Pain
-
Temporal summation of pain occurs when repeated stimuli become increasingly painful in spite of unchanged stimulus intensity. Summation can be quantified as the difference in pain between the first and the last stimulus in a train of stimuli. The aim of the study was to compare temporal summation of pain in normal skin with summation of pain in skin with primary and secondary hyperalgesia evoked by a heat injury. ⋯ Temporal summation at high stimulus intensities was more pronounced than at lower intensities (P < 0.0002). We found no correlation between either temporal summation and area of secondary hyperalgesia, or temporal summation and pain intensity during the induction of heat injury. We conclude that the development of primary and secondary mechanical hyperalgesia after heat injury in man was not associated with changes in temporal summation of painful electrical stimuli.
-
Spinal cord stimulation reduces pain of critical ischaemia in patients with severe inoperable coronary artery and peripheral vascular disease by increasing microvascular flow. Patients with cardiac pacemaker may be denied a spinal cord stimulator (SCS) implant because of the risk of compromising pacemaker function by inhibition or reversion to asynchronous noise-pacing mode. We describe the management of a patient with an SCS implant for lower limb ischaemia who required a pacemaker. We suggest that with modern pacemakers it is safe to implant a spinal cord stimulator simultaneously with a pacemaker provided adequate precautions are taken to prevent interdevice interference.
-
Fillingim and Maixner (Fillingim, R. B. and Maixner, W., Pain Forum, 4(4) (1995) 209-221) recently reviewed the body of literature examining possible sex differences in responses to experimentally induced noxious stimulation. Using a 'box score' methodology, they concluded the literature supports sex differences in response to noxious stimuli, with females displaying greater sensitivity. ⋯ Given the estimated effect size of 0.55 threshold or 0.57 for tolerance, 41 subjects per group are necessary to provide adequate power (0.70) to test for this difference. Of the 34 studies reviewed by Fillingim and Maixner, only seven were conducted with groups of this magnitude. The results of this study compels to caution authors to obtain adequate sample sizes and hope that this meta-analytic review can aid in the determination of sample size for future studies.
-
Randomized Controlled Trial Clinical Trial
Double-blind evaluation of short-term analgesic efficacy of orally administered diclofenac, diclofenac plus codeine, and diclofenac plus imipramine in chronic cancer pain.
A prospective double-blind randomized trial was conducted on 184 cancer patients with moderate to severe chronic pain to evaluate the analgesic efficacy and tolerability of diclofenac alone (50 mg q.i.d.) or in combination with a weak opioid (codeine 40 mg q.i.d.), or with an anti-depressant (imipramine, 10 or 25 mg t.i.d.). All demographic and clinical characteristics including cancer type, presence of bone metastases, baseline pain severity, neuropathic and nociceptive pain, and depressive state, were well balanced between the three treatment groups. ⋯ Patients on imipramine plus diclofenac and on placebo plus diclofenac were withdrawn mainly for inadequate efficacy, while patients on codeine plus diclofenac discontinued equally for inadequate efficacy or adverse events. In conclusion, in a short-term evaluation the addition of a tricyclic anti-depressant or a weak opioid to diclofenac did not provide further analgesia with respect to diclofenac administration alone.
-
Randomized Controlled Trial Clinical Trial
Randomized controlled trial of a community-based psychoeducation program for the self-management of chronic pain.
Although chronic pain is a frequent cause of suffering and disability and is costly to society, there continues to be limited access to specialty pain clinic services. Hence, there is a need for cost-effective, accessible interventions that will help people find ways to better manage this difficult problem. This randomized controlled trial examined the effect of a low-cost, community-based, nurse-delivered, group psychoeducation program entitled the Chronic Pain Self-Management Program (CPSMP). ⋯ Results of intention-to-treat analysis indicated that the treatment group made significant short-term improvements in pain, dependency, vitality, aspects of role functioning, life satisfaction and in self-efficacy and resourcefulness as compared to the wait-list control group. Because it has a standard protocol, this intervention has the potential to be reliably delivered at low cost in varied urban and rural community settings and hence be more widely accessible to a greater number of people suffering from chronic pain than is currently the case with more specialized pain clinic services. Based on the results of this study, further research evaluating the long-term impact and potential cost savings to the individual and to the health care system is warranted.