Impact of Peripheral Nerve Blockade on Outcomes After Total Knee Replacement

Study Overview
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Brief Summary
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Pain is common after knee replacement surgery and can impact a variety of patient outcomes. Peripheral nerve blocks provide improved pain control and may improve function. However, their impact on other outcomes is poorly described. Therefore, this comparative effectiveness study will estimate the independent association between nerve blocks and health outcomes after knee replacement surgery.

Detailed Description
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This retrospective, population-based cohort study will evaluate the comparative effectiveness of peripheral nerve blocks on patient and health system outcomes after elective total knee replacement surgery. The investigators will develop a non-parsimonious propensity score to control for potential indication bias and confounding in this observational study. Using the propensity score the investigators will match patients who receive a peripheral nerve block to a patient who did not to estimate the independent association of peripheral nerve blocks with our study outcomes.

Official Title
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Impact of Peripheral Nerve Blockade on Outcomes After Total Knee Replacement

Conditions
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Pain, Osteoarthritis

Intervention / Treatment
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* Other: Peripheral nerve block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: first primary total knee replacement during the study period Exclusion Criteria: Revision arthroplasty

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Peripheral nerve block<br>Intervention arm. Participants who receive a peripheral nerve block identified through submission of an appropriate physician billing code | Other: Peripheral nerve block<br>* A physician billing code for deposition of a local anesthetic solution around an anatomically defined nerve or nerve plexus<br>|
| No peripheral nerve block<br>Control arm. Participants who do not receive a peripheral nerve block identified through lack of a submission of an appropriate physician billing code | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hospital length of stay | Determined from the Canadian Institute for Health Information Discharge Abstract Database record for the index hospitalization | Day of surgery to day of discharge, or up to 365 days, whichever comes first | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hospital readmission | Determined from the Canadian Institute for Health Information Discharge Abstract Database through identification of a new record after discharge from the index hospitalization | The outcome ascertainment window starts on the day of discharge and extends up to 30 days after surgery. Any readmission in this time period will be considered an event. | 
| In-hospital fall | Determined using validated International Classification of Diseases Tenth edition codes for falls from the index hospitalization Discharge Abstract Database record | hospital admission | 
| Emergency department visit | Defined as the creation of a record in the National Ambulatory Care Reporting System for an emergency department visit that occurs after discharge and before 30 days after discharge | The outcome ascertainment window starts on the day of discharge and extends up to 30 days after surgery. Any emergency department visit in this time period will be considered an event. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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orthopedics, anesthesiology, nerve block, length of stay, Patient readmission