Efficacy of Ultrasound-Guided Pectointercostal Fascial Block Versus Control and Alternative Regional Techniques in Cardiac Surgery: A Systematic Review and Meta-Analysis with Dose–Response Analysis

Background and Objectives: Ultrasound-guided pectointercostal fascial block (USG-PIFB) is increasingly used for post-sternotomy analgesia, but its efficacy remains uncertain. Prior meta-analyses pooled ultrasound-guided blocks with surgeon-performed infiltration, introducing heterogeneity. We aimed to determine the analgesic efficacy of USG-PIFB in adult cardiac surgery by restricting inclusion to ultrasound-guided techniques. Materials and Methods: Six databases were searched through December 2025, with an update search of open sources and trial registries in September 2026, for randomized controlled trials comparing USG-PIFB with control (Comparison 1) or with an alternative regional technique (Comparison 2) in adults undergoing sternotomy. The primary outcome was 24-h opioid consumption in intravenous morphine milligram equivalents. Random-effects meta-analysis (REML, Knapp–Hartung), subgroup, sensitivity and meta-regression analyses, an exploratory trial sequential analysis and GRADE assessment were performed.