Ultrasound-guided Pectoral-intercostal Fascial Plane Block for Patients With Severe Pain After Coronary Artery Bypass Graft Surgery: A Feasibility Study

Post-sternotomy pain (PSP) is a common complication after cardiac surgery, occurring up to 49% of patients at rest according to one prospective study. In addition to decreased patient satisfaction, PSP has been associated with adverse post-operative events including delirium, hypertension, tachycardia, arrhythmias, respiratory complications and persistent post-surgical pain.

While most PSP can be effectively managed with opioids, non-steroidal anti-inflammatory drugs (NSAIDs) or central neuraxial blockades, these analgesia techniques also carry a high incidence of adverse effects. The use of opioid analgesics, for example, can contribute to respiratory depression, nausea, and delirium. While NSAIDs can be effective analgesics, they are also associated with postoperative kidney injury after cardiac surgery, a significant risk factor for mortality. Further, intrathecal or epidural techniques have a significant failure rate, and may be associated with severe hypotension, and devastating consequences such as neuraxial hematoma or infection. As such, alternative methods that are effective and safe for treating severe PSP remain elusive.

Peripheral regional anesthetic techniques have been demonstrated to reduce opioid consumption and may also provide improved respiratory mechanics. The pecto-intercostal fascial block (PIFB) was recently described in a descriptive letter by de la Torre and colleagues for anesthesia during breast surgery. In this technique, local anesthetic is infiltrated into the fascial plane between pectoralis major and the intercostal muscles lateral to the sternum to anesthetize the anterior cutaneous branches of the intercostal nerves. While the authors do state improved analgesia for breast surgery in their experience with use of this block, specific outcomes such as pain scores or opioid consumption are not reported.

The anterior cutaneous branches of the T2 to T6 intercostal nerves are thought to be the major sensory innervators of the sternum.

Using the same PIFB described above, the investigators have recently treated a patient successfully with severe PSP after CABG. To our knowledge, there is limited literature describing the use of this block for treatment of PSP. The investigators plan to conduct a prospective feasibility study to 1) assess the feasibility of using PIFB to reduce PSP in post-coronary bypass and/or valvular surgery patients and 2) obtain subjective data with regard to patient satisfaction and reduction in opioid consumption use that may help guide future, well-powered, randomized studies. 3) Describe any adverse outcomes following PIFB.