Anesthesia and analgesia
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Anesthesia and analgesia · Mar 2005
Case ReportsHyperkalemic cardiac arrest after cardiopulmonary bypass in a child with unsuspected duchenne muscular dystrophy.
Adverse reactions to volatile anesthetics and depolarizing muscle relaxants can occur in patients with Duchenne muscular dystrophy (DMD) resulting in acute rhabdomyolysis and hyperkalemia. We report a case of hyperkalemic cardiac arrest after cardiac surgery using cardiopulmonary bypass in a child with unsuspected DMD. ⋯ Genetic testing confirmed the diagnosis of DMD. We recommend a thorough preoperative investigation, including creatine kinase estimation, in children with a history of unexplained motor delay.
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Anesthesia and analgesia · Mar 2005
Perineural resiniferatoxin prevents hyperalgesia in a rat model of postoperative pain.
Resiniferatoxin (RTX) is a vanilloid agonist with a unique spectrum of activities. Vanilloids bind to the transient receptor potential ion channel subtype 1, a nonselective cation ionophore important in the integration of different noxious signals. Vanilloid agonists selectively decrease sensitivity to noxious stimuli. ⋯ Two hours after incision, the withdrawal threshold was 51 mN without and 456 mN with RTX (P < 0.0001). RTX also prevented the incision-induced decrease in struggle threshold and abolished the pain behavior associated with weight bearing. We conclude that RTX provides a type of neural blockade when postoperative pain is abolished and that nonpainful sensations and motor functions are preserved.
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Anesthesia and analgesia · Mar 2005
Enantioselective actions of bupivacaine and ropivacaine on coronary vascular resistance at cardiotoxic concentrations.
The main concern with the use of the long-acting local anesthetics bupivacaine and ropivacaine is inadvertent IV injection, which exposes the heart to toxic drug concentrations. We tested the hypothesis that these chiral anesthetics exert enantioselective actions on coronary vascular tone, the regulation of which does not involve voltage-gated Na(+) channels. Coronary perfusion pressure (CPP) was continuously measured in isolated hearts perfused via the aorta at a constant flow rate. ⋯ We also showed that the putative uncoupler bupivacaine did not depolarize mitochondria in intact ventricular myocytes. In conclusion, the long-acting local anesthetics have enantioselective actions on coronary resistance vessels. Racemic bupivacaine and R(+)-bupivacaine are coronary vasodilators, whereas S(-)-bupivacaine, S(-)-ropivacaine and, to a lesser extent, R(+)-ropivacaine all induce coronary vasoconstriction.
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Anesthesia and analgesia · Mar 2005
Dominance of the hand does not change the phonomyographic measurement of neuromuscular block at the adductor pollicis muscle.
Phonomyography (PMG) is a novel method to determine neuromuscular blockade (NMB) with high sensitivity and applicability at all muscles. The adductor pollicis muscle has long been used in research and clinical practice as reference for neuromuscular monitoring. The goal of our study was to compare PMG signals (train-of-four [TOF] ratios and T(1)/T(0) values) from both hands of the same patient to investigate the influence of hand dominance on neuromuscular monitoring. ⋯ Agreement was excellent with a bias of -0.57% and limits of agreement of -17.9% to 16.7% (dominant - nondominant hand). This study shows minimal bias, good correlation and no statistical difference when NMB is monitored at both the dominant and nondominant adductor pollicis muscles. Both hands could be used interchangeably to assess NMB at the adductor pollicis muscle.
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Anesthesia and analgesia · Mar 2005
Case ReportsTransdermal buprenorphine for treating nociceptive and neuropathic pain: four case studies.
The use of opioids for treating neuropathic pain is controversial, and some studies have indicated that neuropathic pain may be relatively insensitive to typical mu-opioid analgesics such as morphine. However, it is becoming clear that different opioids produce analgesia by affecting different pain pathways. We present two cases of neuropathic pain and two cases of nociceptive pain with a significant neuropathic component that were treated with transdermal buprenorphine. In each case, sufficient pain relief was obtained and no problems were encountered in switching from prior analgesic therapy with larger doses of other opioids.