View clinical trials related to Postoperative Hyperalgesia.
Filter by:To explore the effect of daytime variation on postoperative hyperalgesia induced by opioids. Patients receiving endoscopy surgery under general anesthesia during 08:00-12:00(morning group, n=30) and 14:00-18:00(afternoon group, n=30) using remifentanil for anesthesia maintenance were respectively included. Postoperative hyperalgesia at PACU and 24 hours after surgery were assessed through mechanical pain measurement. Comparative analysis of postoperative hyperalgesia levels, pain and analgesic requirements between morning group and afternoon group were performed.
Postoperative hyperalgesia (POH) is a paradoxical clinical state of increased sensation of pain or increased sensitivity to non-painful stimuli at the site of surgery or at a surrounding area that was not directly injured. Opioid-induced hyperalgesia (OIH) and nociceptive-induced hyperalgesia (NIH) are the two main causes of POH.N-methyl-D-aspartate receptor (NMDAR) activation plays a central role in the development of POH.S-ketamine，which is a NMDA-receptor antagonist,has been on the market in china since 2019.The aim of this study is to evaluate the effects of S-ketamine on POH and chronic postoperative pain after video-assisted thoracic surgery.
Postthoracotomy acute pain is followed by persistent postsurgical pain in 20-30% of the patients, defined as pain that lasts more than 3-6 months after surgery. Acute pain and hyperalgesia around the surgical wound are some of the risk factors associated to the development of chronic pain. Ketamine, as a NMDA antagonist mainly at spinal level, might reduce periincisional hyperalgesia and persistent postsurgical pain after thoracotomy. Therefore, the investigators hypothesized that continuous ketamine infusion at subanesthetic dose would potentiate epidural ropivacaine and fentanyl-induced analgesia after thoracotomy, reduce periincisional hyperalgesia and long-term postoperative pain. To test these hypothesis, the investigators administered a low dose of intravenous ketamine or epidural ketamine or placebo to patients who received an epidural infusion of ropivacaine and fentanyl for postthoracotomy pain.
We propose performing a study in which we compare the effects of bupivacaine and fentanyl with a different drug combination − bupivacaine and clonidine. The principal research questions of the study are: 1. To compare the effect of clonidine (with bupivacaine), injected into the epidural space on the extent of hyperalgesia (abnormal pain/sensitivity in the uninjured skin surrounding the operation site) in patients undergoing operations for bowel disease, with that of fentanyl (with bupivacaine). 2. To compare the effect of clonidine (with bupivacaine), injected into the epidural space on the incidence of chronic pain 6 months after surgery for bowel disease, with that of fentanyl (with bupivacaine).