Analgesic Effectiveness of Transversus Thoracic Muscle Plane Block After Open-Heart Surgery

Severe postoperative pain is an ongoing challenge following cardiac surgery that has mainly been managed with opioids. To avoid opioid-related side effects, multimodal analgesic strategies are emerging, including transversus thoracic muscle plane (TTMP) block. In a report in the Journal of Pain Research, investigators led by Mohamed Ahmed Hamed, MD, examined the pain relieving efficacy of ultrasound-guided bilateral TTMP block after open-heart surgery and stated that it was a “promising and effective technique in reducing opioid consumption and controlling post-sternotomy pain after open-heart surgery via median sternotomy.”

The study recruited 70 patients who were scheduled for valve replacement or median sternotomy for adult congenital heart disease. Patients were randomized to either the block group, which had the ultrasound-guided TTMP block, or the control group, which had a sham block. The primary endpoint to assess analgesic efficacy was total fentanyl consumption in the first 24 hours. Secondary outcomes included pain score, time to first analgesic request, time to extubation, intensive care unit (ICU) stays, and hospital stay.

According to Dr. Hamed’s report, the total fentanyl consumption over the first 24 postoperative hours was significantly lower in the TTMP block group compared to the control group, with a mean difference of –158.286 (95% confidence interval [CI], –179.271 to –137.300; p ≤0.0001). Likewise, the at-rest pain scores during the postoperative period were 1.86 units lower in the block group (estimate, –1.80; 95% CI, –2.14 to –1.45; t = –10.323; p <0.0001), and pain scores with cough were 3.29 units lower (estimate, –3.29; 95% CI, –3.80 to –2.77; t = –12.703; p <0.0001). And, conversely, the time to the first analgesic request was “statistically significantly shorter in the non-block group (median, 3 hours) than the block group (median, 14 hours).”

The analgesic effectiveness of TTMP block after cardiac surgery was supported by the authors’ analysis. However, they included a recommendation for “further clinical trials over a large-scale population to ensure the clinical role of TTMP block as apart from the multimodal analgesic regimen,” as well as further studies “to evaluate the possibility and efficacy of catheter placement for multiple injections.”