View clinical trials related to Hyperalgesia.
Filter by:To evaluate the effect of oral gabapentin premedication on hyperalgesia in elderly patients undergoing staged bilateral cataract operations under monitored anesthesia care
The concept of Enhanced Recovery After Surgery(ERAS) has been prevalent in recent years. In the ERAS guideline, short-acting anesthetics, instead of long-acting opioid anesthetics, were recommended during surgery to decrease post-operative complication and length of hospital stay. Propofol-remifentanil based total intravenous anesthesia (TIVA) can provide quicker emergence and decreased post-operative nausea and vomiting. However, the prescription of opioid (especially remifentanil) may induce opioid-induced hyperalgesia (OIH) and increase the requirement of analgesics. Previous studies provided some strategies to prevent OIH. The purpose of this study is to investigate the effect of adding remifentanil(1 mcg/kg) after emergence and endotracheal extubation in breast cancer females receiving breast surgery under propofol-remifentanil based TIVA for the prevention of OIH.
Nocebo effects are adverse effects induced by patients' expectations. Nocebo effects on pain may underlie several clinical conditions, such as chronic pain. These effects can be learned via classical conditioning mechanisms. In the lab, nocebo effects are commonly studied via conditioning with continuous reinforcement (CRF) during which 100 percent of unconditioned pain stimuli are paired to conditioned stimuli (i.e., the activation of a mock medical device). Partial reinforcement (PRF) provides a more uncertain pairing during conditioning, where less than 100 percent of unconditioned pain stimuli are paired to conditioned stimuli. This method provides a potentially more clinically relevant learning platform to study how nocebo effects on pain are induced. In this study, the efficacy of conditioning with PRF, CRF, and sham-conditioning in inducing nocebo effects on pain will be compared. Furthermore, a counterconditioning method will be compared to an extinction method for the attenuation of nocebo effects on pain. Given the relevance of nocebo effects for patients, it is important to ascertain effective & clinically relevant methods to understand how nocebo effects may be formed and attenuated. This study is conducted by Leiden University.
The majority of migraineurs seeking secondary or tertiary medical care develop cutaneous allodynia during the course of migraine, a sensory abnormality mediated by sensitization of central trigeminovascular neurons in the spinal trigeminal nucleus. Triptan therapy can render allodynic migraineurs pain-free within a narrow window of time (20-120 min) that opens with the onset of pain and closes with the establishment of central sensitization. This calls for the development of drugs that can tackle ongoing central sensitization and render allodynic migraineurs pain-free after the window for triptan therapy has expired. There are two main objectives the investigators seek to achieve from this study: to determine whether oral administration of DFN-15 (solution of a COX2 inhibitor, Celecoxib) terminates migraine attacks when given to allodynic participants 3 hours after attack onset; and to determine whether mechanical and heat allodynia that develop during acute migraine attacks could be reversed by late (> 3hrs after attack onset) treatment with DFN-15. Participants will be recruited from the Headache Center and randomized in a double-blinded fashion to receive either the active drug (DFN-15) or placebo in a ratio of 4:1.The participants will be instructed to return to the clinic during a migraine. At the 'during-migraine' visit, which will begin 3 hours after onset of headache, the investigators will document headache intensity, associated symptoms, and mechanical and heat pain threshold (first) before treatment (at 180 min after onset of headache) and (second) at a 120 min after treatment (5 hours after headache onset). Based on our prior experience studying migraine patients, the investigators plan to screen 100 patients to achieve 50 participants completing the 2 study visits as planned. The active drug group will consist of 80/100 patients and 20/100 patients will receive the placebo. The study will be terminated as soon as the first 40 participants who received the DFN-15 and first 10 patients who received placebo completed visit 2.
The purpose of this study is to investigate pain evoked responses and facilitation of NGF-induced mechanical muscle hyperalgesia over time following an acute exercised-induced ischemic condition in a NGF-sensitized muscle.
