Perioperative Administration of Gabapentin for Reducing Inhalational Anesthetic Consumption

Study Overview
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Brief Summary
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Gabapentin, a structural analog of gamma aminobutyric acid (GABA), was introduced within the us as an anticonvulsant, used clinically to treat epilepsy. The drug causes amino acids release within the medulla spinalis dorsal horn and thus decreasing response to neural inputs and stabilizing the nervous activity. The mechanism of action of gabapentin on neuropathic pain is assumed to bind to the alpha 2 delta subunit of the voltage-dependent calcium channel within the central systema nervosum , reducing calcium influx into the nerve terminals and decreases the release of neurotransmitters like glutamate . Gabapentin, therefore, can be used for controlling chronic pain, as in diabetic neuropathy and other neuropathic disorders . Some studies examined the effectiveness of gabapentin for acute postoperative pain management for gynecological surgery, lumbar spinal surgery, arthroplasty, and thoracic surgery . A recent study concluded that gabapentin has a role in preoperative anxiolysis, attenuation of hemodynamic response to intubation, prevention of postoperative nausea and vomiting (PONV) and finally postoperative delirium . Up to date, the effect of preoperative gabapentin on inhaled anesthetic depth is unknown

Official Title
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Perioperative Administration of Gabapentin for Reducing Inhalational Anesthetic Consumption

Conditions
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Gabapentin

Intervention / Treatment
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* Drug: oral gabapentin


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: Patients aged from 18 to 60 years. ASA I-II. Undergoing craniotomy for intracranial tumors. Exclusion criteria: Patient refusal Patients younger than 18 or above 60 years old patients with (ASA) physical status ≥ III patients with compromised cardiovascular, renal, hepatic or neurological function Known allergy to study drug. Contraindication or chronic use (consistent use for longer than 3 months) to any of the study drugs Suffered from severe psychiatric disease or drug addiction; History of parenteral or oral analgesic intake within the last 48hours

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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: group I<br>will be received oral gabapentin capsule 1200 mg 2h pre-operatively. | Drug: oral gabapentin<br>* will be received oral gabapentin capsule 2 HOURS pre-operatively.<br>|
| Active Comparator: group II<br>will be received oral gabapentin capsule 600 mg 2h pre-operatively. | Drug: oral gabapentin<br>* will be received oral gabapentin capsule 2 HOURS pre-operatively.<br>|
| No Intervention: Group III<br>will be received placebo capsules at 2 hours preoperatively. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| sevoflurane consumption | Intra-operative consumption of sevoflurane will be measured and recorded (ml/hr). | 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| nalbuphine consumption | postoperative nalbuphine consumption by mg | 24 hours | 
| Intraoperative fentanyl consumption. | Intraoperative fentanyl consumption by mic | 6 hours |