Dose-response of Ketamine in Patient Controlled Analgesia in Orthopaedic Surgery Patients

Study Overview
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Brief Summary
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To study the multimodal protocol combining adjunct ketamine with oxycodone in intravenous patient-controlled analgesia bolus dosing and effects in patients scheduled for posterolateral lumbar spine fusion with bilateral transpedicular screw instrumentation

Official Title
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Dose Response Study of Patient Controlled Analgesia (PCA) of S-ketamine in Orthopaedic Spine Surgery Patients

Conditions
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Pain, Postoperative

Intervention / Treatment
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* Drug: Oxycodone
* Drug: S-Ketamine 0.25
* Drug: S-Ketamine 0.5
* Drug: S-Ketamine 0.75


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 20 - 75 years of age Scheduled for elective posterolateral lumbar spine fusion with bilateral transpedicular screw instrumentation under general anaesthesia. Written informed consent from the participating patient Exclusion Criteria: A previous history of intolerance to the study drug or related compounds and additives Concomitant drug therapy with opioids or strong CYP3A4 or CYP2B6 inductor(s) or inhibitor(s) 2 weeks prior to study. Patients younger than 20 years and older than 75 years. BMI > 35, sleep apnoea, any other sleep disorder or condition that requires treatment with continuous positive airway pressure or automatic positive airway pressure device. Existing significant liver or kidney disease History of ischemic heart disease or conduction disturbance History of alcoholism, drug abuse, psychological or other emotional problems that are likely to invalidate informed consent Donation of blood for 4 weeks prior and during the study.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 75 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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Placebo<br>Oxycodone 1 mg / ml alone | Drug: Oxycodone<br>* Current clinical practice, used as a control in this study<br>* Other names: Oxanest;|
| Active Comparator: Ketamine 0.25<br>Oxycodone 1 mg / ml + S-ketamine 0.25 mg / ml (ratio 1:0.25) | Drug: S-Ketamine 0.25<br>* dosage<br>* Other names: Ketanest-S;|
| Active Comparator: Ketamine 0.5<br>Oxycodone 1 mg / ml + S-ketamine 0.5 mg / ml (ratio 1:0.5) | Drug: S-Ketamine 0.5<br>* dosage<br>* Other names: Ketanest-S;|
| Active Comparator: Ketamine 0.75<br>Oxycodone 1 mg / ml + S-ketamine 0.75 mg / ml (ratio 1:0.75) | Drug: S-Ketamine 0.75<br>* dosage<br>* Other names: Ketanest-S;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in opioid consumption (mg) postoperatively | Change from baseline opioid consumption (mg) postoperatively at 24 and 72 hours | 24 and 72 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in numerical rating scale (NRS 0-10) | Change from baseline NRS value postoperatively at 24 and 72 hours | 24 and 72 hours |