Trajectories of pain and opioid use up to one year after surgery: analysis of a European registry.

BACKGROUND: Long-term opioid use after surgery is a crucial healthcare problem in North America. Data from European hospitals are scarce and differentiation of chronic pain has rarely been considered. METHODS: In a mixed surgical cohort of the PAIN OUT registry, opioid use and chronic pain were evaluated before surgery, and 6 and 12 months after surgery (M6/M12). Subgroups with or without opioid medication and pre-existing chronic pain were analysed. M12-chronic pain was categorised as chronic postsurgical pain (CPSP) meeting the ICD-11 definition, chronic pain related to surgery not meeting the ICD-11 definition, and chronic pain unrelated to surgery. Primary endpoint was the rate of M12 opioid users. Variables associated with M12 opioid use and patient-reported outcomes were evaluated. RESULTS: Of 2326 patients, 5.5% were preoperative opioid users; 4.4% and 3.5% took opioids at M6 and M12 (P<0.001). Chronic pain before operation and at M6/M12 was reported by 41.2%, 41.8%, and 34.7% of patients, respectively (P<0.001). The rate of M12 opioid users was highest in group unrelated (22.3%; related 8.3%, CPSP 1.5%; P<0.001). New opioid users were 1.1% (unrelated 7.1%, related 2.3%, CPSP 0.7%; P<0.001). M12 opioid users reported more pain, pain-related physical and affective interference, and needed more opioids than non-users. The predominant variable associated with M12 opioids was preoperative opioid use (estimated odds ratio [95% confidence interval]: 28.3 [14.1-56.7], P<0.001). CONCLUSIONS: Opioid use was low in patients with CPSP, and more problematic in patients with chronic pain unrelated to surgery. A detailed assessment of chronic pain unrelated or related to surgery or CPSP is necessary. CLINICAL TRIAL REGISTRATION: NCT02083835.

Effects of adding low-dose esketamine to sufentanil and propofol sedation during cervical conization: a single-centre, randomized controlled trial.

BACKGROUND: Cervical conization is a brief but painful procedure that can be performed under sufficient sedation with propofol and opioids. However, this sedation approach comes with a high risk of sedation-related adverse events (SRAEs). Esketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, causes less cardiorespiratory depression than opioids. The aim of this study was to assess the efficacy and safety of adding a low dose of esketamine to propofol and sufentanil sedation as an opioid-reduced regimen. METHODS: A total of 122 consecutive patients with ASA I-II, body mass index < 30, and STOP-BANG score < 3 who underwent cervical conization were enrolled and randomly divided into Group S and Group ES. Using a closed-loop target-controlled infusion (TCI) pump with a target bispectral index (BIS) value of 60 ± 5, patients in Group S were sedated with 0.2 mcg·kg-1 sufentanil and propofol, while patients in Group ES were sedated with 0.15 mg·kg-1 esketamine, 0.1 mcg·kg-1 sufentanil and propofol. The primary outcome was the incidence and severity of SRAEs, while the secondary outcomes included effectiveness of sedation, awakening time, psychotomimetic side effects, postoperative pain, postoperative nausea and vomiting, and patient and gynaecologist satisfaction. RESULTS: Data from 120 patients were analysed. The incidence of composite SRAEs was significantly higher in Group S than in Group ES (85.0% vs. 56.7%, P < 0.05). Furthermore, the severity of SRAEs was higher in Group S than in Group ES (P < 0.001). There were no significant differences in the effectiveness of sedation, awakening time, psychotomimetic side effects, postoperative pain, postoperative nausea and vomiting, or patient and gynaecologist satisfaction between the two groups. CONCLUSION: Adding low-dose esketamine to propofol and sufentanil sedation reduces the incidence and severity of SRAEs in patients undergoing cervical conization, with equal sedation efficacy, recovery quality, and no additional psychomimetic side effects. TRIAL REGISTRATION: ChiCTR2000040457 , 28/11/2020.

Effect of two different doses of nalbuphine for postoperative analgesia in children with cleft palate: a randomized controlled trial.

