Continuous Interscalene Block vs Liposomal Bupivacaine After Proximal Humerus Fracture Surgery

Study Overview
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Brief Summary
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The purpose of this study is to compare the efficacy of continuous interscalene block (CISB) using standard bupivacaine versus a single interscalene injection of liposomal bupivacaine (LB) on pain control following surgical fixation of proximal humerus fractures.

Detailed Description
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Restricted range of motion following open reduction and internal fixation (ORIF) of proximal humerus fractures is a potential complication that severely limits functional outcomes . It must therefore be avoided by adequate pain control in order to allow for early mobilisation in addition to physiotherapy. Interscalene block (ISB) is one of the most effective and widely used regional analgesic options shoulder surgeries. ISB can be delivered as a single injection or by continuous infusion via an indwelling catheter. While continuous interscalene block (CISB) offers a longer duration of analgesia as compared to a single injection of the same anaesthetic, it carries an inherent risk of catheter malposition, dislodgement, and infection. As compared to standard bupivacaine (SB), liposomal bupivacaine (LB) is a formulation designed to prolong the duration of analgesia up to 72 hours via a single injection. While this could avoid the need for an indwelling catheter, results of studies comparing LB to CISB have been inconsistent. The purpose of this is non-inferiority trial is to compare the effectiveness of a single injection of LB versus CISB with SB on pain control following ORIF of proximal humerus fractures. The study hypothesis is that LB is not unacceptably worse than CISB with regard to pain control in the first two postoperative days. Patients providing informed consent will be screened for eligibility. All eligible patients will be randomly assigned in a double-blind manner (participant and investigator) and a 1:1 ratio to receive either LB or CISB.

Official Title
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Continuous Standard Bupivacaine Interscalene Block Versus Single Injection Liposomal Bupivacaine Following Surgical Fixation of Proximal Humerus Fractures

Conditions
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Shoulder Fractures

Intervention / Treatment
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* Drug: Liposomal bupivacaine
* Drug: Standard bupivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: ASA I-III Age between 18 and 80 Isolated Proximal humeral fracture (AO Types 31.A1-3 and B1-3 or Neer 2/3 part or greater tuberosity fracture equivalent) Locking Plate fixation Split deltoid minimal invasive approach Exclusion Criteria: Revision surgery Impaired cognitive function (Abbreviated Mental Test Score (AMT score) < 8) 4 part fractures Poor surgical reduction quality Unable to attend rehabilitation Preexisting shoulder problems Fracture fixation stability unable to tolerate early passive motion exercise Use of implants other than a locking plate for fracture fixation Activity of daily living is dependent on others Polytrauma Use of deltopectoral approach Patient unable to follow post-operative rehabilitation protocol with early mobilization Allergy to amide local anaesthetics, paracetamol, non-steroidal anti-inflammatory drugs (NSAIDS), opioids Respiratory Disease with limited respiratory reserve Cardiac Disease: Any degree of Heart Block, Heart Failure Neurological: Any Seizure Disorder Psychiatric illnesses affecting pain perception e.g. severe depression and anxiety disorder Alcohol or substance abuse Chronic Pain, other than chronic knee pain Daily use of strong opioids (morphine, fentanyl, hydromorphone, ketobemidone, methadone, nicomorphine, oxycodone, or meperidine) Impaired Renal Function (defined as preoperative eGFR < 30ml /min /1.73 m2) Impaired Hepatic Function Pregnancy Inability to use PCA Patient refusal to ISB Patient refusal to study Patients do not understand Cantonese

