A Dose Ranging Effect of Preoperative Diphenhydramine on Postoperative Quality of Recovery After Ambulatory Surgery

Study Overview
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Brief Summary
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Pain after ambulatory surgery remains an unsolved problem in The United States and Europe. It is associated with delayed hospital discharge and it can result to an increased opioid consumption with adverse side effects. The concept of multimodal analgesic technique was introduced more than 15 years ago and several techniques have been studied over the years including non steroidal antiinflammatory drugs (NSAIDs), acetaminophen, gabapentoids, ketamine, local and regional anesthetic techniques. Histamine can have effects on polymodal nociceptors and C-fibers, producing pain which is further increased by neurogenically mediated release of substance P from afferent pain fibers. Several non-selective or H1 -selective histamine receptors antagonists have been demonstrated in animal models and clinical pain. Chia et al demonstrated that preoperative promethazine had opioid sparing properties without adverse sedative effects in patients undergoing abdominal hysterectomy. Diphenhydramine is an anti-histamine drug who has been found to be effective in reducing postoperative nausea and vomiting after ambulatory surgery but its effects on postoperative pain and other important outcomes after ambulatory surgery such as time to meet discharge criteria have not being studied. The MQOR 40 is a validated instrument that was specifically design to evaluate patient recovery after anesthesia and surgery. This instrument can be particularly valid to examine interventions which affect different spheres of patient recovery as is the case of diphenhydramine. The objective of this study is to determine a dose response effect of preoperative diphenhydramine on postoperative quality of recovery after ambulatory surgery. The use of preoperative diphenhydramine can improve patient's quality of recovery, decrease postoperative pain, opioid consumption and opioid related side effects after ambulatory surgery. The research question: Does a preoperative dose of diphenhydramine improve postoperative quality of recovery after ambulatory surgery? The hypothesis of this study is that preoperative diphenhydramine will improve postoperative pain, Postoperative nausea and vomiting (PONV), sleep which will translate in a better overall quality of recovery.

Official Title
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A Dose Ranging Effect of Preoperative Diphenhydramine on Postoperative Quality of Recovery After Ambulatory Surgery

Conditions
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Surgery, Pain

Intervention / Treatment
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* Drug: .9 normal saline
* Drug: 25 mg diphenhydramine IV
* Drug: 50 mg diphenhydramine IV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18-64 years Patients undergoing ambulatory surgery ASA PS I, II. Exclusion Criteria: Chronic opioid use pregnant patient or lactating patients allergy to diphenhydramine glaucoma uncontrolled hypertension asthma hyperthyroidism cardiovascular disease

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 64 Years

Sexes Eligible for Study
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Female

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Placebo<br>.9 normal saline IV | Drug: .9 normal saline<br>* .9 normal saline administered before surgery.<br>|
| Active Comparator: 25 mg diphenhydramine IV<br>25 mg diphenhydramine IV administered before surgery | Drug: 25 mg diphenhydramine IV<br>* 25 mg diphenhydramine IV administered before surgery<br>|
| Active Comparator: 50 mg diphenhydramine IV<br>50 mg diphenhydramine IV administered before surgery | Drug: 50 mg diphenhydramine IV<br>* 50 mg diphenhydramine administered IV before surgery<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quality of Recovery 40 at 24 Hours | Scores on QOR (quality of recovery) 40 questionnaire.The QoR-40 score, which ranges from 40 to 200, representing very poor to outstanding quality of recovery, respectively. | 24 hours post operatively | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pain, anesthesia, surgery, postoperative