BACKGROUND: Cleft palate repair surgery may result in severe pain in the immediate postoperative period. The aim of this study is to compare the effects of different doses of nalbuphine for postoperative analgesia in children with cleft palate. METHODS: From November 2019 to June 2021, 90 children (45 males and 45 females, age 9-20 months old, ASA class I-II) were selected for palatoplasty. They were randomly divided into three groups: the control group (Group C), the N1 group (postoperative analgesia with 0.05 mg/kg/h nalbuphine) and the N2 group (postoperative analgesia with 0.075 mg/kg/h nalbuphine). Each group had 30 cases. Nalbuphine was not continuously infused in Group C but was continuously infused in Groups N1 and N2 at rates of 0.05 mg/kg/h and 0.075 mg/kg/h, respectively, for 24 h for postoperative analgesia. The FLACC analgesia score and Ramsay Sedation score were recorded at 10 min (T1), 30 min (T2), 2 h (T3), 12 h (T4) and 24 h (T5) after the operation. Adverse reactions such as nausea, vomiting and respiratory depression were observed and recorded. RESULTS: Compared with those in Group C, the FLACC scores in the N1 and N2 groups decreased significantly at T1-T5 (p < 0.05); the Ramsay Sedation score in the N1 group was significantly higher at T3 and T4 (p < 0.05), and that in the N2 group was significantly higher at T1-T5 (p < 0.05). Compared with that in the N1 group, the FLACC score in the N2 group was not significantly different, and the Ramsay Sedation score increased significantly at T5 (p < 0.05). CONCLUSION: Using 0.05 mg/kg/h Nalbuphine continuously for 24 h for postoperative analgesia in children with cleft palate has a better effect and fewer adverse reactions. TRIAL REGISTRATION: This study was registered at ChiCTR1900027385 (11/11/2019).

Effect of esketamine on postoperative analgesia and postoperative delirium in elderly patients undergoing gastrointestinal surgery.

OBJECTIVE: To investigate the analgesic effect of esketamine combined with low-dose sufentanil in elderly patients after gastrointestinal surgery, and whether the anti-inflammatory effect of esketamine is involved in the mechanism of postoperative delirium. METHOD: We enrolled sixty elderly patients (age ≥ 65 years old, American Society of Anesthesiologists (ASA) grade I-III) who underwent gastrointestinal surgery. Patients were randomly assigned to Group C (control group) who received sufentanil 2 ug/kg, and Group E (experimental group) who received sufentanil 1.5 ug/kg + esketamine 1 mg/kg, with 30 patients in each group. All patients underwent total intravenous anesthesia during the surgery and were connected to a patient-controlled intravenous analgesia (PCIA) pump after surgery. The primary outcome was the evaluation of pain at 4, 24, 48 h after surgery which was evaluated by NRS scores. In secondary outcomes, inflammation was assessed by measuring IL-6 levels using ELISA. The postoperative delirium and the occurrence of adverse reactions were observed on the 1st and 3rd day after surgery. RESULTS: The NRS scores at 4, 24, and 48 h after surgery in the experimental group [(4.53 ± 1.22), (3.46 ± 0.73), (1.37 ± 0.99)] were lower than that in the control group [(5.23 ± 1.16), (4.46 ± 0.77), (2.13 ± 0.78)] (P < 0.05). The concentration of serum IL-6 in the experimental group at 24 and 48 h after operation [(15.96 ± 4.65), (11.8 ± 3.24)] were lower than that in the control group [(23.07 ± 4.86), (15.41 ± 4.01)] (P < 0.05); the incidence of postoperative delirium in the experimental group was less than that in the control group (P < 0.05); there was no significant difference in the incidence of postoperative nausea and vomiting between the two groups (P > 0.05), and neither group had nightmares or delirium. CONCLUSION: Esketamine may enhance postoperative pain management compare with sufentanil, and esketamine has anti-inflammatory effects that reduce the incidence of postoperative delirium. TRIAL REGISTRATION: Full name of the registry: Chinese Clinical Trial Registry. TRIAL REGISTRATION NUMBER: ChiCTR2300072374. Date of registration:2023/06/12.

Postoperative pain after different doses of remifentanil infusion during anaesthesia: a meta-analysis.

BACKGROUND: This meta-analysis aimed to explore the correlation between the different doses of remifentanil-based anaesthesia and postoperative pain in randomised trials. METHODS: The electronic databases including PubMed, Cochrane, clinical trial registries, and Google Scholar were searched up to November 2022 for randomised controlled trials (RCTs) that assessed the dose dependent efficacy of remifentanil for postoperative pain intensity and hyperalgesia. RESULTS: 31 studies involving 2019 patients were included for analysis. Compared with the high remifentanil dose administration, patients in low doses showed less postoperative pain intensity at 1-2 h (weighted mean differences (WMD): 0.60, 95% CI, 0.05 to 1.15), 3-8 h (WMD: 0.38, 95% CI, 0.00 to 0.75), 24 h (WMD: 0.26, 95% CI, 0.04 to 0.48) and 48 h (WMD: 0.32, 95% CI, 0.09 to 0.55). Remifentanil-free regimen failed to decrease the pain score at 24 h (WMD: 0.10, 95% CI, -0.10 to 0.30) and 48 h (WMD: 0.15, 95% CI, -0.22 to 0.52) in comparison with remifentanil-based anaesthesia. After excluding trials with high heterogeneity, the dose of the remifentanil regimen was closely correlated with the postoperative pain score (P=0.03). In addition, the dose of the remifentanil regimen was not associated with the incidence of postoperative nausea and vomiting (PONV) (P=0.37). CONCLUSIONS: Our meta-analysis reveals that the low dose of remifentanil infusion is recommendable for general anaesthesia maintenance. No evidence suggests that remifentanil-free regimen has superiority in reducing postoperative pain. Moreover, remifentanil doesn't have a dose dependent effect in initiating PONV. TRIAL REGISTRATION: The protocol of present study was registered with PROSPERO (CRD42022378360).

