Effects of Perioperative Intravenous Dexamethasone on the Severity of Persistent Postsurgical Pain After Total Knee Arthroplasty : A Prospective, Randomized, Double-blind, Placebo-controlled Trial

Study Overview
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Brief Summary
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To compare the effects of perioperative intravenous Dexamethasone with a placebo on the severity of persistent postsurgical pain after total knee arthroplasty.

Detailed Description
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It is not clear whether perioperative intravenous Dexamethasone has an effect on severity of persistent postsurgical pain (PPSP) after total knee arthroplasty (TKA). The research hypothesis is that TKA patients experience less severe PPSP after administration of perioperative intravenous Dexamethasone.

Official Title
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Effects of Perioperative Intravenous Dexamethasone on the Severity of Persistent Postsurgical Pain After Total Knee Arthroplasty : A Prospective, Randomized, Double-blind, Placebo-controlled Trial

Conditions
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Osteoarthritis of the Knee

Intervention / Treatment
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* Drug: Dexamethasone
* Drug: Normal saline solution


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age > 40 years (45) Primary knee osteoarthritis diagnosed using the American College of Rheumatology criteria (46) Undergoing elective, primary and unilateral total knee arthroplasty American Society of Anesthesiology (ASA) physical status class 1-3 BMI < 40 kg/m2 Exclusion Criteria: History of active rheumatic diseases History of previous musculoskeletal injury of the same knee for excluding patients with secondary knee osteoarthritis History of previous surgery on the same knee History of adverse effects from medications to be used in this study Contraindication to spinal anesthesia History of psychiatric disorders or cognitive impairment Contraindication to corticosteroid agents Poorly controlled diabetes mellitus (HbA1C > 7.5) Poorly controlled hypertension History of ischemic heart disease or peripheral arterial disease or cerebrovascular disease Hepatic insufficiency (Child-Pugh score > 5) Renal insufficiency (Creatinine clearance < 30 mL/min) History of cataracts or glaucoma or ocular hypertension History of steroid or immunosuppressive drug use within 6 months of surgery

Ages Eligible for Study
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Minimum Age: 40 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: Dexamethasone<br>The steroid group will receive Dexamethasone 10 mg IV immediately prior to induction of spinal anesthesia and will receive a second and third dose of Dexamethasone 10 mg IV postoperatively at 24 and 48 hrs. | Drug: Dexamethasone<br> <br> |
| Placebo Comparator: Placebo<br>The control group will receive sterile normal saline solution, serving as placebo, IV immediately prior to induction of spinal anesthesia and will receive a second and third dose of placebo IV postoperatively 24 and 48 hrs. Both Dexamethasone and normal saline solution will be administered as an IV push. | Drug: Normal saline solution<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Modified WOMAC scores for pain at 12 weeks postoperative | using the modified Thai version of the Western Ontario and McMaster (WOMAC) osteoarthritis index for knee osteoarthritis questionnaire | 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual analogue scales for pain during a five-meter walk (0-100) |  | postoperatively at 24, 30, 48, 54, 72 hrs | 
| Visual analogue scales for pain during 45 degree active knee flexion (0-100) |  | postoperatively at 6, 24, 30, 48, 54, 72 hrs | 
| Visual analogue scales for current pain at rest in a supine position (0-100) |  | postoperatively at 6, 24, 30, 48, 54, 72 hrs | 
| Visual analogue scales for maximum pain at rest over the last 24 hours and minimum pain at rest over the last 24 hours (0-100) |  | postoperatively at 0-24, 24-48, 48-72 hrs | 
| Visual analogue scale values for nausea (0-100) |  | postoperatively at 6, 24, 30, 48, 54, 72 hrs | 
| Opioid consumption (mg.) |  | during the first 0-24, 24-48, and 48-72 hrs | 
| Anti-emetic medicine consumption (mg.) |  | during the first 0-24, 24-48, and 48-72 hrs | 
| Maximum degree of active knee flexion |  | postoperatively at 24, 48, 72 hrs, 2 weeks, 6 weeks, and 12 weeks | 
| Modified WOMAC scores for pain | using the modified Thai version of the Western Ontario and McMaster (WOMAC) osteoarthritis index for knee osteoarthritis questionnaire | postoperatively at weeks 2 and 6 | 
| Wound complications |  | evaluated postoperatively at weeks 2, 6 and 12 |