Intraoperative Methadone for the Prevention of Postoperative Pain

Study Overview
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Brief Summary
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The pain felt after orthopedic surgery in the absence of adequate locoregional anesthesia is often insufficiently controlled, especially during the first 24 hours postoperatively. Methadone, due to its long half-life, may provide better pain control after orthopedic surgery when associated locoregional anesthesia cannot be performed. It may be impossible to perform loco-regional anesthesia in various contexts: patient refusal, pre-existing neurological impairment, infection at the injection site, coagulopathies, inability to cooperate, total language barrier, allergy to anesthetics, unavailability of equipment (ultrasound, etc.) or equipped room, lack of experience of nursing staff in performing the block and in the postoperative management of the patient. Intraoperative administration of methadone in these settings may be superior to sufentanil for pain control during the 24 hours post orthopedic surgery, and the pain control provided by methadone does not appear to imply a higher likelihood of adverse events related to opioids.

Official Title
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Intraoperative Methadone for the Prevention of Postoperative Pain: a Randomized, Double-blind Clinical Study in Orthopedic Surgery

Conditions
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Orthopedic Surgery

Intervention / Treatment
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* Drug: Methadone Hydrochloride
* Drug: Sufentanil Citrate


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age between 18 and 80 years old ASA 1-3 status Elective partial or total hip and knee arthroplasty Exclusion Criteria: Patient refusal Preoperative renal failure (serum creatinine > 2 mg/dL or 1.5-fold Increase in basal plasma creatinine or GFR < 90 ml/min/1.73m2) Significant hepatic dysfunction (PT <50% or increase in 3 times basal transaminases) Known heart failure Preoperative hemodynamic instability (preoperative use of inotropes or vasopressors) Known methadone or sufentanil allergy Preoperative opioid use or history of opioid abuse Pregnancy and breastfeeding.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: S Group<br>Patients receiving sufentanil during induction of general anesthesia | Drug: Sufentanil Citrate<br>* Classic induction of anesthesia (opioid, hypnotic and curare) but the team is blinded to the opioid used (sufentanil or methadone), which is prepared in identical syringes by the pharmacy<br>|
| Experimental: M Group<br>Patients receiving methadone during induction of general anesthesia | Drug: Methadone Hydrochloride<br>* Classic induction of anesthesia (opioid, hypnotic and curare) but the team is blinded to the opioid used (sufentanil or methadone), which is prepared in identical syringes by the pharmacy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Total morphine consumption | Total morphine consumption | 72 hours | 
| Standard visual analogue scale (VAS) | Pain is assessed using a standard visual analogue scale (VAS) in 11 points (from 0 (no pain) to 10 (worst pain)) | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Patient satisfaction | Patient satisfaction is assessed by means of a questionnaire at the end of hospital stay | 72 hours |