The median effective concentration of ropivacaine for ultrasound-guided caudal block in children: a dose-finding study.

PURPOSE: To determine the 50% minimum effective concentration (MEC50) and the 95% effective concentration (MEC95) of ropivacaine for ultrasound-guided caudal block during hypospadias repair surgery of pediatric patients. METHODS: Children were enrolled with the American Society of Anesthesiologists (ASA) physical status I-II undergoing elective hypospadias repair surgery. Children were grouped into two age groups: toddlerhood (1-3 years old) and preschool (3-6 years old). We measured The MEC50 using Dixon's up-and-down method. The first children received the caudal block with 1.0 mL/kg of 0.15% ropivacaine. We determined each subsequent patient's concentration based on the previous patient's response and adjusted the concentration in intervals of 0.015%. Meanwhile, the probit regression analysis obtains 95% effective concentration (MEC95). In addition, we recorded the general condition, adverse events, and postoperative pain of each child. RESULTS: 46 children undergoing elective hypospadias repair surgery were included in this study, 22 in the toddlerhood group and 24 in the preschool group. Of the total number of patients, the caudal block was successful in 25 (54%) and failed in 21 (46%). The MEC50 of 1 ml/kg ropivacaine was 0.102% (95% CI 0.099%, 0.138%) in the toddlerhood group and 0.129% (95% CI 0.124%, 0.138%) in the preschool group. The MEC95 of 1 ml/kg ropivacaine was 0.148% (95% CI 0.131%, 0.149%) in the toddlerhood group and 0.162% (95% CI 0.134%, 0.164%) in the preschool group. Our results showed that ropivacaine concentration was statistically different between preschool children and toddlers (P < 0.001). None of the adverse events occurred. CONCLUSIONS: This study showed that children in the preschool group required higher concentrations of ropivacaine than children in the toddler group during ultrasound-guided sacral block combined with non-intubated general anesthesia. At the same time, this method of anesthesia is safe and effective for children undergoing surgery for hypospadias.

Nonopioid Analgesic Prescriptions Filled after Surgery among Older Adults in Ontario, Canada: A Population-based Cohort Study.

BACKGROUND: The objective was to assess changes over time in prescriptions filled for nonopioid analgesics for older postoperative patients in the immediate postdischarge period. The authors hypothesized that the number of patients who filled a nonopioid analgesic prescription increased during the study period. METHODS: The authors performed a population-based cohort study using linked health administrative data of 278,366 admissions aged 66 yr or older undergoing surgery between fiscal year 2013 and 2019 in Ontario, Canada. The primary outcome was the percentage of patients with new filled prescriptions for nonopioid analgesics within 7 days of discharge, and the secondary outcome was the analgesic class. The authors assessed whether patients filled prescriptions for a nonopioid only, an opioid only, both opioid and nonopioid prescriptions, or a combination opioid/nonopioid. RESULTS: Overall, 22% (n = 60,181) of patients filled no opioid prescription, 2% (n = 5,534) filled a nonopioid only, 21% (n = 59,608) filled an opioid only, and 55% (n = 153,043) filled some combination of opioid and nonopioid. The percentage of patients who filled a nonopioid prescription within 7 days postoperatively increased from 9% (n = 2,119) in 2013 to 28% (n = 13,090) in 2019, with the greatest increase for acetaminophen: 3% (n = 701) to 20% (n = 9,559). The percentage of patients who filled a combination analgesic prescription decreased from 53% (n = 12,939) in 2013 to 28% (n = 13,453) in 2019. However, the percentage who filled both an opioid and nonopioid prescription increased: 4% (n = 938) to 21% (n = 9,880) so that the overall percentage of patients who received both an opioid and a nonopioid remained constant over time 76% (n = 18,642) in 2013 to 75% (n = 35,391) in 2019. CONCLUSIONS: The proportion of postoperative patients who fill prescriptions for nonopioid analgesics has increased. However, rather than a move to use of nonopioids alone for analgesia, this represents a shift away from combination medications toward separate prescriptions for opioids and nonopioids.

Intraoperative Methadone in Next-day Discharge Outpatient Surgery: A Randomized, Double-blinded, Dose-finding Pilot Study.

