Pectointercostal Fascial Plane Block (PIFB) Alone Versus PIFB With Rectus Sheath Block (RSB) in Cardiac Surgery

This is a single center, prospective, randomized, controlled, double-blinded study. We anticipate recruitment of 62 subjects, with 25-30 in each group.

Primary Outcomes:

Pain scores on a 0-10 visual analog scale (VAS) at rest and with deep breathing at 1, 3, 6, 12, 18, and 24 hours post-extubation between subjects receiving PIFB + RSB versus subjects receiving only PIFB.

Total cumulative opioid consumption at 24 and 48 hours post-operatively.

Secondary Outcomes:

• Intraoperative total opioid consumption
• Change from baseline on incentive spirometry at 1, 3, 12, and 24 hours post-extubation
• Time from ICU arrival to liberation from mechanical ventilation
• QoR-15 (Quality of Recovery) score23 24 hours after extubation
• Hospital and ICU length of stay

Preoperative Management :

Subjects will be randomized on the morning of surgery to receive bilateral PIFB and bilateral RSB with local anesthetic versus bilateral PIFB with local anesthetic and bilateral RSB with saline (placebo).

Intraoperative Management All subjects will receive the standard of care anesthetic regimen for their cardiac surgery.

Postoperative Management Each PIFB will be performed with 15 mL of 0.25% bupivacaine with 5 mcg/ml of epinephrine, and bilateral RSB will be performed with an additional 20 mL of 0.25% bupivacaine with 5 mcg/ml of epinephrine (10mL on each side).

Postoperative Evaluation:

Evaluation of acute postoperative pain intensity using a 0-10 visual analog scale (VAS) will be undertaken at the following time points, both at rest and with deep breathing:

• 1, 3, 6, 12, 18, and 24 hours post-extubation Incentive spirometry will be assessed at 1, 3, 12, and 24 hours post-extubation, with three measures taken at each time point in order to compare postoperative performance with baseline spirometry.

Review of the medical chart will be made post-operatively to gather other data, including total intraoperative oral morphine equivalent consumption, cumulative opioid consumption at 24 and 48 hours, time from ICU arrival to tracheal extubation, hospital and ICU length of stay, and QoR-15 (Quality of Recovery) score administered 24 hours after extubation (with margin of error of 18-30 hours to avoid waking patients in the middle of the night) . Occurrences of any adverse events reported by the subject or medical team will also be collected.

Inclusion criteria

• Subjects scheduled for cardiac surgery involving primary median sternotomy and mediastinal chest tubes.
• Age 18-85 years of age
• BMI 18-50 kg/m2
• Weight > 60 kg

Exclusion criteria

• Left ventricular ejection fraction (LVEF) < 30%
• Preoperative, intraoperative, or immediate post-operative placement of intra-aortic balloon pump or deployment of extra-corporeal membrane oxygenation (ECMO)
• Inability to understand or speak English
• Allergy to bupivacaine or other amide local anesthetic
• Contraindication to peripheral nerve block (e.g. local infection, previous trauma to the block site)
• Chronic opioid consumption (daily oral morphine equivalent of >20 mg) in the past three months
• Severe pulmonary or hepatic disease
• Neurological deficit or disorder
• Suspected or known addiction to or abuse of illicit drug(s), prescription medicine(s), or alcohol within the past two years
• Uncontrolled anxiety, schizophrenia, or other severe psychiatric disorder