Acute Postoperative Pain

Chronic post-surgical pain (CPSP) represents a major clinical problem associated with impaired functional recovery, reduced quality of life, prolonged opioid use, and increased healthcare utilization. The mechanisms underlying pain chronification are multifactorial and involve complex interactions among surgical trauma, inflammatory responses, central sensitization, neuroimmune activation, and psychosocial risk factors. The CROPS study (Chronification of Post-Surgical Pain and Risk Assessment) is a prospective multicenter randomized controlled trial designed to evaluate the impact of perioperative analgesic strategies on the development of chronic post-surgical pain and to validate a novel questionnaire-based pain chronification risk assessment tool in adult patients undergoing cardiac surgery. Participants will be randomized to receive either standard multimodal opioid-based perioperative analgesia or regional anesthesia-based perioperative analgesia incorporating chest wall plane block techniques, including erector spinae plane block, paravertebral block, or PECS block, according to institutional practice. The study will compare postoperative pain intensity, opioid consumption, postoperative recovery, postoperative complications, health-related quality of life, and the incidence of chronic post-surgical pain at 3 months after surgery. In parallel, the predictive performance of the pain chronification risk assessment questionnaire will be evaluated using discrimination and calibration analyses. The study is conducted as an investigator-initiated academic collaboration between the East Slovakia Institute of Cardiovascular Diseases, Košice, Slovakia, and Uppsala University Hospital, Uppsala, Sweden.

This prospective, randomized, triple-blind, placebo-controlled clinical trial will investigate the effectiveness of the intertransverse process block (ITPB) for postoperative analgesia in patients undergoing elective thoracotomy with unilateral lobectomy. The study will be conducted at a single tertiary center in accordance with the principles of the Declaration of Helsinki, and written informed consent will be obtained from all participants. Patients will be randomized in a 1:1 ratio to receive either ultrasound-guided ITPB with 0.5% bupivacaine or placebo (normal saline) prepared in identical syringes to ensure allocation concealment. The block will be performed by an experienced anesthesiologist immediately after surgery and before emergence from anesthesia. Both groups will receive standardized general anesthesia, multimodal perioperative analgesia, and postoperative intravenous morphine patient-controlled analgesia (PCA). The trial aims to evaluate the analgesic efficacy and opioid-sparing effect of ITPB while maintaining safety and adherence to routine clinical practice. Outcomes will include postoperative pain scores, opioid consumption, rescue analgesia requirement, and adverse events.

This randomized, double-blind clinical trial aims to compare the effectiveness of the Deep Iliacus Plane Block (DIPB) and the Suprainguinal Fascia Iliaca Block (SIFIB) for postoperative pain control in patients undergoing primary total hip arthroplasty. Effective analgesia after hip surgery is essential for early mobilization, reduction of complications, and improved recovery outcomes. Seventy patients scheduled for elective hip arthroplasty under spinal anesthesia will be randomly assigned to receive either DIPB or SIFIB at the end of surgery. Postoperative pain scores, opioid consumption, motor block, and block-related complications will be evaluated over a 48-hour period. The study aims to determine whether DIPB provides superior or comparable analgesia with reduced motor blockade compared to SIFIB, thereby contributing to safer and more comprehensive postoperative pain management in hip surgery patients.

The goal of this clinical trial is to learn whether intravenous buprenorphine administered via a patient-controlled analgesia (PCA) system provides effective and safer postoperative pain control than intravenous oxycodone PCA in adults undergoing video-assisted thoracoscopic surgery (VATS). It will also evaluate the overall tolerability of buprenorphine in the early postoperative period and explore longer-term pain outcomes. The main questions it aims to answer are: Does buprenorphine PCA provide pain control that meets predefined targets during the first 48 hours after VATS (both at rest and during respiratory rehabilitation/mobilization), compared with oxycodone PCA? Does buprenorphine PCA reduce clinically relevant respiratory safety events (e.g., apnea or oxygen desaturation requiring intervention) and excessive sedation, compared with oxycodone PCA? What opioid-related adverse effects (e.g., nausea/vomiting, pruritus, constipation, hypotension) occur with buprenorphine PCA versus oxycodone PCA? Does buprenorphine PCA affect time to first patient-initiated analgesic demand and total opioid consumption within 48 hours? Does the choice of PCA opioid influence quality of recovery and the incidence of persistent postoperative pain at follow-up? Researchers will compare buprenorphine PCA to oxycodone PCA (both as part of standardized multimodal analgesia and perioperative care, including serratus anterior plane block) to determine whether buprenorphine provides non-inferior analgesia with a superior safety profile. Participants will: Be randomly assigned (double-blind) to receive buprenorphine PCA or oxycodone PCA for 48 hours after surgery, alongside standard multimodal analgesia Receive standardized general anesthesia for VATS with one-lung ventilation and an ultrasound-guided serratus anterior plane block at the end of surgery Have pain scores (NRS) recorded at multiple time points over 48 hours, at rest and during rehabilitation, and complete recovery questionnaires (QoR-15) early after surgery Be monitored regularly for vital signs, sedation level (RASS), respiratory events, and other adverse effects, with total opioid use recorded Provide satisfaction ratings at discharge and be followed after discharge to assess persistent postoperative pain/hyperalgesia at 1, 3, and 6 months

