Cannabis use and acute postoperative pain outcomes in older adults: a propensity matched retrospective cohort study.

INTRODUCTION: Cannabis use is increasing among older adults, but its impact on postoperative pain outcomes remains unclear in this population. We examined the association between cannabis use and postoperative pain levels and opioid doses within 24 hours of surgery. METHODS: We conducted a propensity score-matched retrospective cohort study using electronic health records data of 22 476 older surgical patients with at least 24-hour hospital stays at University of Florida Health between 2018 and 2020. Of the original cohort, 2577 patients were eligible for propensity-score matching (1:3 cannabis user: non-user). Cannabis use status was determined via natural language processing of clinical notes within 60 days of surgery and structured data. The primary outcomes were average Defense and Veterans Pain Rating Scale (DVPRS) score and total oral morphine equivalents (OME) within 24 hours of surgery. RESULTS: 504 patients were included (126 cannabis users and 378 non-users). The median (IQR) age was 69 (65-72) years; 295 (58.53%) were male, and 442 (87.70%) were non-Hispanic white. Baseline characteristics were well balanced. Cannabis users had significantly higher average DVPRS scores (median (IQR): 4.68 (2.71-5.96) vs 3.88 (2.33, 5.17); difference=0.80; 95% confidence limit (CL), 0.19 to 1.36; p=0.01) and total OME (median (IQR): 42.50 (15.00-60.00) mg vs 30.00 (7.50-60.00) mg; difference=12.5 mg; 95% CL, 3.80 mg to 21.20 mg; p=0.02) than non-users within 24 hours of surgery. DISCUSSION: This study showed that cannabis use in older adults was associated with increased postoperative pain levels and opioid doses.

Effects of popliteal plexus block after total knee arthroplasty: a randomized clinical trial.

BACKGROUND AND OBJECTIVES: Motor-sparing peripheral nerve blocks enhance multimodal opioid-sparing strategies after total knee arthroplasty. We hypothesized that adding a popliteal plexus block to a femoral triangle block could reduce 24-hour opioid consumption after total knee arthroplasty, compared with standalone femoral triangle block or adductor canal block. METHODS: This patient- and assessor-blinded, randomized controlled trial allocated 165 patients into three equally sized parallel groups, receiving either 1) popliteal plexus block+femoral triangle block, 2) femoral triangle block, or 3) adductor canal block. Intravenous oxycodone was administered via patient-controlled analgesia pumps. The primary outcome was 24-hour postoperative opioid consumption. Secondary outcomes were preoperative maximum voluntary isometric contraction and manual muscle tests of knee and ankle movement assessed before and after the nerve block procedure together with postoperative pain scores, mobilization, and 12-hour opioid consumption. RESULTS: 24-hour postoperative intravenous oxycodone consumption varied significantly between groups (p<0.01), with medians (IQR) of 6 mg (2-12) in the popliteal plexus block+femoral triangle block group, 10 mg (8-16) in the femoral triangle block group, and 12 mg (6-18) in the adductor canal block group. Median consumption in the popliteal plexus block+femoral triangle block group was reduced by -4 mg (95% CI -7.4 to -1.0, p<0.01) and -6 mg (95% CI -8.3 to -1.3, p=0.01) compared with groups of femoral triangle block and adductor canal block, respectively. No differences were found in pain scores, mobilization, or changes in preoperative muscle strength. Post hoc analysis revealed successful 24-hour opioid-free postoperative care among 12 patients with popliteal plexus block+femoral triangle block, as compared with two with femoral triangle block and six with adductor canal block. CONCLUSION: Adding a popliteal plexus block to a femoral triangle block resulted in a statistically significant reduction of 24-hour postoperative opioid consumption after total knee arthroplasty. However, no differences were found in pain scores. Popliteal plexus block did not impair the lower leg muscles.

Individuals With Prior Chronic Pain and Long-Term Opioid Treatment May Experience Persistence of That Pain Even After Subsequent Complete Cervical Spinal Cord Injury: Suggestions From a Prospective Case-Controlled Study.

