Comparison of Ropivacaine and Levobupivacaine in High Thoracic Epidural Anesthesia

Study Overview
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Brief Summary
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In High Thoracic Epidural Anesthesia (HTEA) the use of a local anesthetic (LA) with low cardiac toxicity is crucial as myocardial contractility is often already seriously impaired. The aim of this study is to compare the efficacy, doses and side effects of ropivacaine and levobupivacaine in patients submitted to coronary artery bypass graft with HTEA and general anesthesia. The primary end point is the amount of LA drug required to maintain a VAS < 4 when coughing in the first 24 postoperative hours.

Detailed Description
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The use of high thoracic epidural, combined with general anesthesia (HTEA) in patients undergoing cardiac surgery has become increasing popular in recent years. In fact, this technique is potentially beneficial because of the attenuation of the stress response to surgery, the sympathetic tone reduction and the excellent postoperative analgesia.Patients submitted to coronary artery bypass graft will be randomly allocated to receive high epidural block with ropivacaine (R) or levobupivacaine (L), supplemented with sufentanil, during and after surgery. Postoperatively, the rate of epidural infusion will be modified to maintain a VAS score less than 4 in the thoracic area when coughing. VAS, total amount and rate of epidural drug infusion, MAP, total amount and rate of norepinephrine infusion and motor block will be recorded on arrival in the ICU, on awakening and after 4, 8, 12, 24 hours. Additionally, the onset time of the epidural sensory block, the time of awakening and the time on ventilator will be recorded as well as episodes of postoperative nausea and vomiting (PONV) and pruritus.

Official Title
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High Thoracic Epidural Anesthesia and Postoperative Analgesia With Ropivacaine or Levobupivacaine for Coronary Surgery: A Prospective Randomized Double-Blind Comparison

Conditions
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Epidural Anesthesia, Coronary Artery Bypass

Intervention / Treatment
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* Drug: Ropivacaine
* Drug: Levobupivacaine


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients scheduled for coronary artery bypass grafting with stable angina left ventricular ejection fraction > 30% age > 18 years having signed a written informed consent. Prothrombin Time (PT) > 80% and Partial Thromboplastin Time (PTT) within the normal range, and platelet counts (PLT) > 100.000 /mL Exclusion Criteria: emergency operation known coagulation disorders or recent thrombolytic therapy angina on arrival in the operating room acute myocardial infarction within the previous seven days clinically significant associated valvular disease known neuraxial pathology patients participating in other clinical research protocols.

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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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: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: R<br> | Drug: Ropivacaine<br>* 0.5% epidural bolus injection (0.1 mL kg-1) with sufentanil 2.5 µg mL-1 before general anesthesia induction, followed by 0.2% infusion (0.1 mL kg-1 h-1) with sufentanil 1 µg mL-1 throughout surgery; in ICU, 0.1% epidural infusion with sufentanil 1µg mL-1 at 0.1 mL kg-1 h-1 and the rate is modified following this protocol: on awakening (Ramsay 2) VAS on coughing is evaluated: if it is 4 the infusion rate is not changed, if the VAS is ≥ 4 the rate is increased by 2 mL h-1 after giving a 2 mL bolus and VAS is checked again 30 minutes later, if it is ≤ 4 the infusion rate is decreased by 2 mL h-1.<br>* Other names: Naropina;|
| Active Comparator: L<br> | Drug: Levobupivacaine<br>* 0.5% epidural bolus injection (0.1 mL kg-1) with sufentanil 2.5 µg mL-1 before general anesthesia induction, followed by 0.2% infusion (0.1 mL kg-1 h-1) with sufentanil 1 µg mL-1 throughout surgery; in ICU, 0.1% epidural infusion with sufentanil 1µg mL-1 at 0.1 mL kg-1 h-1 and the rate is modified following this protocol: on awakening (Ramsay 2) VAS on coughing is evaluated: if it is 4 the infusion rate is not changed, if the VAS is ≥ 4 the rate is increased by 2 mL h-1 after giving a 2 mL bolus and VAS is checked again 30 minutes later, if it is ≤ 4 the infusion rate is decreased by 2 mL h-1.<br>* Other names: Chirocaina;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The amount of local anesthetic drug (mg) required to maintain a visual analog scale score for pain (VAS) < 4 when coughing. |  | the first 24 postoperative hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| - The onset time of a T1-T6 block after the bolus. - the amount of norepinephrine needed to maintain MAP > 70. - differences in motor block. - side effects. |  | The first 24 postoperative hours |