Non-steroidal anti-inflammatory drugs (NSAID) are part the multimodal strategy in pain management after surgery. However, major concerns are raised in cardiac surgery given the potential side effects of NSAID with more bleeding and acute kidney injury. The investigators hypothesized that NSAID are safe in the early postoperative course after cardiac surgery with respect to contraindication.

This is a single-center pilot study to determine if an adductor canal continuous nerve block is superior to single injection nerve block following total knee arthroplasty. Investigators will randomize participants to either continuous nerve block or single injection nerve block for the adductor canal preoperatively. They will assess differences in pain (measured in numeric rating scale), opioid consumption, and physical therapy milestones from postoperative day 0 to 7.

The goal of this clinical trial is to evaluate the efficacy of intertransverse process block (ITPB) in blunting sympathetic response of sternotomy, achieving perioperative opioid-sparing and improving quality of recovery in adult patients undergoing elective cardiac surgery (e.g., coronary artery bypass graft \[CABG\], valve repair/replacement, or combined CABG/valve procedures). The main questions it aims to answer are: 1. To investigate the efficacy of intertransverse process block (ITPB) on quality of recovery after cardiac surgery 2. To investigate the efficacy of ITPB on the sympathetic response on incision, intraoperative and postoperative morphine requirement 3. To investigate the efficacy of ITPB on surgical outcomes including time to weaning off mechanical ventilation, length of ICU/ hospital stay and incidence of neuropathic pain after surgery Researchers will compare patients receiving bilateral ITPB with levobupivacaine to those receiving sham blocks to determine if ITPB reduces CPSP, improves pain control, and decreases opioid consumption.

This study aims to externally validate two clinical prediction models for moderate-to-severe acute post-surgical pain and chronic post-surgical pain. This multi-centre, prospective cohort study will be conducted in Denmark and will include adult patients undergoing various types of elective or sub-acute surgical procedures.

This study seeks to evaluate the efficacy of transcranial direct current stimulation (tDCS) and Afferent Vagus nerve simulation (VNS) in treating acute postoperative pain of patients in the post-anesthesia care unit after general surgery. Study outcomes will include changes in pain levels and vital signs. For patients who are admitted after surgery, opioid consumption in the 24 hours after surgery and time from surgery to discharge are recorded as secondary outcomes. Patients will be divided in the following comparison groups: * Group +/+ will receive ten minutes of active tDCS followed by ten minutes of active VNS. * Group +/- will receive ten minutes of active tDCS followed by ten minutes of sham VNS. * Group -/+ will receive ten minutes of sham tDCS followed by ten minutes of active VNS. * Group -/- will receive ten minutes of sham tDCS followed by ten minutes of sham VNS.

The goal of this clinical trial is to measure the median effective dose of oxycodone for the treatment of acute pain after thoracoscopic lobectomy. This clinical trial was divided into two groups based on age, Group I (Age \< 65 years old) and Group II (Age ≥65 years old). We used the sequential allocation designed by Dixon. The initial oxycodone dose was set to 0.1 mg/kg.A satisfactory or an unsatisfactory analgesic response of the previous patient determined, respectively, the relative 10% decrease or increase in the dose of oxycodone the next patient received in the same group. The patient before the first crossover point was included as the first case for ED50 estimation in each group.The study was conducted until 7 crossover points were collected

Cryoneurolysis is a regional anaesthetic technique that works by freezing peripheral sensory nerves. This technique can potentially provide analgesia after total knee arthroplasty (TKA). However, the technique is expensive and comprehensive. Pain 24 hours after surgery is associated with high amounts of late acute pain. Therefore, the aim of the current study was to compare the effect of postoperative cryoanalgesia with a sham treatment on acute postoperative pain in TKA patients with moderate to severe pain on the first postoperative day. The cryoanalgesia treatment will be performed 24 hours after surgery. Afterward, the patients will be followed for 24 weeks to determine the level of pain among other outcomes.

To gain a clearer understanding of the association between frailty and postoperative acute pain in elderly thoracoscopic surgery patients and its underlying mechanisms, to provide new solution ideas to reduce the level of postoperative acute pain and improve the debilitating state of elderly thoracoscopic surgery patients, and consequently improve their quality of life and mental status.