Objective: To determine whether chronic pain persists after complete spinal cord injury (SCI). Design: Prospective observational study regarding the outcome of pre-existent chronic pain of inpatients admitted with new clinically diagnosed complete cervical SCI. For patients who acknowledged chronic pain of ≥3 years duration before the SCI, further questions explored whether they still experienced that pain, whether they were experiencing current posttraumatic pain, and whether they had any past exposure to opioids. The included patients were identified during the initial consultation in the trauma center for treatment of the SCI. Setting: Level I trauma center. Participants: From a total of 49 participants with acute cervical SCI with clinically diagnosed complete motor and sensory tetraplegia admitted between 2018 and 2020, 7 were selected on the basis of a history of chronic pain. Intervention: Collected complete history and performed physical examination with serial follow-ups during the acute hospital stay until death or discharge. Main Outcome Measures: The primary outcome was a finding of chronic pain experienced before new clinical diagnosis of complete SCI, compared with whether or not that pain continued after the SCI injury. The secondary outcome was the relation of persistent pain with opioid use; it was formulated after data collection. Results: Among 49 patients with clinically diagnosed complete cervical SCIs, 7 had experienced prior chronic pain. Four participants experienced a continuation of the prior pain after their complete tetraplegia (4/7), whereas 3 participants did not (3/7). All the participants with continued pain had been previously treated with opioids, whereas those whose pain ceased had not received chronic opioid therapy. Conclusions: There may be a unique form of chronic pain that is based in the brain, irrespective of peripheral pain or spinal mechanisms. Otherwise healthy people with longstanding antecedent chronic pain whose pain persists after acute clinically complete SCI with tetraplegia may provide a new model for evaluation of brain-based pain. Opioids may be requisite for this type of pain.

Opioid and non-opioid analgesic regimens after fracture and risk of serious opioid-related events.

Background: Non-opioid analgesics are prescribed in combination with opioids among patients with long bone fracture to reduce opioid prescribing needs, yet evidence is limited on whether they reduce the risk of serious opioid-related events (SOREs). We compared the risk of SOREs among hospitalized patients with long bone fracture discharged with filled opioid prescriptions, with and without non-opioid analgesics. Design: We identified a retrospective cohort of analgesic-naïve adult patients with a long bone fracture hospitalization using the Merative MarketScan Commercial Database (2013-2020). The exposure was opioid and non-opioid analgesic (gabapentinoids, muscle relaxants, non-steroidal anti-inflammatory drugs, acetaminophen) prescriptions filled in the 3 days before through 42 days after discharge. The outcome was the development of new persistent opioid use or opioid use disorder during follow-up (day 43 through day 408 after discharge). We used Cox proportional hazards regression with inverse probability of treatment weighting with overlap trimming to compare outcomes among those that filled an opioid and a non-opioid analgesic to those that filled only an opioid analgesic. In secondary analyses, we used separate models to compare those that filled a prescription for each specific non-opioid analgesic type with opioids to those that filled only opioids. Results: Of 29 489 patients, most filled an opioid prescription alone (58.4%) or an opioid and non-opioid (22.0%). In the weighted proportional hazards regression model accounting for relevant covariates and total MME, filling both a non-opioid analgesic and an opioid analgesic was associated with 1.63 times increased risk of SOREs compared with filling an opioid analgesic only (95% CI 1.41 to 1.89). Filling a gabapentin prescription in combination with an opioid was associated with an increased risk of SOREs compared with those that filled an opioid only (adjusted HR: 1.84 (95% CI1.48 to 2.27)). Conclusions: Filling a non-opioid analgesic in combination with an opioid was associated with an increased risk of SOREs after long bone fracture. Level of evidence: Level III, prognostic/epidemiological. Study type: Retrospective cohort study.

Effect of an opioid-free anesthetic on postoperative opioid consumption after laparoscopic bariatric surgery: a prospective, single-blinded, randomized controlled trial.

