The Use of Paravertebral Block for Cardiac Surgery

Study Overview
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Brief Summary
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Pain after robotic cardiac surgery is a known problem and is often difficult to manage. Paravertebral nerve blocks are a proven method of pain relief following thoracotomy. A paravertebral block has been shown to provide good pain relief with minimal side effects, however, paravertebral blocks for robotic surgery have not been well studied. Currently the investigators routinely perform PVB on this patient population (of 50 MV robotic cases done between January and October 2012, 36 received paravertebral blocks with no adverse events noted). The investigators believe this should be studied further and that paravertebral blocks will reduce the amount of additional pain medication patients require in the first 24 hours after surgery, decrease intubation time and improve PACU and hospital discharge times.

Detailed Description
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Pain after robotic cardiac surgery is a known problem and is often difficult to manage. Paravertebral nerve blocks are a proven method of pain relief following thoracotomy. A paravertebral block has been shown to provide good pain relief with minimal side effects, however, paravertebral blocks for robotic surgery have not been well studied. Currently we routinely perform PVB on this patient population (of 50 MV robotic cases done between January and October 2012, 36 received paravertebral blocks with no adverse events noted). We believe this should be studied further and that paravertebral blocks will reduce the amount of additional pain medication patients require in the first 24 hours after surgery, decrease intubation time and improve PACU and hospital discharge times.

Official Title
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Study of Paravertebral Block for Cardiac Surgery

Conditions
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Mitral Valve Insufficiency

Intervention / Treatment
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* Other: Paravertebral Block
* Other: Placebo Comparator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: patients over the age of 18 years of age undergoing robotic mitral valve surgery. have capacity to understand and sign consent form Exclusion Criteria: patients that are not candidates for paravertebral block as per ASRA guidelines (Horlocker, Reg Anesth Pain Med, 2010). In short, this includes patients taking specific anti platelet agents such as clopidigrel, anticoagulants such as heparin or low molecular weight heparin, or patients with an INR of greater than 1.5. -patients with a history of COPD or other respiratory diseases that would confound data on time to extubated will be excluded. Patients that with a diagnosis of chronic pain, or patients currently taking narcotics are excluded, as this would confound data on postoperative narcotic requirements.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 90 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: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Paravertebral block<br>Patient receiving a PVB prior to robotic mitral valve surgery | Other: Paravertebral Block<br>* Paravertebral nerve block injection<br>|
| Placebo Comparator: No block<br>Patients who did not receive PVB | Other: Placebo Comparator<br>* No block Patients who did not receive PVB<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Postoperative Fentanyl |  | 24 hours | 
| Visual Analog Scale (VAS) Pain Scores | Possible scores range from 0-10, with 0 being no pain and 10 being highest level of pain | 24 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Participant Satisfaction | Participants were asked whether or not they were satisfied with their postoperative pain control (yes or no) | 48 hours | 
| Participant Satisfaction Score | Participants were asked to score their satisfaction with their postoperative pain control on a scale of 0 (least satisfied) to 10 (most satisfied) | 48 hours |