Ultrasound-Guided Transverse Thoracic Muscle Plane Injection vs. Topical Spraying of Papaverine for LIMA Harvesting: A Pilot Study

Although the effect of topical papaverine on the left internal mammary artery (LIMA) flow is a well-known method, papaverine hydro dissection is applied to the transverse thoracic muscle plane is unknown. This study aims to investigate the effect of ultrasound-guided transverse thoracic muscle plane papaverine injection on LIMA flow. METHODS: ASA II-III, 40 patients who underwent coronary artery bypass grafting surgery, were randomly divided into two groups. Group topical papaverine (Group TP, n=20) and Group ultrasound-guided papaverine (Group USP, n=20). In Group TP, 10 mg papaverine in 10 mL saline was administered topically after LIMA harvesting. In Group USP, ultrasound-guided transverse thoracic muscle plane papaverine injection with the same solution preoperatively. Trans-time flow measurements (TTFM), LIMA harvesting time, and surgeon satisfaction were recorded. RESULTS: There was no difference in LIMA free flows before anastomosis between Group USP and Group TP (111.35±69.76 vs. 92.15±46.76, respectively, p=0.185). There was no significant difference between the groups in TTFM values evaluated after anastomosis (p> 0.05). LIMA harvesting time was statistically shorter in Group USP than Group TP (13.90±3.01 vs. 16.65±4.50 respectively, p=0.049). Surgeon LIMA harvest satisfaction was statistically significantly higher in group USP (p=0.029). DISCUSSION AND CONCLUSION: We think that papaverine injection via ultrasound-guided transverse thoracic muscle plane may be an alternative method to topical application to prevent LIMA spasm.