INTRODUCTION: Opioid administration has the benefit of providing perioperative analgesia but is also associated with adverse effects. Opioid-free anesthesia (OFA) may reduce postoperative opioid consumption and adverse effects after laparoscopic bariatric surgery. In this randomized controlled study, we hypothesized that an opioid-free anesthetic using lidocaine, ketamine, and dexmedetomidine would result in a clinically significant reduction in 24-hour postoperative opioid consumption when compared with an opioid-inclusive technique. METHODS: Subjects presenting for laparoscopic or robotic bariatric surgery were randomized in a 1:1 ratio to receive either standard opioid-inclusive anesthesia (group A: control) or OFA (group B: OFA). The primary outcome was opioid consumption in the first 24 hours postoperatively in oral morphine equivalents (OMEs). Secondary outcomes included postoperative pain scores, patient-reported incidence of opioid-related adverse effects, hospital length of stay, patient satisfaction, and ongoing opioid use at 1 and 3 months after hospital discharge. RESULTS: 181 subjects, 86 from the control group and 95 from the OFA group, completed the study per protocol. Analysis of the primary outcome showed no significant difference in total opioid consumption at 24 hours between the two treatment groups (control: 52 OMEs vs OFA: 55 OMEs, p=0.49). No secondary outcomes showed statistically significant differences between groups. CONCLUSIONS: This study demonstrates that an OFA protocol using dexmedetomidine, ketamine, and lidocaine for laparoscopic or robotic bariatric surgery was not associated with a reduction in 24-hour postoperative opioid consumption when compared with an opioid-inclusive technique using fentanyl.

At a Crossroads: Opioid Use Disorder, the X-Waiver, and the Road Ahead.

Background: Buprenorphine/naloxone (Suboxone) is widely considered the first-line treatment for opioid use disorder (OUD), which causes significant morbidity and mortality in the United States, but prior to 2023, practitioners interested in prescribing buprenorphine/naloxone for OUD needed a special Drug Enforcement Administration certification (the X-Waiver) that imposed a patient cap and other limitations. The Consolidated Appropriations Act of 2023 considerably decreased the restrictions on prescribing practitioners. Buprenorphine/naloxone can now be prescribed like any other prescription opioid, excluding methadone. The historic context for the opioid crisis, OUD, the X-Waiver, and additional initiatives that may be needed beyond legislative change to effectively address OUD are the subjects of this review. Methods: To develop this review of the opioid crisis, OUD, and OUD treatment, we conducted a literature search of the PubMed database and constructed a timeline of the opioid crisis and changes in OUD treatment, specifically the X-Waiver, to characterize the historic context of OUD and the X-Waiver against the background of the opioid crisis. Results: The opioid crisis has had pervasive public health and economic impacts in the United States. Major changes to the treatment of OUD have occurred as a result of the Drug Addiction Treatment Act of 2000 that imposed the X-Waiver and the Consolidated Appropriations Act of 2023 that repealed the X-Waiver. Conclusion: The repeal of the X-Waiver is predicted to increase the accessibility of buprenorphine/naloxone in the United States. However, additional work beyond legislative change, including institutional support and reduction of stigma and disparities, is needed to substantially improve outcomes for OUD patients.

Relationship between intraoperative requirement for anesthetics and postoperative analgesic consumption in laparoscopic colectomy: a randomized controlled double-blinded study.

