Pain
-
Randomized Controlled Trial Clinical Trial
Analgesic profile of peroral and topical ketoprofen upon low pH-induced muscle pain.
Topical analgesics are widely marketed for treatment of muscle and joint pain. We have recently developed a model of muscle pain and have used this model to evaluate the efficacy of commercially available topical and peroral ketoprofen in order to evaluate the time- and dose-dependence of analgesia. In the present study, we examined the dose- (0, 50, and 100 mg) and time-dependence (hourly to 8 h) of commercially available peroral and topical ketoprofen. ⋯ The apparent analgesia was rapid to develop but transient and pain ratings increased back to baseline values within 3 h for the 100 mg dose and within 2 h for the 50 mg dose. This data suggests that topical application of commercial gel-based systems does not provide long-lasting analgesia in the muscle when compared to perorally-dosed ketoprofen. In addition, the data show that even doses of 100 mg peroral ketoprofen do not provide complete relief of muscle pain.
-
Randomized Controlled Trial Clinical Trial
Response expectancies in placebo analgesia and their clinical relevance.
Response expectancies have been proposed as the major determinant of placebo effects. Here we report that different expectations produce different analgesic effects which in turn can be harnessed in clinical practice. Thoracotomized patients were treated with buprenorphine on request for 3 consecutive days, together with a basal intravenous infusion of saline solution. ⋯ Overall, after 3 days of placebo infusion, the first group received 11.55 mg of buprenorphine, the second group 9.15 mg, and the third group 7.65 mg. Despite these dose differences, analgesia was the same in the three groups. These results indicate that different verbal instructions about certain and uncertain expectations of analgesia produce different placebo analgesic effects, which in turn trigger a dramatic change of behaviour leading to a significant reduction of opioid intake.
-
Randomized Controlled Trial Clinical Trial
'Balanced analgesia' in the perioperative period: is there a place for ketamine?
We investigated whether intraoperative 'subanesthetic doses' of ketamine have a postoperative anti-hyperalgesic and an analgesic effect and which is the preferential route of administration, either systemic (intravenous, i.v.) or epidural. One hundred patients scheduled for rectal adenocarcinoma surgery under combined epidural/general anesthesia were included. Before skin incision all the patients received an epidural bolus followed by an infusion of continuous bupivacaine/sufentanil/clonidine mixture. ⋯ These patients reported significantly less residual pain until the sixth postoperative month. These observations support the theory that subanesthetic doses of i.v. ketamine (0.5 mg/kg bolus followed by 0.25 mg/kg per h) given during anesthesia reduce wound hyperalgesia and are a useful adjuvant in perioperative balanced analgesia. Moreover, they show that the systemic route clearly is the preferential route.
-
Randomized Controlled Trial Clinical Trial
Muscle pain inhibits cutaneous touch perception.
The processing of noxious and non-noxious sensations differs between chronic pain syndromes, and we believe that studies of sensory processing in the presence of pain will help to clarify the aetiology of the conditions. Here we measured in humans the threshold-level mechanosensitivity in tonic experimental muscle pain. ⋯ Comparing our findings to results obtained with other pain models, all classes of nociceptors do not seem to have the same effect on cutaneous mechanosensitivity. The observed threshold-level hypoesthesia is consistent with the hypothesis that the increased mechanical thresholds found in clinic cases of temporomandibular disorders and cervicobrachialgia are a direct result of the activation of muscle nociceptors.
-
Randomized Controlled Trial Clinical Trial
The effects of failure feedback and pain-related fear on pain report, pain tolerance, and pain avoidance in chronic low back pain patients.
The aim of this study was to investigate the influence of non-pain-related failure experiences and pain-related fear on pain report, pain tolerance and pain avoidance in chronic low back pain (CLBP) patients. Moreover, the mediating and moderating role of negative affectivity (trait-NA) in the relationship between failure experiences and pain was examined. Seventy-six patients were divided into high and low pain-related fear groups and within each group they were randomly assigned to the failure or success feedback condition. ⋯ Pain-related fear did not predict pain avoidance when pre-lifting pain and gender were controlled for. Finally, pre-lifting pain turned out to be the strongest predictor with regard to all pain measures. The role of pain-related fear and unexpected findings with regard to feedback are discussed as well as some clinical implications.