BACKGROUND: Contemporary perioperative practice seeks to use less intraoperative opioid, diminish postoperative pain and opioid use, and enable less postdischarge opioid prescribing. For inpatient surgery, anesthesia with intraoperative methadone, compared with short-duration opioids, results in less pain, less postoperative opioid use, and greater patient satisfaction. This pilot investigation aimed to determine single-dose intraoperative methadone feasibility for next-day discharge outpatient surgery, determine an optimally analgesic and well-tolerated dose, and explore whether methadone would result in less postoperative opioid use compared with conventional short-duration opioids. METHODS: This double-blind, randomized, dose-escalation feasibility and pilot study in next-day discharge surgery compared intraoperative single-dose IV methadone (0.1 then 0.2, 0.25 and 0.3 mg/kg ideal body weight) versus as-needed short-duration opioid (fentanyl, hydromorphone) controls. Perioperative opioid use, pain, and side effects were assessed before discharge. Patients recorded pain, opioid use, and side effects for 30 days postoperatively using take-home diaries. Primary clinical outcome was in-hospital (intraoperative and postoperative) opioid use. Secondary outcomes were 30-day opioid consumption, pain, opioid side effects, and leftover opioid counts. RESULTS: Median (interquartile range) intraoperative methadone doses were 6 (5 to 7), 11 (10 to 12), 14 (13 to 16), and 18 (15 to 19) mg in 0.1, 0.2, 0.25, and 0.3 mg/kg ideal body weight groups, respectively. Anesthesia with single-dose methadone and propofol or volatile anesthetic was effective. Total in-hospital opioid use (IV milligram morphine equivalents [MME]) was 25 (20 to 37), 20 (13 to 30), 27 (18 to 32), and 25 (20 to 36) mg, respectively, in patients receiving 0.1, 0.2, 0.25 and 0.3 mg/kg methadone, compared to 46 (33 to 59) mg in short-duration opioid controls. Opioid-related side effects were not numerically different. Home pain and opioid use were numerically lower in patients receiving methadone. CONCLUSIONS: The most effective and well-tolerated single intraoperative induction dose of methadone for next-day discharge surgery was 0.25 mg/kg ideal body weight (median, 14 mg). Single-dose intraoperative methadone was analgesic and opioid-sparing in next-day discharge outpatient surgery.

Comparison of two doses of intrathecal morphine in laparoscopic donor hepatectomy: A randomized double-blinded non-inferiority trial.

BACKGROUND: Intrathecal morphine (ITM) injection is an effective postoperative analgesic strategy in open or laparoscopic donor hepatectomy; however, the optimal dose has not been determined. In this trial, we compared the post-operative analgesic effects of two doses (300 vs. 400 µg) of ITM injections. METHODS: In this prospective randomized non-inferiority trial, 56 donors were divided into either the 300 µg or 400 µg ITM group (n = 28, each). The primary outcome was the resting pain score at 24 h postoperatively. Pain scores, cumulative opioid consumption, and side effects (postoperative nausea and vomiting [PONV]) were compared up to 48 h postoperatively. RESULTS: Fifty-five donors participated in the entire study. The mean resting pain scores at 24 h after surgery were 1.7 ± 1.6 and 1.7 ± 1.1 in the ITM 300 and ITM 400 groups, respectively (mean difference, 0 [95% CI, -.8 to .7], p = .978). The upper limit of the 95% CI was lower than the prespecified non-inferiority margin (δ = 1), indicating that non-inferiority had been established. The incidence of PONV was lower in the ITM 300 group than in the ITM 400 group at 18 (p = .035) and 24 h postoperatively (p = .015). There were no significant differences in the resting and coughing pain scores and cumulative opioid consumption at any time point. CONCLUSION: For laparoscopic donor hepatectomy, preoperative ITM 300 µg exhibited non-inferior postoperative analgesic effects compared to ITM 400 µg, with a lower incidence of PONV.

SIRT2 overexpression decreases remifentanil-stimulated post-surgical hyperalgesia via microglia.

Remifentanil (Remi)-induced hyperalgesia is a serious but common postoperative clinical problem. Sirtuin 2 (SIRT2) is essential in the pathogenetic mechanisms of several neurological disorders. However, whether SIRT2 contributes to the modulation of Remi-induced postsurgical hyperalgesia (POH) is unknown. Here, we investigated the regulatory potential of SIRT2 in Remi-stimulated POH. A rat Remi-stimulated POH model was built by infusing Remi in the surgical incision. Mechanical allodynia and thermal hyperalgesia were separately assessed by paw withdrawal mechanical threshold (PWMT) and paw withdrawal thermal latency (PWTL) measurements. SIRT2 and binding adaptor molecule 1 (Iba1) protein expressions and localization in spinal cord samples were detected by western blot and immunofluorescence. The results revealed SIRT2 downregulation in the spinal cord of rats with Remi-stimulated POH. Intrathecal administration of the overexpression plasmid harboring SIRT2 remarkably relieved mechanical allodynia, along with thermal hyperalgesia in the model animals. Iba1 amounts were increased upon intraoperative incision or Remi infusion, and this effect was more pronounced upon combining both treatments. Furthermore, SIRT2 overexpression suppressed microglia activation in the spinal cord of model animals, and starkly relieved incision- and/or Remi-associated pronociceptive processes as well as spinal microglia activation. SIRT2 elevation relieved Remi-associated POH, likely by suppressing spinal microglia activation. Thus, SIRT2 could be a potent target for treating neuropathic pain.