BACKGROUND: This study investigated the relationship between intraoperative requirement for an inhalational anesthetic (sevoflurane) or an opioid (remifentanil) and postoperative analgesic consumption. METHODS: The study included 200 adult patients undergoing elective laparoscopic colectomy. In the sevoflurane group, the effect-site concentration of remifentanil was fixed at 1.0 ng/ml, while the inspiratory sevoflurane concentration was adjusted to maintain an appropriate anesthetic depth. In the remifentanil group, the end-expiratory sevoflurane concentration was fixed at 1.0 vol.%, and the remifentanil concentration was adjusted. Pain scores and cumulative postoperative analgesic consumptions were evaluated at 2, 6, 24, and 48 h after surgery. RESULTS: Average end-tidal concentration of sevoflurane and effect-site concentration of remifentanil were 2.0 ± 0.4 vol.% and 3.9 ± 1.4 ng/ml in the sevoflurane and remifentanil groups, respectively. Cumulative postoperative analgesic consumption at 48 h postoperatively was 55 ± 26 ml in the sevoflurane group and 57 ± 33 ml in the remifentanil group. In the remifentanil group, the postoperative cumulative analgesic consumptions at 2 and 6 h were positively correlated with intraoperative remifentanil requirements (2 h: r = 0.36, P < 0.001; 6 h: r = 0.38, P < 0.001). However, there was no significant correlation in the sevoflurane group (r = 0.04, P = 0.691). CONCLUSIONS: The amount of intraoperative requirement of short acting opioid, remifentanil, is correlated with postoperative analgesic consumption within postoperative 6 h. It may be contributed by the development of acute opioid tolerance. However, intraoperative sevoflurane requirement had no effect on postoperative analgesic consumption.

Impact of Depressive Symptom Severity on Buprenorphine/Naloxone and Methadone Outcomes in People With Prescription-Type Opioid Use Disorder: Results From a Pragmatic Randomized Controlled Trial.

OBJECTIVE: To evaluate the impact of depressive symptom severity on opioid use and treatment retention in individuals with prescription-type opioid use disorder (POUD). METHOD: We analyzed data from a multi-centric, pragmatic, open-label, randomized controlled trial comparing buprenorphine/naloxone to methadone models of care in 272 individuals with POUD. Opioid use was self-reported every two weeks for 24 weeks using the Timeline Followback. Depressive symptom severity was self-reported with the Beck Depression Inventory at baseline, week 12 and week 24. RESULTS: Baseline depressive symptom severity was not associated with opioid use nor treatment retention. At week 12, moderate depressive symptoms were associated with greater opioid use while mild to severe depressive symptoms were associated with lowered treatment retention. At week 24, moderate depressive symptoms were associated with greater opioid use. CONCLUSIONS: Ongoing depressive symptoms lead to poorer outcomes in POUD. Clinicians are encouraged to use integrative approaches to optimize treatment outcomes. This study was registered in ClinicalTrials.gov (NCT03033732) on January 27th, 2017, prior to participants enrollment.

[Pharmacological pain management in cancer patients]. / Medikamentöse Schmerztherapie bei Patienten mit Tumorerkrankungen.

Pharmacological pain therapy in cancer patients is based on guideline recommendations, which, however, do not fully coincide in all aspects due to varying weighting of evidence. The present article discusses current issues including the decreasing significance of the World Health Organization (WHO) analgesic ladder, with its distinction between step 2 and 3 being increasingly questioned. Risks of nonopioid analgesics such as paracetamol and nonsteroidal anti-inflammatory drugs (NSAIDs), particularly in older populations, are discussed. Paracetamol may potentially reduce the effectiveness of immunotherapies. Aspects of administering analgesics via a feeding tube are considered. Recommendations for the treatment of episodic pain, transitioning between different opioids, and some relevant interactions are also discussed.

Postsurgical opioid prescribing among veterans using community care for orthopedic surgery at non-VA hospitals compared to a VA hospital with a transitional pain service: a retrospective cohort study.

BACKGROUND: The USA provides medical services to its military veterans through Veterans Health Administration (VHA) medical centers. Passage of recent legislation has increased the number of veterans having VHA-paid orthopedic surgery at non-VHA facilities. METHODS: We conducted a retrospective cohort study among veterans who underwent orthopedic joint surgery paid for by the VHA either at the Salt Lake City VHA Medical Center (VAMC) or at non-VHA hospitals between January 2018 and December 2021. 562 patients were included in the study, of which 323 used a non-VHA hospital and 239 patients the VAMC. The number of opioid tablets prescribed at discharge, the total number prescribed by postdischarge day 90, and the number of patients still filling opioid prescriptions between 90 and 120 days after surgery were compared between groups. RESULTS: Veterans who underwent orthopedic surgery at a non-VHA hospital were prescribed more opioid tablets at discharge (median (IQR)); (40 (30-60) non-VHA vs 30 (20-47.5) VAMC, p<0.001) and in the first 90 days after surgery than patients who had surgery at the Salt Lake City VAMC (60 (40-120) vs 35 (20-60), p<0.001). Patients who had surgery at Salt Lake City VAMC were also significantly less likely to fill opioid prescriptions past 90 days after hospital discharge (OR (95% CI) 0.06 (0.01 to 0.48), p=0.007). CONCLUSION: These results suggest that veterans who have surgery at a veterans affairs hospital with a transitional pain service are at lower risk for larger opioid prescriptions both at discharge and within 90 days after surgery as well as persistent opioid use beyond 90 days after discharge than if they have surgery at a community hospital.

