Pain
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Comparative Study
Contributions of the anterior cingulate cortex and amygdala to pain- and fear-conditioned place avoidance in rats.
The pain experience includes a sensory-discriminative and an affective-emotional component. The sensory component of pain has been extensively studied, while data about the negative affective component of pain are quite limited. The anterior cingulate cortex (ACC), and amygdala are thought to be key neural substrates underlying emotional responses. ⋯ However, the decrease in the magnitude of S-CPA occurred only in the amygdala, but not ACC lesioned animals. Neither ACC nor amygdala lesion significantly changed formalin-induced acute nociceptive behaviors. These results suggest that the amygdala is involved in both pain- and fear-related negative emotion, and the ACC might play a critical role in the expression of pain-related negative emotion.
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Comparative Study
Site 1 sodium channel blockers prolong the duration of sciatic nerve blockade from tricyclic antidepressants.
Many recent reports in the literature address the local anesthetics efficacy of tricyclic antidepressants (TCAs). Here we investigated whether nerve block from TCAs is prolonged by site 1 sodium channel blockers such as tetrodotoxin and saxitoxin, which are known to prolong block from conventional local anesthetics. Tetrodotoxin and saxitoxin greatly prolonged block from TCAs. ⋯ Systemic (subcutaneous) delivery of tetrodotoxin or amitriptyline did not result in prolongation of block from the other class of drug injected at the sciatic nerve. In TCA-containing formulations, motor blockade was consistently longer than thermal nociceptive block; motor blockade was also prolonged by tetrodotoxin and saxitoxin. In summary site 1 sodium channel blockers prolong the duration of TCAs via a locally mediated mechanism.
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Randomized Controlled Trial Comparative Study Clinical Trial
A randomized clinical trial of the effectiveness of a scheduled oral analgesic dosing regimen for the management of postoperative pain in children following tonsillectomy.
The purpose of this study was to determine whether around-the-clock (i.e. ATC) dosing of acetaminophen with codeine, with or without nurse coaching, compared to standard care with as needed (i.e. PRN) dosing: reduced children's reports of pain intensity with and without swallowing; increased pain relief, and increased analgesic consumption. ⋯ No significant differences were found in the amount of nausea and vomiting among the three groups. Scheduled dosing of acetaminophen with codeine did not provide adequate pain relief for children following tonsillectomy. Nurse coaching does not increase parent's adherence with an ATC dosing schedule.
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Randomized Controlled Trial Multicenter Study Comparative Study Clinical Trial
Relative analgesic potency of fentanyl and sufentanil during intermediate-term infusions in patients after long-term opioid treatment for chronic pain.
Sufentanil, a potent mu-opioid agonist, historically has not been been given systemically to treat chronic pain. An implantable, fixed-rate osmotic pump that delivers sufentanil subcutaneously is being developed for this purpose. In that transdermal fentanyl may be a useful intermediary to estimate the appropriate sufentanil dose before implant, accurate information is needed about the relative analgesic potency of sufentanil and fentanyl during continuous infusion. ⋯ For the remaining 41 patients, target concentrations associated with adequate analgesia were achieved for both sufentanil and fentanyl. The median value for the equianalgesic concentration ratio (steady-state fentanyl infusion to steady-state sufentanil infusion) was 7.5; mean potency ratio was 7.44 (95% confidence interval 6.8-8.2). During titrated, intermediate-term infusions in patients previously treated with opioids for chronic pain, sufentanil is approximately 7.5 times as potent as fentanyl.
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Randomized Controlled Trial Comparative Study Clinical Trial
Imagery reduces children's post-operative pain.
This un-blinded experimental study investigated the effectiveness of imagery, in addition to routine analgesics, in reducing tonsillectomy and/or adenoidectomy pain and anxiety after ambulatory surgery (AS) and at home. Seventy-three children, aged 7-12, were recruited from five AS settings. Thirty-six children randomly assigned to the treatment group watched a professionally developed videotape on the use of imagery and then listened to a 30-min audio tape of imagery approximately 1 week prior to surgery (T1). ⋯ When controlling for trait anxiety, a two-way RM MANCOVA indicated no significant group differences in combined opioid and non-opioid use between the groups, or between times. Appropriately trained health care providers should use imagery to reduce post-operative pain following tonsillectomy and/or adenoidectomy in AS. Teaching parents about adequate home administration of analgesics may increase the effectiveness of imagery at home.