Out-of-hospital opioid prescriptions after knee and hip arthroplasty: prescribers and the first prescribed opioid.

BACKGROUND: We determined the first prescribed opioid and the prescribers of opioids after knee and hip arthroplasty (KA/HA) between 2013 and 2018 in the Netherlands. We also evaluated whether the first prescribed opioid dose was associated with the total dispensed dose and long-term opioid use in the first postoperative year. METHODS: The Dutch Foundation for Pharmaceutical Statistics was linked to the Dutch Arthroplasty Register. Stratified for KA/HA, the first out-of-hospital opioid within 30 days of operation was quantified as median morphine milligram equivalent (MME). Opioid prescribers were orthopaedic surgeons, general practitioners, rheumatologists, anaesthesiologists, and other physicians. Long-term use was defined as ≥1 opioid prescription for >90 postoperative days. We used linear and logistic regression analyses adjusted for confounders. RESULTS: Seventy percent of 46 106 KAs and 51% of the 42 893 HAs were prescribed ≥1 opioid. Oxycodone increased as first prescribed opioid (from 44% to 85%) whereas tramadol decreased (64-11%), but their dosage remained stable (stronger opioids were preferred by prescribers). An increase in the first prescription of 1% MME resulted in a 0.43%/0.37% increase in total MME (KA/HA, respectively). A 100 MME increase in dose of the first dispensed opioid had a small effect on long-term use (prevalence: 25% KA, 20% HA) (odds ratio=1.02/1.01 for KA/HA, respectively). Orthopaedic surgeons increasingly prescribed the first prescription between 2013 and 2018 (44-69%). General practitioners mostly prescribed consecutive prescriptions (>50%). CONCLUSION: Oxycodone increased as first out-of-hospital prescription between 2013 and 2018. The dose of the first prescribed opioid was associated with the total dose and a small increased risk of prolonged use. First prescriptions were mostly written by orthopaedic surgeons and consecutive prescriptions by general practitioners.

Analgesic efficacy of systemic lidocaine using lean body mass based dosing regime versus placebo in bariatric surgery: a prospective, randomised, double-blind, placebo-controlled, single-centre study.

BACKGROUND: Intravenous lidocaine is used as an adjuvant analgesic agent in perioperative settings. It has been investigated in various patient populations and surgical interventions, but there are limited data on its efficacy, particularly for patients undergoing bariatric surgery. Obese patients are at high risk of postoperative respiratory complications and can be expected to benefit from anaesthetic techniques that minimise opioid administration. METHODS: We studied administration of lidocaine hydrochloride 1% i.v. to general anaesthesia at a dose of 1.5 mg kg-1 (lean body mass×1.28) or placebo in patients undergoing bariatric surgery. Subjects randomly assigned to each group were surveyed for 48 h after surgery for experienced pain (primary outcome), and administered opioids, postoperative nausea and vomiting (PONV), resumption of bowel function, and length of hospital stay (secondary outcomes). RESULTS: We recruited and randomised 140 subjects to either the lidocaine or placebo group; 137 completed the study. Subjects with pain numeric rating scale (NRS) >3 within the first 4 h postoperatively were similar in both groups (proportion of any NRS >3 within first 4 h lidocaine group: 47/68 (69%) vs placebo group: 44/69 (63%), P=0.507; within first h P=0.177, within second h P=0.513, within third h P=0.145, within fourth h P=0.510). There was no difference in maximal pain score, opioid consumption, recovery of bowel function, incidence of PONV, or length of hospital stay. CONCLUSIONS: Lidocaine does not improve postoperative pain scores, analgesia, or any secondary outcomes in patients undergoing bariatric surgery. CLINICAL TRIAL REGISTRATION: NCT03667001.

Therapeutic efficacy of intravenous lidocaine infusion compared with thoracic epidural analgesia in major abdominal surgery: a noninferiority randomised clinical trial.