Predictors of opioid use for rib fractures in a regional Australian hospital.

BACKGROUND: Rib fractures (RFs) are the leading type of single serious injury in New South Wales trauma patients. Uncontrolled pain drives the sequelae of atelectasis, pneumonia, respiratory failure, and death in severe cases. Opioids are the mainstay of management; however, they carry numerous adverse effects. Understanding patient or injury factors which predict opioid requirement is important to tailor management. Existing evidence is limited to metropolitan trauma centres (MTCs). METHODS: We conducted an observational, retrospective, single-centre cohort study of all admissions to Albury Wodonga Health diagnosed with one or more RFs and discharged between January 1st, 2017, and December 31st, 2022, inclusive. Data collected included demographics, injury characteristics, and management, including analgesia. LASSO regression was performed to determine predictors of average daily opioid use for the first five days of admission in oral morphine equivalents (mg). R2 and root mean square error (RMSE) were calculated to assess model performance. RESULTS: We included 624 patients. LASSO selected number of RFs, fracture displacement score, pulmonary contusion, new injury severity score, age, chest tube use, chronic pain history, opioid history and upper or middle lateral RF location categories as predictors. Sex, middle anterior, middle posterior, and lower RF location categories were excluded by LASSO. The out of sample R2 was 28.6 %. On the scale of log OME, the RMSE was 1.08. CONCLUSION: The model is effective at identifying predictors of opioid use in this regional centre, which are similar to those described in evidence from MTCs. However, the low R2 with wide prediction intervals limits its utility on an individual level.

"To prescribe or not to prescribe, that is the question": Perspectives on opioid prescribing for chronic, cancer-related pain from clinicians who treat pain in survivorship.

BACKGROUND: Opioid pain management in cancer survivorship is a complex and understudied topic. METHODS: The authors conducted in-depth, qualitative interviews to understand clinician approaches to opioid pain management in chronic cancer pain and to generate ideas for improvement. They used a rigorous, inductive, qualitative, descriptive approach to examine clinician (n = 20) perspectives about opioid pain management in survivorship, including oncologists (n = 5), palliative care clinicians (n = 8), primary care clinicians (n = 5), and pain management specialists (n = 2). RESULTS: The findings indicated that no consistent medical home exists for chronic pain management in cancer survivors and that there are fundamental differences in how each subspecialty approaches chronic pain management in survivorship (e.g., "Do we think of this as noncancer pain or cancer pain?… This is in this limbo zone-this gray zone-because it's cancer-related pain, right?"). Simultaneously, clinicians are influenced by their peers' perceptions of their opioid prescribing decisions, sparking intraprofessional tension when disagreement occurs. In these instances, clinicians described overthinking and doubting their clinical decision-making as well as a sense of judgment, pressure, and/or shame. Finally, clinicians acknowledged a fear of consequences for opioid prescribing decisions. Specifically, participants cited conflict with patients, sometimes escalating to aggression and threats of violence, as well as potential disciplinary actions and/or legal consequences. CONCLUSIONS: Participants suggested that opportunities to improve chronic cancer pain care include developing clear, systematic guidance for chronic cancer pain management, facilitating clinician communication and consultation, creating tailored survivorship care plans in partnership with patients, and developing accessible, evidence-based, complementary pain treatments.

Multisite prospective study of perioperative pain management practices for anterior cruciate ligament reconstruction in adolescents: Society for Pediatric Anesthesia Improvement Network (SPAIN) Project Report.

