Parasternal Nerve Block in Cardiac Patients

Parasternal Intercostal Nerve Block in Post-Cardiac Surgery Patients: A Randomized, Controlled Trial of Extended-release Liposomal Bupivacaine (Exparel) Versus Placebo

Exparel is a new local analgesic (numbing medication) that is intended to be longer acting than currently available local analgesics. The purpose of this study is to determine whether use of Exparel to numb the nerves along the breastbone after open heart surgery, will decrease pain and pain medication use after surgery.

This is a Phase 2, single-institution, randomized, double-blind, parallel-group, placebo-controlled trial of patients undergoing a median sternotomy for primary cardiopulmonary bypass grafting (CABG) surgery.

78 subjects (39 per treatment arm) will be randomized in a 1:1 ratio to receive a single-dose, parasternal nerve block with either 266 mg Exparel or placebo (0.9% normal saline solution). The nerve blocks will be performed under direct visualization at the end of surgery, just prior to sternal closure.

Inclusion Criteria:

• ≥ 18 years old
• non-emergent coronary artery bypass grafting surgery (on and off pump)
• median sternotomy

Exclusion Criteria:

• Concomitant cardiac procedures (e.g. aortic valve repair/replacement, mitral valve repair/replacement, aortic root replacements).
• Redo sternotomy.
• < 50 kg (Exparel® is currently only approved in patients > 50 kg).
• Pregnant or nursing
• History of alcohol, narcotic or illicit drug abuse
• Participation in another study evaluating investigational medications within the past 30 days
• Taking narcotic analgesics within 3 days pre-operatively or perioperative stress-dose steroids.
• Chronic non-cardiac pain (e.g. lower back pain, fibromyalgia) requiring narcotic analgesics.
• Pre-operative mild liver insufficiency as defined by liver function tests [(i.e. alanine aminotransferase (ALT), aspartate aminotransferase (AST)] ≥ 1.5 times the upper limit of normal (ULN: ALT: 0-35 U/L, AST: 0-35 U/L, Alk Phos 35-105 U/L, Total bilirubin: 0-1.2 mg/dL)
• Pre-operative mild renal insufficiency (Cr ≥ 1.5 mg/dL)
• Allergy to amide-type anesthetics
• Recurrent ventricular arrhythmias, low cardiac output requiring inotrope and/or intra-aortic balloon pump support, left ventricular ejection fraction < 30% at time of pre-operative screening/evaluation.
• Unable to provide informed consent or unable to understand how to use pain rating scales.
• Inability to understand or operate the patient-controlled analgesia (PCA) machine.