BACKGROUND: Open major abdominal surgery is one of the most risky surgical procedures for acute postoperative pain. Thoracic epidural analgesia (TEA) has been considered the standard analgesic approach. In different reports, lidocaine i.v. has been shown to have an analgesic efficacy comparable with TEA. We compared the analgesic efficacy of i.v. lidocaine with thoracic epidural analgesia using bupivacaine in patients undergoing major abdominal surgery. METHODS: In this noninferiority clinical trial, 210 patients were randomised to thoracic epidural bupivacaine with morphine or i.v. lidocaine. Dynamic pain at 24 h after surgery was measured using a numerical pain rating scale (NPR), and morphine consumption was also measured. A difference in i.v. the lidocaine-epidural bupivacaine NPR of ≤1 for dynamic pain was considered a noninferiority margin. RESULTS: The NPR for dynamic pain in the lidocaine group at 24 h was between 5.7 (1.8) and 5.2 (1.9) in the epidural group, with a difference of 0.53 (95% confidence interval 0.0-1.0). In the first 24 h, the average difference in morphine consumption was 1.8 mg between the i.v. lidocaine and epidural groups (95% confidence interval 1-3 mg). No differences were found in adverse events or complications associated with the procedures. CONCLUSIONS: Intravenous lidocaine is noninferior to thoracic epidural analgesia for acute postoperative pain control in major abdomial surgery at 24 h postoperatively. CLINICAL TRIALS REGISTRATION: NCT04017013.

Discharge of postoperative patients with an opioid prescription is associated with increased persistent opioid use, healthcare expenditures and mortality: a retrospective cohort study.

BACKGROUND: The risk factors for persistent opioid use after surgical discharge and the association between opioid prescription at discharge and postoperative emergency department visits, readmission, and mortality are unclear. METHODS: This population-based retrospective cohort study involved opioid-naive patients who underwent surgical procedures from January 1, 2000 to November 30, 2020. The data source was Hong Kong Hospital Authority Clinical Management System electronic health record. The primary outcome was the incidence of new persistent opioid use. Other study outcomes included 30-day emergency department visits, 30-day readmission, and 30-day all-cause mortality. Multivariable logistic regression models were used to estimate the association between opioid prescription at discharge and persistent opioid use, emergency department visits, readmission, and all-cause mortality. RESULTS: Over a median follow-up of 1 month with 36 104 person-years, 438 128 patients (opioid prescription: 32 932, no opioid prescription: 405 196) who underwent surgical procedures were analysed, of whom 15 112 (3.45%) had persistent opioid use after discharge. Prescribing opioids on discharge was associated with increased risks of developing persistent opioid use (odds ratio [OR]: 2.30, 95% confidence interval [CI]: 2.19-2.40, P<0.001), 30-day emergency department visits (OR: 1.28, 95% CI: 1.23-1.33, P<0.001), 30-day readmission (OR: 1.17, 95% CI: 1.13-1.20, P<0.001), and 30-day all-cause mortality (OR: 1.68, 95% CI: 1.53-1.86, P<0.001). CONCLUSIONS: In this large cohort of patients undergoing surgery, an opioid prescription on discharge was associated with a higher chance of persistent opioid use and increased risks of postoperative emergency department visits, readmission, and mortality. Minimising opioid prescriptions on discharge could improve perioperative patient outcomes.

Oral pregabalin is effective as preemptive analgesia in abdominal hysterectomy-A randomized controlled trial.

Postoperative pain is one of the main negative symptoms resulting from surgery and the use of new methods to control this symptom is of ever-increasing relevance. Opioid-sparing strategies, such as multimodal analgesia, are trends in this scenario. Pregabalin is a well-established treatment for neuropathic pain; however, it is still controversial in the surgical context for postoperative analgesia. This study investigated the effect of pregabalin on postoperative analgesia in patients undergoing abdominal hysterectomy. It is a prospective, randomised, double-blind, placebo-controlled clinical trial. Female patients undergoing abdominal hysterectomy were randomised to use pregabalin (group P1), 300 mg orally 2 h before surgery, or identical placebo pills (group P0). The main outcome includes the postoperative pain index by visual analogue scale (VAS) and McGill's pain questionnaire. Secondary outcomes include opioid consumption and the presence of adverse effects. A value of p < 0.05 was used to reject type I error. Fifty-five patients were randomised amongst the groups. Patients in group P1 had lower pain rates by VAS scale, both at rest and in active motion, than group P0. In McGill's questionnaire, patients from group P1 also had lower pain rates (12 × 28.5). There was approximately twice as much opioid consumption amongst patients in group P0. Regarding side effects, there was a difference between the two groups only for dizziness, being more incident in group P1. This study suggests that pregabalin is an important adjuvant drug in treating postoperative pain in patients with abdominal hysterectomy.

Minimal important difference in opioid consumption based on adverse event reduction-A study protocol.