Randomized, double-blinded, three arm study in adult patients undergoing first time coronary artery bypass grafting (CABG) surgery with median sternotomy. The investigators will examine the effects of three fentanyl dosing schemes (high-dose bolus, low-dose bolus, continuous dose) on the area of hyperalgesia and allodynia at 24 and 48h as well as on persisting pain at 3, 6, and 12 months. Additionally, the investigators will measure fentanyl concentrations throughout anesthesia.
The purpose of this study is to investigate the sensory-motor cortical excitability response to delayed onset muscle soreness (DOMS) on Extensor Carpi Radialis (ECR) muscle during muscle hyperalgesia provoked by nerve growth factor (NGF).
American Society of Anaesthesiologist physical status (ASA) I-III 105 patients who undergoing major abdominal surgery in obstetric and gynaecology clinic were recruited to this study. Patients were randomized into the 3 groups. Lumbar epidural catheter will be inserted to the all patients. After than anaesthesia induction will provide with 2 mg/kg propofol and 0.6 mg/kg rocuronium. Desflurane and azot protoxit (N2O)-O2 will use for anaesthesia maintenance. During surgical operation, 0.3 microgram/kg/h remifentanil infusion will continuous till the end of surgery. In group I, 2 ml serum physiologic (0.9 NaCL)will apply from epidural catheter before surgical incision. In group II, 1 mg morphine will apply from epidural catheter before surgical incision. In group III, 1 mg morphine will apply from epidural catheter at the time point of peritoneum is closed. Epidural patient controlled analgesia will provide with bupivacaine for postoperative analgesia. Postoperative pain will be assessed with numerical pain scale. Postoperative analgesic requirement will be calculated. Hyperalgesia will detect with algometer and von Frey ligaments.
The purpose of this study is to investigate and determine the time course and distribution on muscle hyperalgesia and muscle pain in a repeated, low dose NGF model. It is hypothesized that low dosages i.m injections of NGF are able to induce mechanical hyperalgesia and muscle soreness in a same manner (effect of duration) as for dosages previously used in NGF studies. Furthermore, it is also speculated if several injections of low dose NGF into the muscle combined are able to course immediate pain sensation and spreading of muscle hypersensitivity.
The purpose of this study is to evaluate the correlation between β-endorphin levels in blood plasma and saliva in healthy participants with different pain sensitivity and in those with acute pain in oral and maxillofacial region. Expected results - Relation between blood plasma and saliva β-endorphins levels - Differences of blood plasma β-endorphins levels in healthy participants with different pain sensitivity and in those with acute pain - Differences of saliva β-endorphins levels in healthy participants with different pain sensitivity and in those with acute pain - Objective method of patient's pain sensation evaluation - Correlation between patient's self-reported understanding of pain levels in oral surgery procedures, levels in saliva and blood plasma β-endorphins levels and sensitivity to cold test results Study protocol: Selection of participants 1. Evaluation of pain perception in oral surgery procedures by healthy adult participants. 2. Groups formation, according to the results from first stage, resulting in high and low pain rating participants groups. 3. Control group formation from patients with acute pain in oral and maxillofacial region Control rating of participants 1. Patients that have been assigned to groups according to subjective pain ratings in oral surgery procedures will have to repeat the same questionnaire to ensure the correct group assignment. 2. Patients that have been assigned to groups according to subjective pain ratings in oral surgery procedures, will undergo the sensitivity and tolerance to cold pain test. 3. Patients that were assigned to control-acute pain group, will be included in further study stages only with clinically diagnosed cause of acute pain in oral and maxillofacial region to avoid possible psychogenic or general diseases pain. Evaluation of β-endorphins - sampling 1. Saliva samples will be collected by all further included participants by one selves participants with researchers supervision. 2. Blood samples will be collected from forearm veins by researcher. Evaluation of β-endorphins - laboratorial examination 1. Levels of β-endorphins in saliva and blood will be evaluated according to manufacturer of β-endorphins evaluation kit for human research. Every sample will be evaluated twice and the mean level will be evaluated. Statistical analysis 1. Statistical analysis will be produced to access all possible relationships