Ideal Initial Bolus and Infusion Rate for Erector Spinae Plane Block Catheters

Study Overview
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Brief Summary
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This study would like to identify the best starting dose and infusion rate for nerve blocks and nerve catheters related to the erector spinae plane block that can improve functional status and pain control on cardiac surgery patients and minimize the necessity for opioid pain control using a continuous reassessment model.

Detailed Description
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The study will continue taking steps in helping to identify the role erector spinae plane nerve blocks have in thoracic surgery. This is a relatively new nerve block (first identified and described in 2016) and the studies that have been done and the case series that have been reported have been very promising in supporting its role in thoracic surgery. As it is a plane block (not around a specific nerve but in a general area), larger volumes and doses often have to be used in these sorts of blocks (such as a transverses abdominalis plane block) to get good spread of the local anesthetic in the plane to reach the desired nerves that pass through this plane with one injection. Our hospital has been doing these blocks for patients as a standard of care for them, but this study will take a closer look to see if there is an optimal dose and volume of medicine to improve patients' functional status and pain control to minimize the need for opioids. The study will use a continuous reassessment model to determine the optimal dose.

Official Title
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Ideal Initial Bolus and Infusion Rate for Erector Spinae Plane Block Catheters

Conditions
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Pain, Postoperative, Pain, Chest

Intervention / Treatment
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* Drug: Ropivacaine 0.2%-Sodium Chloride 0.9% Injectable Solution bilaterally
* Drug: Ropivacaine 0.2%-Sodium Chloride 0.9% Injectable Solution unilaterally


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients undergoing planned thoracotomies and sternotomies for cardiothoracic surgery who will be taken to the cardiac surgery ICU postoperatively Exclusion Criteria: BMI >40 infection at the proposed catheter site ongoing sepsis/bacteremia patient unable to sit up for the procedure patients requiring significant vasopressor support (>1 vasopressor) patient refusal less than 18 years of age (they are managed in the pediatric ICU rather than the Cardiac Surgery ICU)

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: Supportive Care
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Bilateral catheters<br>patients receiving bilateral catheters (such as for patients undergoing sternotomies/midline incisions or with planned bilateral thoracotomy incisions) | Drug: Ropivacaine 0.2%-Sodium Chloride 0.9% Injectable Solution bilaterally<br>* Variable initial post-operative dose of 10cc to 40cc bilaterally with a variable programmed dose to be repeated afterward of 10cc to 40cc of 0.2% ropivacaine every 6 hours bilaterally.<br>|
| Experimental: Single catheter<br>patients who only have one catheter in place (such as in patients who have unilateral thoracotomies and not midline sternotomies) | Drug: Ropivacaine 0.2%-Sodium Chloride 0.9% Injectable Solution unilaterally<br>* Variable initial post-operative dose of 10cc to 40cc unilaterally with a variable programmed dose to be repeated afterward of 10cc to 40cc of 0.2% ropivacaine every 6 hours unilaterally.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Median Effective Dose | Dose at which 50% of patients achieve a clinically significant nerve block after a single bolus and after periodic programmed boluses of Ropivacaine as represented by either an adequate decrease in sensation of the chest (covering at least 5 dermatomes) or an improvement in vital capacity breaths (of 500 mL or more) | 6.5 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in pain rating | Self reported pain rating on a 0-10 scale where 0 is no pain and 10 is pain as bad as it can be | From just before to 30 minutes after a bolus is administered | 
| Change in heart rate | Heart rate measured using a heart rate monitor | From just before to 30 minutes after a bolus is administered | 
| Blood pressure | Blood pressure measured using a blood pressure monitor | From just before to 30 minutes after a bolus is administered | 
| Change in percent oxygen saturation of hemoglobin | Pulse oximetry reading from a monitor | From just before to 30 minutes after a bolus is administered | 
| Changes in electrocardiogram tracing | Monitoring for changes in electrical conduction in the heart as monitored by the continuous 5 lead electrocardiogram tracing, watching for any side effects. | From just before a bolus is administered to 6.5 hours | 
| Dermatomal coverage | The area of numbness experienced in the chest wall as measured using a pinprick test and documented on a cartoon map showing a chest wall and dermatomal borders | From just before to 30 minutes after a bolus is administered | 
| Opioid consumption | Total opioid medication consumption during the study period | 6.5 hours | 
| Non-narcotic pain medication consumption | Total non-narcotic pain medicine consumption during the study period | 6.5 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Erector Spinae, Cardiac Surgery, Regional Anesthesia