BACKGROUND: The patient-relevant minimal important difference for opioid consumption remains undetermined, despite its frequent use as primary outcome in trials on postoperative pain management. A minimal important difference is necessary to evaluate whether significant trial results are clinically relevant. Further, it can be used as effect size to ensure that trials are powered to find clinically relevant effects. By exploring the dose-response relationship between postoperative opioid consumption and opioid-related adverse effects, we aim to approximate the minimal important difference in opioid consumption anchored to opioid-related adverse effects. METHODS: This is a post-hoc analysis of aggregated data from two clinical trials (PANSAID NCT02571361 and DEX2TKA NCT03506789) and one observational cohort study (Pain Map NCT02340052) on pain management after total hip and knee arthroplasty. The primary outcome is the Hodges-Lehmann median difference in opioid consumption between patients with no opioid-related adverse effects and patients experiencing the mildest degree of one or more opioid-related adverse effects (i.e., mild nausea, sedation and/or dizziness or vomiting). Secondary outcomes include the Hodges-Lehmann median difference in opioid consumption that corresponds to one point on a cumulated opioid-related adverse event 0-10 scale. Further, we will explore the proportion of patients that experience opioid-related adverse effects for consecutive opioid dose intervals of 2 mg iv morphine equivalents. Quantile regression will be used to assess any significant interactions with patient baseline characteristics. CONCLUSIONS: This study will hopefully bring us one step closer to determining relevant opioid reductions and thereby improve our understanding of intervention effects and planning of future trials.

Glucocorticoids added to paracetamol and NSAIDs for post-operative pain: A systematic review with meta-analysis and trial sequential analysis.

BACKGROUND: Paracetamol and non-steroidal anti-inflammatory drugs (NSAIDs) are recommended as the basic pain treatment regimen for most surgeries. Glucocorticoids have well-known anti-inflammatory and anti-emetic properties and may also demonstrate analgesic effects. We assessed benefit and harm of adding glucocorticoids to a combination of paracetamol and NSAIDs for post-operative pain management. METHODS: We searched Embase, Medline and CENTRAL for randomised clinical trials investigating the addition of glucocorticoids versus placebo/no intervention to paracetamol and an NSAID in adults undergoing any type of surgery. We assessed three primary outcomes: cumulative opioid consumption at 24 h postoperatively, serious adverse events and pain at rest at 24 h postoperatively. We performed meta-analysis and trial sequential analysis (TSA), assessed risk of bias using the Risk of Bias 2 tool and used the Grading of Recommendations Assessment, Development and Evaluation approach to evaluate the certainty of the evidence. RESULTS: We identified 12 relevant trials of which nine trials randomising 804 participants were included in quantitative analysis. When added to paracetamol and NSAIDs, we found no evidence of a difference of glucocorticoids versus placebo/no intervention in cumulative opioid consumption at 24 h postoperatively (mean difference [MD] -0.28, TSA-adjusted 95% confidence interval [CI] -1.90 to 1.33, p = .68, moderate certainty of evidence), serious adverse events (risk ratio (RR) 0.99, TSA-adjusted 95% CI 0.27-3.63, p = .93, very low certainty of evidence) or pain on the Numeric Rating Scale at 24 h postoperatively (MD -0.39, TSA-adjusted 95% CI -0.84 to 0.17, p = .10, moderate certainty of evidence). All outcomes were assessed to be at high risk of bias and TSA showed that we had insufficient information for most outcomes. CONCLUSION: Glucocorticoids added to a baseline therapy of paracetamol and an NSAID likely result in little to no difference in cumulative opioid consumption and pain at rest at 24 h postoperatively. In addition, the evidence is very uncertain about the effect on serious adverse events. For most outcomes we did not have sufficient information to draw firm conclusions and the certainty of the evidence varied from moderate to very low. EDITORIAL COMMENT: Multimodal approaches for post-operative analgesia are favoured, including paracetamol and nonsteroidal anti-inflammatory drugs. In this meta-analysis, pooled results from clinical trials are assessed to describe possible benefit of addition of glucocorticoid treatment for analgesia. The findings did not identify additional benefit, though the certainty of the evidence was not high.

An individualised tapering protocol reduces opioid use 1 year after spine surgery: A randomised controlled trial of patients with preoperative opioid use.

