Analgesic Efficacy of Duloxetine in Patients Undergoing Lumbar Discectomy

Study Overview
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Brief Summary
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Duloxetine is a serotonin-norepinephrine reuptake inhibitor primarily used for treatment of major depression and anxiety. Duloxetine also has been used in the treatment of chronic pain conditions, such as osteoarthritis and musculoskeletal pain. There are few studies examining its effect for acute pain. The objective of this study is to evaluate the analgesic effect of duloxetine for patients undergoing lumbar discectomy.

Official Title
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Analgesic Efficacy of Duloxetine in Patients Undergoing Lumbar Discectomy: Randomized Trial

Conditions
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Acute Pain

Intervention / Treatment
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* Drug: Duloxetine
* Drug: placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing lumbar discectomy Exclusion Criteria: Patients on regular opioid therapy Uncontrolled hypertensive patients Patients with ischemic heart disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: duloxitine group<br>Patients will receive single oral dose of duloxetine capsule, 60 mg, 2 hours before operation and will be anesthetized with general anesthesia that includes, Induction of anesthesia will be done by intravenous fentanyl, 2 µg / kg and propofol 1 - 2 mg / kg. Endotracheal intubation will be achieved by cis-atracurium, 0.15 mg / kg. Maintenance of anesthesia will be done by isoflurane and cis-atracurium, 0.03 mg / kg on demand. Additional intraoperative analgesia will be consisted of administration of intravenous boluses of fentanyl, 50 µg according to the attending anesthesiologist's decision. At the end of surgery, muscle relaxation was reversed using neostigmine 0.05 mg / kg and atropine 0.01 mg / kg. | Drug: Duloxetine<br>* The investigator will give the patients duloxetine capsule 60 mg orally before operation (skin incision) and anesthetize them with general anesthesia, then the investigator will test the postoperative analgesic efficacy in the form of 24 h analgesic consumption<br>|
| Placebo Comparator: placebo group<br>Patients will receive single oral dose of placebo capsule, 2 hours before operation and will be anesthetized with general anesthesia that includes, Induction of anesthesia will be done by intravenous fentanyl, 2 µg / kg and propofol 1 - 2 mg / kg. Endotracheal intubation will be achieved by cis-atracurium, 0.15 mg / kg. Maintenance of anesthesia will be done by isoflurane and cis-atracurium, 0.03 mg / kg on demand. Additional intraoperative analgesia will be consisted of administration of intravenous boluses of fentanyl, 50 µg according to the attending anesthesiologist's decision. At the end of surgery, muscle relaxation was reversed using neostigmine 0.05 mg / kg and atropine 0.01 mg / kg. | Drug: placebo<br>* Patients will receive single oral dose of placebo capsule, 2 hours before operation and will be anesthetized with general anesthesia that includes, Induction of anesthesia will be done by intravenous fentanyl, 2 µg / kg and propofol 1 - 2 mg / kg. Endotracheal intubation will be achieved by cis-atracurium, 0.15 mg / kg. Maintenance of anesthesia will be done by isoflurane and cis-atracurium, 0.03 mg / kg on demand. Additional intraoperative analgesia will be consisted of administration of intravenous boluses of fentanyl, 50 µg according to the attending anesthesiologist's decision. At the end of surgery, muscle relaxation was reversed using neostigmine 0.05 mg / kg and atropine 0.01 mg / kg<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| the first 24 hour morphine consumption | the first 24 hours cumulative morphine consumed by the patient via patient controlled analgesic device (PCA), set to deliver 2 mg morphine bolus with lockout interval 15 min, without background infusion | the first postoperative 24 hour |