Programmed Intermittent Bolus During Continuous Interscalene Nerve Block for Shoulder Arthroplasty

Study Overview
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Brief Summary
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A new infusion strategy named the 'programmed intermittent bolus' (PIB) technique delivers the hourly dose within minutes compared to the traditional infusion that delivers such dose over an hour. The PIB technique has demonstrated superior patient satisfaction and reduced local anesthetic consumption when utilized for pain control during labour and delivery. However, it is not known if the PIB technique gives any benefits during a continuous nerve block in other settings. The aim of this randomized controlled trial (RCT) is to elucidate if PIB is better than (traditional) continuous infusion for postoperative analgesia in patients receiving a continuous nerve block for total shoulder arthroplasty with respect to pain control.

Detailed Description
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Local anesthetics are often given in a continuous fashion to block specific nerves after an operation for pain control. A new infusion strategy named the 'programmed intermittent bolus' (PIB) technique delivers the hourly dose within minutes compared to the traditional infusion that delivers such dose over an hour. The PIB technique has demonstrated superior patient satisfaction and reduced local anesthetic consumption when utilized for pain control during labour and delivery. However, it is not known if the PIB technique gives any benefits during a continuous nerve block in other settings. The aim of this randomized controlled trial (RCT) is to elucidate if PIB is better than (traditional) continuous infusion for postoperative analgesia in patients receiving a continuous nerve block for total shoulder arthroplasty with respect to pain control.

Official Title
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Programmed Intermittent Bolus for Infusion of Local Anesthetic During Continuous Interscalene Nerve Blockade for Total Shoulder Arthroplasty: a Randomized Controlled Trial

Conditions
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Shoulder Arthroplasty, Shoulder Osteoarthritis, Pain Management

Intervention / Treatment
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* Device: Programmed Intermittent Bolus
* Device: Continuous Infusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients American Society of Anesthesiologists (ASA) Physical Status I to III Exclusion Criteria: Body mass index (BMI) > 40 Not able to communicate in ENglish Unable to obtain consent Infection over site of placement Severe respiratory disease Cognitive or psychiatric history that would make it difficult to assess pain score Complex regional pain syndrome Chronic pain condition such as fibromyalgia, neuropathic pain Preoperative opioid use greater than the equivalent of morphine 50 mg PO daily Allergy to any of the study drug Coagulopathy

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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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Quadruple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Programmed Intermittent Bolus (PIB)<br>For the experimental group, patients will receive 5 mL of the study solution as a bolus every hour via a PIB-capable infusion pump. | Device: Programmed Intermittent Bolus<br>* The Smith CADD(R)-Solis Ambulatory Infusion Pump will be used to provide programmed intermittent bolus for the interscalene block.<br>|
| Active Comparator: Continuous Infusion<br>The control (standard care) group will receive the study solution at a rate of 5mL/h continuously via the current infusion pump. | Device: Continuous Infusion<br>* The Smith CADD(R)-Solis Ambulatory Infusion Pump will be used to provide continuous infusion for the interscalene block.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain score on 11 point (0 - 10) numeric rating scale | Postoperative pain score | FIrst 24 hour since the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Local anesthetic consumption | The total dose of local anesthetic used until the block is discontinued | 36 hours (or until block discontinuation) | 
| Opioid consumption | The total amount of opioids consumed will be recorded until the patient is discharged | 48 hours (or until discharge) | 
| Side effect | nausea, voting, pruritus | through to patient discharge, on average 48 hours | 
| patient satisfaction | 100 mm visual analogue scale | through to patient discharge, on average 48 hours | 
| Block complication | persistent motor or sensory block, dyspnea, hoarseness, Horner syndrome | through to patient discharge, on average 48 hours |