Analgesic Efficacy of Pre-operative Oral Pregabalin in Dacryocystorhinostomy Surgery

Study Overview
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Brief Summary
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This study is conducted to evaluate the effects of preoperative oral pregabalin on postoperative pain and analgesic requirements in patients undergoing DCR surgery. The primary outcome is to compare pain scores by visual analogue scale (VAS). Secondary outcomes are the time of first analgesic request, the total analgesic requirements during the postoperative 24 hours, the incidence of PONV, in addition to effect on hemodynamic parameters between the two groups.

Detailed Description
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External dacryocystorhinostomy (DCR) is still considered the golden standard for lacrimal surgery. It is a bypass technique which creates an anastomosis between the lacrimal sac and the nasal mucosa through a bony ostium via an external skin incision. External DCR can be completed under either local or general anesthesia. It is a painful surgical procedure that involves intra- and extra-ocular dissection, with a high prevalence post-operative nausea and vomiting (PONV). So, it is necessary to ensure a stress-free peri-operative period with adequate pain relief and a low incidence of PONV after DCR surgery. Pregabalin is a lipophilic gamma-amino-butyric acid (GABA) analogue that binds to the voltage-gated calcium channels. It reduces the excitability of the dorsal horn neurons after tissue damage. It has anticonvulsant, anxiolytic and sleep-modulating properties. It was shown to be effective in several models of neuropathic pain, incisional injury, and inflammatory injury. Preoperative administration of pregabalin is supposed to be a promising technique of enhancing postoperative pain control and reduction in postoperative opioid consumption. This study is a prospective randomized double-blind clinical trial included 100 ASA I and II patients of both sex with age between 18 and 65 years old, who are planned for elective DCR surgery under general anesthesia in Mansoura University ophthalmology center. Informed written consent is obtained from all subjects in the study after ensuring confidentiality. Details of the anesthetic technique and the study protocol are clarified to the entire involved cases. Patients are randomly assigned to two equal groups according to computer-generated randomization schedule. A prospective analysis of the collected data is performed using the Statistical Package for the Social Sciences (SPSS) program for Windows (version 22). All data are considered statistically significant if P value is ≤ 0.05.

Official Title
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Analgesic Efficacy of Pre-operative Oral Pregabalin in Dacryocystorhinostomy Surgery

Conditions
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Dacryocystitis

Intervention / Treatment
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* Drug: Pregabalin 150mg
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: American Society of Anesthesiology (ASA) I and II patients. Scheduled for DCR surgery. Exclusion Criteria: Patient' refusal of consent. Mental, psychological or neurological disorders. Patients with history of drug or alcohol abuse. History of know sensitivity to the used drugs. Bleeding or coagulation diathesis. Obese patients (body mass index (BMI) < 35). Pregnancy and lactation.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 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 |
| --- | --- |
| Active Comparator: Pregabalin Group<br>Patients received two capsules: one at the night of surgery, and the other at 2 hours before the surgery | Drug: Pregabalin 150mg<br>* Two capsules of pregabalin is administered orally to patients<br>* Other names: Lyrica;|
| Placebo Comparator: Control Group<br>Patients received two capsules: one at the night of surgery, and the other at 2 hours before the surgery | Drug: Placebo<br>* Two identical placebo capsules is administered orally to patients<br>* Other names: Control;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in pain scores by visual analogue scale (VAS) | Pain (VAS) score from 0 to 10 (0 = no pain and 10 = the worst imaginable pain) | Up to 24 hours after the procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in heart rate | Heart rate (beat/min) is recorded at five-minute intervals until the end of the surgery | Up to the end of the surgery | 
| Changes in mean arterial blood pressure | Blood pressure (mmHg) is recorded at five-minute intervals until the end of the surgery | Up to the end of the surgery | 
| First analgesic request | The time of the first analgesic request for pethidine is recorded. | Up to 24 hours after the procedure | 
| Total analgesic requirements of pethidine | The amount of pethidine consumption given as a rescue analgesia to patients is measured all over the 24 hours. | Up to 24 hours after the procedure | 
| Incidence of postoperative nausea and vomiting | Incidence of postoperative nausea and vomiting is assessed up to 24 hours after the procedure | Up to 24 hours after the procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pregabalin, Dacryocystorhinostomy, Analgesia