INTRODUCTION: Although 200 000 adolescents undergo anterior cruciate ligament reconstruction (ACLR) surgery annually, no benchmarks for pediatric post-ACLR pain management exist. We created a multicenter, prospective, observational registry to describe pain practices, pain, and functional recovery after pediatric ACLR. METHODS: Participants (n=519; 12-17.5 years) were enrolled from 15 sites over 2 years. Data on perioperative management and surgical factors were collected. Pain/opioid use and Lysholm scores were assessed preoperatively, on postoperative day 1 (POD1), POD3, week 6, and month 6. Descriptive statistics and trends for opioid use, pain, and function are presented. RESULTS: Regional analgesia was performed in 447/519 (86%) subjects; of these, adductor canal single shot was most frequent (54%), nerve catheters placed in 24%, and perineural adjuvants used in 43%. On POD1, POD3, week 6, and month 6, survey response rates were 73%, 71%, 61%, and 45%, respectively. Over these respective time points, pain score >3/10 was reported by 64% (95% CI: 59% to 69%), 46% (95% CI: 41% to 52%), 5% (95% CI: 3% to 8%), and 3% (95% CI: 1% to 6%); the number of daily oxycodone doses used was 2.8 (SD 0.19), 1.8 (SD 0.13), 0, and 0. There was considerable variability in timing and tests for postdischarge functional assessments. Numbness and weakness were reported by 11% and 4% at week 6 (n=315) and 16% and 2% at month 6 (n=233), respectively. CONCLUSION: We found substantial variability in the use of blocks to manage post-ACLR pain in children, with a small percentage experiencing long-term pain and neurological symptoms. Studies are needed to determine best practices for regional anesthesia and functional assessments in this patient population.

[Comparison of the early analgesic efficacy of three different drugs after anterior cruciate ligament reconstruction].

OBJECTIVE: The pain-relieving effect and safety of compound aminopyrine phenacetin tablets, tramcontin (tramadol hydrochloride sustained-release tablets) and dolantin in the early stage of autologous tendon reconstruction of the anterior cruciate ligament (ACL) of the knee joint were compared. METHODS: Retrospective analysis of postoperative pain and drug analgesia in 45 patients performed by the same group from November 2018 to February 2019. The random area group design was divided into two groups according to whether ACL rupture was combined with meniscal injury, group A was 24 patients with ACL reconstruction of knee joint and group B was 21 patients with ACL fracture combined with meniscus injury. The two groups were divided into three subgroups respectively according to the actual treatment of postoperative analgesic drugs received by the patients, including 4 cases of compound aminopyrine phenacetin tablets, 11 cases of oral tramcontin, 9 cases of intramuscular dolantin combined with phenergan in group A; 3 cases of compound aminopyrine phenacetin tablets, 10 cases of oral tramcontin, and 8 cases of intramuscular dolantin combined with phenergan in group B. When the early postoperative patients complain about pain and actively ask for analgesia. When the patients complained about pain after the operation and actively asked for analgesia, they were randomly given painkillers, tramcontin or dolantin combined with phenergan to relieve pain. Pain visual analogue scale (VAS) was used to evaluate pain relief and observe the occurrence of adverse reactions. RESULTS: There were no significant dif-ferences in gender, age, body mass index, and time of hospital stay between the two groups of patients (P > 0.05). In the patients who used tramcontin and dolantin combined with phenergan to relieve pain judging by VAS score before and 1 h after taking the drug, it was found that the pain situation of the patient was significantly relieved, and the difference before and after taking the drug had statistical significance (P < 0.05). Pairwise comparisons of the three drugs applied in the two groups showed significantly greater pain relief in the dolantin combined with phenergan group than in the remaining two drugs. There was no significant difference (P > 0.05). Dolantin was prone to nausea and vomiting, but the application of phenergan was also used to reduce side effects. In terms of adverse reactions, only 1 case of nausea occurred in the tramcontin group for simple ACL reconstruction, and none of the patients in the other groups showed serious complications and allergic reactions. CONCLUSION: Whether in cruciate ligament reconstruction alone or combined with meniscus molding or suture, compound aminopyrine phenacetin tablets, tramcontin, dolantin combined with phenergan can effectively relieve pain. Among the three drugs, dolantin caused the largest pain relief. At the same time, the combination of phenergan effectively reduced the adverse reactions, such as vomiting and nausea, and increased the drug safety.