BACKGROUND: Persistent opioid use following surgery is common especially in patients with preoperative opioid use. This study aims to determine the long-term effect of an individualised opioid tapering plan versus standard of care in patients with a preoperative opioid use undergoing spine surgery at Aarhus University Hospital, Denmark. METHODS: This is the 1-year follow-up of a prospective, single-centre, randomised trial of 110 patients who underwent elective spine surgery for degenerative disease. The intervention was an individualised tapering plan at discharge and telephone counselling 1 week after discharge, compared to standard of care. Postoperative outcomes after 1 year include opioid use, reasons for opioid use and pain intensity. RESULTS: The overall response rate to the 1-year follow-up questionnaire was 94% (intervention group 52/55 patients and control group 51/55 patients). Forty-two patients (proportion = 0.81, 95% CI 0.67-0.89) in the intervention group compared to 31 (0.61, 95% CI 0.47-0.73; p = .026) patients in the control group succeeded in tapering to zero 1 year after discharge (p = .026). One patient (0.02, 95% CI 0.01-0.13) in the intervention group compared to seven patients (0.14, 95% CI 0.07-0.26) in the control group were unable to taper to their preoperative dose 1 year after discharge (p = .025). Back/neck and radicular pain intensity was similar between study groups. CONCLUSION: These results suggest that an individualised tapering plan at discharge combined with telephone counselling 1 week after discharge can reduce opioid use 1 year after spine surgery.

Addition of preoperative transversus abdominis plane block to multimodal analgesia in open gynecological surgery: a randomized controlled trial.

BACKGROUND: Transversus abdominis plane (TAP) block can provide effective analgesia for abdominal surgery. However, it was questionable whether TAP had additional effect in the context of multimodal analgesia (MMA). Therefore, this study aimed to assess the additional analgesic effect of preoperative TAP block when added to MMA protocol in open gynecological surgery. METHODS: In this prospective, randomized-controlled trial, 64 patients scheduled for open gynecological surgery were randomized to receive preoperative TAP block (Study group, n = 32) or placebo (Control group, n = 32) in addition to MMA protocol comprising dexamethasone, acetaminophen, flurbiprofen and celecoxib, and rescued morphine analgesia. The primary outcome was rescued morphine within 24 h after surgery. Secondary outcomes included pain scores, adverse effects, quality of recovery measured by 40-item quality of recovery questionnaire score (QoR-40) at 24 h, and quality of life measured with short-form health survey (SF - 36) on postoperative day (POD) 30. RESULTS: The Study group had less rescued morphine than the control group within 24 h [5 (2-9) vs. 8.5 (5-12.8) mg, P = 0.013]. The Study group had lower pain scores at 1 h [3 (2-4) vs. 4 (3-5), P = 0.007], 2 h [3 (2-4) vs. 3.5 (3-5), P = 0.010] and 6 h [3 (2-3) vs. 3 (2.3-4), P = 0.028], lower incidence of nausea at 48 h (25.8% vs. 50%, P = 0.039), and higher satisfaction score [10 (10-10) vs. 10 (8-10), P = 0.041]. The SF-36 bodily pain score on POD 30 was higher in the Study group (59 ± 13 vs. 49 ± 16, P = 0.023). CONCLUSIONS: Preoperative TAP block had additional analgesic effect for open gynecological surgery when used as part of multimodal analgesia. Rescued morphine within 24 h was significantly reduced and the SF-36 bodily pain dimension at 30 days after surgery was significantly improved. TRIAL REGISTRATION: www.chictr.org.cn (ChiCTR2000040343, on Nov 28 2020).

Comparison of postoperative nausea and vomiting between Remimazolam and Propofol in Patients undergoing oral and maxillofacial surgery: a prospective Randomized Controlled Trial.

BACKGROUND: Remimazolam is a recently approved, ultra-short-acting benzodiazepine. However, few studies have investigated remimazolam in relation to postoperative nausea and vomiting (PONV). This study aimed to compare the effects of remimazolam and propofol on PONV in patients undergoing oral and maxillofacial surgery. METHODS: Patients (n = 206) aged 19-65 years who were scheduled for oral and maxillofacial surgery were randomized into two groups, the remimazolam (R) and propofol group (P). In the R group (n = 94), remimazolam was used to induce anesthesia at 12 mg/kg/h and to maintain anesthesia at 1-2 mg/kg/h. In the P group (n = 95), anesthesia was induced and maintained with propofol (target effect-site concentration: 3-5 µg/ml). In both groups, remifentanil was administered at a target effect-site concentration of 2.5-4 ng/ml. The primary outcome was the overall incidence of PONV during the first 24 h after surgery. Secondary outcomes included the severity of nausea, use of rescue antiemetics, severity of postoperative pain, use of rescue analgesia, and quality of recovery. RESULTS: The incidence of PONV during the first 24 h after surgery was 11.7% and 10.5% in the R group and P group, respectively, and there was no significant difference in the severity of nausea (P > 0.05). Ten patients in the R group and ten patients in the P group required rescue antiemetics during the first 24 h after surgery (P = 0.98). No inter-group differences were observed in terms of postoperative pain score, use of rescue analgesia, and quality of recovery (P > 0.05). CONCLUSIONS: In this study, remimazolam did not increase the incidence and severity of PONV compared with propofol. TRIAL REGISTRATION: KCT0006965, Clinical Research Information Service (CRIS), Republic of Korea. Registration date: 26/01/2022.