Effects of an Opioid Free/Sparing Care Pathway for Patients Undergoing Obesity Surgery

Overview

The opioid consumption has exploded in the western world, and for some patient populations such as obese patients, patients with sleep apnoea or patients undergoing cancer treatment, opioid-sparing/ opioid-free strategies could have positive effects on outcomes. Studies suggest that opioids could have opioid-induced immunosuppression, induce chronic post-operative pain syndrome and hyperalgesia in addition to the more well-known side effects such as respiratory depression, nausea, bladder, and bowel dysfunction. Hence, new studies are needed on the impact of person-centered care programs that combine pharmaceutical and non-pharmaceutical strategies to reduce the adverse short and long-term effects of opioid therapy. The overall aim is to evaluate the short-, medium- and long-term effects of opioid-free care pathways with or without person-centred care compared to conventional opioid-based treatment in patients undergoing obesity surgery. Specific aims 1. Determine the effects of opioid-free care with or without person-centred care compared with conventional opioid-based general anaesthesia on the cognitive and physical quality of recovery after surgery up to 24 months after surgery (short-term: postoperative to discharge, medium-term: 14 days, 3 months, long-term: 6 months, 12 months and 24 months). 2. Describe the clinical monitoring trend regarding nociceptive response intraoperatively between opioid-free and conventional care. 3. Map the impact of opioid-free anaesthesia (with and without person-centred care) on the usage of opioids up to 24 months after hospital discharge. 4. Explore the patients' experience of quality of life, economic evaluations, self-efficacy and recovery after surgery in opioid-free care with or without person-centred care during the first year post-surgery. The aims will be evaluated by a prospective, randomized, non-blinded, non-commercial multi-centre study (Nov 2018-Dec 2022) approved by the Swedish Medicines Agency (EU-CT 2023-505934-86-00) and the ethical review board (DNR 1006-17).

Aim To evaluate the effects of opioid sparing care pathways compared to conventional opioid-based treatment for pain relief, opioid consumption, recovery after surgery, self-efficacy and health economy in patients undergoing obesity surgery. The aim will be investigated by a prospective, randomized, non-blinded, non-commercial multi-centre study(Nov 2018-Dec 2022), approved by the Swedish Medicines Agency (EU-CT 2023-505934-86-00) and the ethical review board (DNR 1006-17). Hypothesis 1. An opioid-free care pathway provides non-inferior pain relief as the conventional care with opioids during the post-operative phase. Primary endpoints: Determine the quality of recovery after surgery 1\. No difference in pain (NRS pain (0-10)) between opioid-free intervention with or without (Phase 1 \& 2) person-centred care and conventional treatment (control group) during the postoperative phase until discharge to the surgical ward. Secondary endpoints: An opioid-sparing treatment provides improved combined outcomes (composite score) consisting of 1) Self-Efficacy, 2) Postoperative Quality of Recovery Scale (PQRS), hospital readmission, or death at 3 months compared to conventional treatment. An opioid-sparing treatment results in reduced opioid consumption during the peri- and postoperative period until discharge to the ward compared to conventional treatment. An opioid-sparing treatment results in reduced opioid consumption throughout the hospital stay compared to conventional treatment. An opioid-sparing treatment results in decreased pain experience according to the Numeric Rating Scale (NRS) at 3 months and 6 months compared to conventional treatment. An opioid-sparing treatment leads to earlier recovery after surgery measured with PQRS compared to conventional treatment postoperatively (20 minutes, 40 minutes), during hospitalization (24-72 hours), and thereafter (14 days, 30 days, 3 months, 6 months, 12 months, and 24 months). An opioid-sparing treatment increases confidence in coping with unexpected events measured with the General Self-Efficacy Scale compared to conventional treatment after the in-hospital period (3 months, 6 months, 12 months, 24 months). An opioid-sparing treatment improves quality of life measured with RAND-36 and EQ5D compared to conventional treatment after the in-hospital period (3 months, 6 months, 12 months, 24 months) An opioid-sparing treatment results in equivalent length of hospital stay compared to conventional treatment during the in-hospital period. Mapping of long-term prescription of analgesic drugs. Does an opioid-sparing treatment impact the long-term use of analgesic medications. Explorative endpoints: Describe the intraoperative nociception level between opioid-free anaesthesia and conventional anaesthesia using the Medasense PMD-200 (NOL) monitor. Economic evaluation: Performing cost-utility analysis/ cost-effectiveness analyses. Power Pain: To determine noninferiority with a power of 0.8 (i.e., the probability of \> 0.8 for the lower limit of a two-sided 95% confidence interval (using Fisher's nonparametric permutation test)), the difference of change in pain using the NRS from arrival to the recovery unit after surgery to discharge from the recovery unit will be used. Forty-three patients are required in each group and phase, with an SD for the change in the NRS estimated to be 1.62 from a small pilot study (noninferiority margin -1.0). The estimated change was assumed to be equal in the groups. To compensate for a potential interruption in the study or dropouts, we chose to include 55 patients in Intervention Phase 1, 55 patients in Intervention Phase 2 and a total of 110 patients in the control group (to follow intervention Phases 1 and 2, each 55 patients). Recovery after surgery: To detect an overall difference in the quality of recovery between groups over the entire study length, with a power of 0.8 and P \< 0.05 and taking into consideration a dropout of over 30% as seen in other studies using the PQRS, we need to include at least 30 patients in each group 26. The control group will receive usual care and treatment according to the hospital's routines, where pain relief is obtained with opioids postoperatively. Pharmacological treatment in the intervention group differs solely from the patients in the usual group by replacing opioids with the following nonopioid perioperative treatment: dexmedetomidine, esketamine, lidocaine and TENS (for exact dosing, please visit EU-CT 2023-505934-86-00). Postoperative patient-controlled pain treatment with high-intensity/high-frequency TENS is used if the patient perceives pain over NRS ≧ 3 postoperatively and during remaining hospitalisation. Intervention Phase 1 tests the pharmacological and non-pharmacological interventions (TENS) compared to the control group that receives standard care with opioids intra- and postoperatively. Phase 2 intervention that follows after completion of Phase 1 intervention tests the pharmacological and nonpharmacological interventions compared to conventional treatment, supplemented by an evidenced-based PCC approach throughout the continuum of postoperative care. The two phases will primarily be analysed separately (i.e., between the control group and intervention Phase 1 and between the control group and intervention Phase 2).