Low-dose ketamine infusion to facilitate opioid tapering in chronic non-cancer pain with opioid-use disorder: a historical cohort study.

BACKGROUND: Long-term opioid use is associated with pharmacological tolerance, a risk of misuse and hyperalgesia in patients with chronic pain (CP). Tapering is challenging in this context, particularly with comorbid opioid-use disorder (OUD). The antihyperalgesic effect of ketamine, through N-methyl-D-aspartate (NMDA) antagonism, could be useful. We aimed to describe the changes in the dose of opioids consumed over 1 year after a 5-day hospitalisation with ketamine infusion for CP patients with OUD. METHODS: We performed a historical cohort study using a medical chart from 1 January 2014 to 31 December 2019. Patients were long-term opioid users with OUD and CP, followed by the Pain Center of the University Hospital of Toulouse, for which outpatient progressive tapering failed. Ketamine was administered at a low dose to initiate tapering during a 5-day hospitalisation. RESULTS: 59 patients were included, with 64% of them female and a mean age of 48±10 years old. The most frequent CP aetiologies were back pain (53%) and fibromyalgia (17%). The baseline opioid daily dose was 207 mg (±128) morphine milligram equivalent (MME). It was lowered to 92±72 mg MME at discharge (p<0.001), 99±77 mg at 3 months (p<0.001) and 103±106 mg at 12 months. More than 50% tapering was achieved immediately for 40 patients (68%), with immediate cessation for seven patients (12%). 17 patients were lost to follow-up. CONCLUSIONS: A 5-day hospitalisation with a low-dose ketamine infusion appeared useful to facilitate opioid tapering in long-term opioid users with CP and OUD. Ketamine was well tolerated, and patients did not present significant withdrawal symptoms. Prospective and comparative studies are needed to confirm our findings.

Intravenous versus oral acetaminophen for pain and quality of recovery after ambulatory spine surgery: a randomized controlled trial.

INTRODUCTION: As ambulatory spine surgery increases, efficient recovery and discharge become essential. Multimodal analgesia is superior to opioids alone. Acetaminophen is a central component of multimodal protocols and both intravenous and oral forms are used. While some advantages for intravenous acetaminophen have been touted, prospective studies with patient-centered outcomes are lacking in ambulatory spine surgery. A substantial cost difference exists. We hypothesized that intravenous acetaminophen would be associated with fewer opioids and better recovery. METHODS: Patients undergoing ambulatory spine surgery were randomized to preoperative oral placebo and intraoperative intravenous acetaminophen or preoperative oral acetaminophen. All patients received general anesthesia and multimodal analgesia. The primary outcome was 24-hour opioid use in intravenous morphine milligram equivalents (MMEs), beginning with arrival to the postanesthesia care unit (PACU). Secondary outcomes included pain, Quality of Recovery (QoR)-15 scores, postoperative nausea and vomiting, recovery time, and correlations between pain catastrophizing, QoR-15, and pain. RESULTS: A total of 82 patients were included in final analyses. Demographics were similar between groups. For the primary outcome, the median 24-hour MMEs did not differ between groups (12.6 (4.0, 27.1) vs 12.0 (4.0, 29.5) mg, p=0.893). Postoperative pain ratings, PACU MMEs, QoR-15 scores, and recovery time showed no differences. Spearman's correlation showed a moderate negative correlation between postoperative opioid use and QoR-15. CONCLUSION: Intravenous acetaminophen was not superior to the oral form in ambulatory spine surgery patients. This does not support routine use of the more expensive intravenous form to improve recovery and accelerate discharge. TRIAL REGISTRATION NUMBER: NCT04574778.