To Study the Efficacy of Ultrasound Guided Pecto-Intercostal Fascial Plane Block in Patients Undergoing Midline Sternotomy in Open Cardiac Surgery: A Randomized Prospective Comparative Study.

Abstract

Background: The incidence of acute poststernotomy pain after cardiac surgery is 80%1. Pecto-intercostal fascial plane block (PIFB) adjacent to the sternum anesthetizes the anterior cutaneous branches of the intercostal nerves and may provide effective analgesia after sternotomy.

Methodology: A randomized controlled, double-blinded, prospective comparative trial was conducted at a tertiary care center on patients of midline sternotomy between 18 and 65 years and NYHA Class 2 and 3 for open cardiac surgery with the primary aim to evaluate analgesia on deep breathing after 3 hours of PIFB block bilaterally. A total of 60 patients were enrolled and randomly divided into three groups. PIFB was administered bilaterally before extubation, with 15 ml 0.125% bupivacaine plain (Group B), and bupivacaine+ clonidine 0.25 mcg/kg (Group B+C). Group C did not receive any intervention. All patients received acetaminophen 1 gram three times a day and injectable tramadol 1 mg/kg as a rescue analgesic.

Results: Baseline characteristics were similar among all the groups. The Numeric Rating Scale (NRS) for pain was statistically lower (P < 0.05) in Groups B and B+C compared to Group C at rest, deep breathing, and coughing at 3, 6, and 12 hours after extubation. NRS on deep breathing in Groups B, B+C, and C was {(2.3, 1.5, 4.4) at 3 hours, (2.3, 1.6, 4.3) at 6 hours, (2.8, 2.1, 3.9) at 12 hrs, and {(4.3, 3.5, 3.6)} at 24 hours after extubation. The peak expiratory flow rate was the highest in Group B. Rescue analgesia was not required in Group B.

Conclusion: PIFB reduces sternotomy pain compared to the control group on deep breathing at 3 hours after block, with delayed requirement of rescue analgesia and improved respiratory mechanics in terms of peak expiratory flow rate at all time points. There is no benefit from adding clonidine.