia on spatial working memory. ⋯ In aged rats, propofol anesthesia is devoid of the persistent memory effects observed with other general anesthetics in this model. Thus, while it appears that the state of general anesthesia is neither necessary nor sufficient for development of postanesthetic memory impairment, the choice of anesthetics may play a role in late cognitive outcome in the aged.
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Anesthesia and analgesia · Oct 2008
Percutaneous pulsed radiofrequency reduces mechanical allodynia in a neuropathic pain model.
Neuropathic pain is a result of a primary lesion or dysfunction of the peripheral or central nervous system, and its treatment is challenging. Animal models have been helpful in understanding mechanisms of neuropathic pain and in developing new treatment strategies. In this study, we examined the effect of percutaneous pulsed radiofrequency (PRF), which is a minimally invasive pain treatment method, on mechanical allodynia in a neuropathic pain rat model. ⋯ Percutaneous PRF is an effective treatment option in the NP pain model, and further studies are needed to clarify its underlying mechanisms of action.
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Anesthesia and analgesia · Oct 2008
Pharmacokinetics of levobupivacaine (2.5 mg/kg) after caudal administration in children younger than 3 years.
Caudal administration of levobupivacaine (2.5 mg/kg) in children is used frequently in some hospitals. However, no reports of levobupivacaine concentrations have been published with this dosing scheme. We report the results of a study on the pharmacokinetics of levobupivacaine (2.5 mg/kg) after caudal administration in children younger than 3 yr. ⋯ The highest Cmax reached in this study was close to the toxic threshold of adult patients. Although no adverse events have been reported, care must be taken, especially in small infants, after caudal administration of levobupivacaine (2.5 mg/kg).
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Anesthesia and analgesia · Oct 2008
A new curved laryngoscope blade for routine and difficult tracheal intubation.
We have designed a new curved laryngoscope blade based on a new concept of reversing the peardrop phenomenon to facilitate a view of the larynx sufficient for intubation in a greater variety of patients than the current Macintosh blade affords. The new design has a bifid tip and S-shaped spatula to exert more effective pressure in the vallecula area, elevate the epiglottis and change directions of the forces on the tongue to prevent posteroinferior displacement of the compressed tongue in the submandibular space during laryngoscopy. ⋯ Our results confirm that the new blade provides a laryngeal view sufficient to accomplish intubation by compressing the root of the tongue in an anterocephalad direction in the submandibular space and elevating the epiglottis effectively in patients with or without unanticipated difficult airway. The new curved blade can also effectively move the U-shaped epiglottis out of the laryngeal view to facilitate intubation in pediatric patients aged 2 mo-13 yr.