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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
Interventional Model Description: Patients will be allocated to receive either continuous interscalene nerve block (CISB) using standard bupivacaine OR a single interscalene injection of liposomal bupivacaine (LB).
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Liposomal bupivacaine<br>Patients will receive a single bolus interscalene injection of 10mL 1.33% LB followed by placement of indwelling (sham) catheter in the interscalene region. Upon arrival in the recovery room, a nurse will connect the catheter to a fixed-rate portable elastometric pump (Easypump®, B Braun, Germany) filled with 300mL normal saline (NS) at a default fixed rate of infusion of 5mL/hr. The syringe, catheter, pump and clamp will be covered by opaque black bags to conceal the milky appearance of LB. The catheter will be removed on postoperative day 2. | Drug: Liposomal bupivacaine<br>* Single bolus injection 10mL 1.33% LB<br>* Other names: Exparel;|
| Active Comparator: Standard bupivacaine CISB<br>Patients will receive a single bolus interscalene injection of 10mL 0.25% SB followed by placement of indwelling (sham) catheter in the interscalene region. Upon arrival in the recovery room, a nurse will connect the catheter to a fixed-rate portable elastometric pump (Easypump®, B Braun, Germany) filled with 300mL 0.2% SB at a default fixed rate of infusion of 5mL/hr. The syringe, catheter, pump and clamp will be covered by opaque black bags to conceal the drug appearance. The catheter will be removed on postoperative day 2. | Drug: Standard bupivacaine<br>* Single bolus 10mL 0.25% SB + continuous 300mL 0.2% SB @5mL/hr<br>* Other names: Sensorcaine;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain on movement as measured by Numerical Rating Scale (NRS) | Numerical rating scale (NRS) during attempted passive forward shoulder flexion to 90 degrees; 0 points (no pain) to 11 points (worst pain imaginable). | At each post-op day 1-7 | 
| Pain at rest as measured by Numerical Rating Scale (NRS) | Numerical rating scale (NRS) at rest; 0 points (no pain) to 11 points (worst pain imaginable). | At each post-op day 1-7 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intraoperative opioid consumption | Intraoperative IV remifentanil consumption (mcg/kg/min) | Intraoperative | 
| Incidence of ISB related complications | Complications related to interscalene block | Intraoperative to post-op day 3 | 
| PCA morphine consumption | Amount of patient-controlled analgesia (PCA) morphine consumed (mg) | From immediately post-operation to post-op day 2 | 
| Number of patients with side effects effects of PCA using morphine | Side effects related to opioid use (Nausea/Vomiting, Dizziness, Constipation) | From immediately post-operation to post-op day 2 | 
| Rescue morphine consumption | Additional opioid used in addition to PCA morphine | From immediately post-operation to post-op day 2 | 
| Total length of stay | Duration of hospital stay (days) | Through study completion, an average of 1 year | 
| Analgesic consumption after discharge | Total analgesic consumption (dihydrocodeine) after hospital discharge (pill count) | From post-op day 3 to day 7 | 
| Overall Benefit of Analgesia Score (OBAS) | Patient-reported measure of pain, side effects, and satisfaction of post-operative analgesia; 7 questions rated from 0 (worst outcome) to 4 (best outcome) | Immediate post-operation to post-op day 3 | 
| Presence of chronic pain at follow-up | Presence of chronic pain by self-report | At 2 weeks, 6 weeks and 3 months post-op | 
| Presence of neuropathic pain at follow-up | Presence of neuropathic pain by physical examination and neuropathic pain questionnaire, a 10-item mixed self-report/observer rated physical exam measure ranging from 0 (no pain) to 10, with a score of 4 or greater diagnostic of neuropathic pain | At post-op 2 weeks, 6 weeks and 3 months | 
| Region-specific physical functioning and symptoms | Physical function and symptoms measured by Shortened Disabilities of the Arm, Shoulder and Hand Questionnaire (QuickDASH), an 11-item patient-reported measure with a total score ranging from 0 (no disability) to 100 (most severe disability). | At post-op 2 weeks, 6 weeks and 3 months | 
| Health-related quality of life (HRQOL) | 12-item Short Form Health Survey (SF-12), a patient-reported outcome measure of HRQOL comprised of a mental component (MCS) and physical component (PCS), each with a final score ranging from 0 (worst outcome) to 100 (best outcome). | At post-op 2 weeks, 6 weeks and 3 months | 
| Patient satisfaction as measured by the Patient Satisfaction Questionnaire General Satisfaction Subscale | Patient satisfaction with healthcare provision as measured by the Patient Satisfaction Questionnaire General Satisfaction subscale (PSQ18-GS), a two-item subscale with a final score ranging from 0 (lowest satisfaction) to 10 (highest satisfaction) | At post-op 2 weeks, 6 weeks and 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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interscalene nerve block, shoulder surgery