Parasternal Subpectoral Plane Blocks for Cardiac Surgery Via a Midline Sternotomy

Parasternal Subpectoral Plane Blocks for Patients Undergoing Cardiac Surgery Involving Median Sternotomy - a Study of Opioid and Pain Reduction

To better determine whether parasternal subpectoral plane blocks (PSPB) infusing bupivacaine for midline sternotomy decreases opioid consumption and pain scores.

This is a prospective, blinded randomized controlled trial with 2 arms. 1 arm is the saline control arm, PSPB catheters will be placed with saline and continue to infuse saline. The other arm is bupivacaine study arm, PSPB catheters will be placed with bupivacaine and continue to infuse the local anesthetic.

Subjects will be randomized to receive PSPB catheters infusing either bupivacaine or saline. Randomization will be achieved using a computer-generated randomization scheme. The surgeon, nurse, anesthetist and patient will be blinded. The investigational drug service will prepare blinded solutions (bupivacaine 0.2% or saline syringes) for performance of the block. They will also prepare bags (either bupivacaine 0.125% or saline) to be infused through the catheter.

Following skin closure, but before removal of the surgical drapes, regional anesthesiologists will scrub in, gown and perform the placement of PSPB catheters under strict surgical aseptic technique. Real-time ultrasound (US) imaging will be used to visualize the pectoralis major muscle and its corresponding rib cartilages, and a needle/introducer sheath will be guided parasternally into the fascial plane. The needle will be advanced in the plane, hydro-dissecting with 30 mL of bupivacaine 0.2% in the study group or 30 mL of saline in the control group per side. Following hydro-dissection, a 5 in. multiport catheter will be inserted via the sheath, and the catheter will be secured following US confirmation of appropriate catheter position. This procedure will then be repeated on the other side. After completion of bilateral PSPB catheters, patients will remain intubated and be transferred to the CSICU on a sedation regimen at the discretion of the intraoperative anesthesia team. Upon dropping off to the ICU, each catheter will be attached to a programmable pump infusing plain bupivacaine 0.125% at 10 mL/hr or saline infusing at 10 mL/hr. Once again, the solution to be infused postoperatively will be prepared by pharmacy and blinded from the patient, nurse, and postoperative pain service providers.

Inclusion Criteria:

1. Male or Female
2. Aged 18 - 80 years
3. scheduled for primary elective cardiac surgery via median sternotomy
4. willingness to undergo psychosocial testing
5. willingness to participate in long-term follow up
6. willingness to be randomized to receive local anesthetic or saline infusion through PSPB catheters
7. access to an email and computer

Exclusion Criteria:

1. Allergy to opioids
2. allergy to bupivacaine
3. emergency surgery
4. unable to provide informed consent
5. weight less than 50kg