Duloxetine As an Analgesic in Patients Without Central Sensitivity After Same Sitting Bilateral Total Knee Arthroplasty

Duloxetine As an Analgesic in Patients Without Central Sensitivity Undergoing Single-sitting, Bilateral Total Knee Arthroplasty: a Prospective, Double-blinded, Randomised, Placebo-controlled Trial

Analgesic effect of 20mg Duloxetine was evaluated at regular short term intervals in patients without central sensitivity and undergoing bilateral single sitting total knee arthroplasty for tricompartmental osteoarthritis using standardised patient related outcome measures like the visual analogue score.

Patients who underwent bilateral, single-sitting total knee arthroplasty for tricompartmental knee osteoarthritis were evaluated preoperatively for having central sensitivity. Only patients without central sensitisation were recruited and randomised into two groups with one group given 20 mg duloxetine capsules and the other group given a starch capsule of same shape, make, and weight as a placebo. Patients were evaluated for pain at rest and movement using VAS. A 6-hourly calculation of VAS was done over the first 48 hours and the average was recorded. Subsequent measurements at 1 week, 2 weeks, 4 weeks, and 3 months after surgery was done by a blinded clinician. Additional, drug safety, NSAID consumption and overall patient satisfaction were studied.

Inclusion Criteria:

• Bilateral tricompartmental knee osteoarthritis
• Underwent primary, bilateral TKA in single-sitting

Exclusion Criteria:

• American Society of Anesthesiologists physical status IV
• Hamilton Depression Scale (HAMD) and/or Hamilton Anxiety Scale (HAMA) scores > 7
• known intolerance or allergy to any of the study drugs, alcohol, tobacco, narcotic, or opioid dependence
• patients on anticoagulants
• known hepatic/renal dysfunction
• serious cardiac/cerebrovascular comorbidities
• HbA1c≥7
• patients who were already on duloxetine or other SNRIs, monoamine oxidase inhibitors, tricyclic antidepressants, triptans, lithium, other antiepileptics, or buspirone.