Impact of Anesthesiology Interventions on Postoperative Outcomes in Adult Patients Undergoing Shoulder Surgery

Study Overview
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Brief Summary
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This retrospective, population-based cohort study will evaluate the comparative effectiveness of peripheral nerve blocks on patient outcomes after ambulatory shoulder surgery in adults patients undergoing surgery in Ontario.

Detailed Description
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First, investigators will validate health administrative data codes to demonstrate the accuracy of Ontario-wide anesthesia type and regional anesthesia interventions using a reference standard (Ottawa Hospital Data Warehouse data). Then, these validated exposures, in combination with validated outcome measures, will be used to examine the impact of anesthesia interventions on patient and health system outcomes for ambulatory shoulder surgery.

Official Title
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Impact of Anesthesiology Interventions on Postoperative Outcomes in Adult Patients Undergoing Ambulatory Shoulder Surgery

Conditions
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Postoperative Complications

Intervention / Treatment
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* Procedure: Isolated General Anesthesia
* Procedure: Peripheral Nerve Block


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Ontario residents Aged 18 years and older Elective ambulatory shoulder surgery performed in Ontario between April 2009 and December 2016. Exclusion Criteria: Emergency Surgery If a patient undergoes multiple elective shoulder surgeries within the time period, only the first surgery will be included for any participant in the study period.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Isolated General Anesthesia<br>Ontario residents, aged 18 years and older, who have undergone elective ambulatory shoulder surgery in Ontario and have not had a nerve block identified using physician billing codes. | Procedure: Isolated General Anesthesia<br>* No nerve block identified through physician billing codes<br>* Other names: iGA;|
| Peripheral Nerve Block<br>Ontario residents, aged 18 years and older, who have undergone elective ambulatory shoulder surgery in Ontario and have a nerve block identified using physician billing codes. | Procedure: Peripheral Nerve Block<br>* Nerve block identified through physician billing codes<br>* Other names: PNB+GA;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative death, admission, readmission or emergency department visits | Composite outcome of: 1) unplanned admissions on the day of surgery , 2) post-discharge emergency department visits within 7 days of surgery, 3) readmission within 7 days of surgery, and 4) death from any cause | Date of surgery to 7 days after surgery or death date, whichever came first | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Health system costs | Costs will be calculated using standardized patient-level costing algorithms. | Date of surgery to 7 days after surgery or death date, whichever came first | 
| Neurology consultations or diagnostics | Occurrence of neurology consult and/or nerve conduction study | Date of surgery to 90 days after surgery or death date, whichever came first |