Table A1.
Ultrasound-guided regional nerve blocks in cardiac surgery—technical considerations.
| Block | Target Plane or Space | Target Nerve | Autonomic Blockade | Maximum Area of Sensory Loss | Surgical Approach—Best Fit | LA Volume for Single-Shot Block/Side # | Practice Patterns |
|---|---|---|---|---|---|---|---|
| PVB | TPVS | Dorsal and ventral rami of spinal nerve roots | Yes | Ipsilateral hemithorax | Sternotomy (BLB) | 20–25 mL if single-level (4th TP) or 4–5 mL with multilevel strategy | • Formal contraindication with anticoagulation |
| • Single-level equivalent to multilevel shots | |||||||
| ESP | ESM-to-TP | Dorsal and ventral rami of spinal nerve roots | Yes | Ipsilateral hemithorax | Sternotomy (BLB) | 20 mL at the 5th TP | • Bilevel-injection to improve LA spread |
| • Preemptive approach | |||||||
| PECS I | PMAJOR-to-PMINOR | Medial and lateral pectoral nerves | No | Narrow upper anterolateral chest wall | Minimally invasive thoracotomy (ULB) | 15 mL at the 3rd rib | • Inadequate for sternotomy |
| PECS II | PMAJOR-to-PMINOR (1) and SUPRA- or SUB-SAM (2) | PECS I, LTN and TDN | No | Wide upper anterolateral chest wall, including axilla | Minimally invasive thoracotomy (ULB) | 30 mL at the 3rd rib | • Inadequate for sternotomy |
| • Perform (1) after (2) with a single-pass approach | |||||||
| SAPB | SUPRA- or SUB-SAM | Lateral branches of ICN, including LTN and TDN with superficial SABP | No | Lateral chest wall | Minimally invasive thoracotomy (ULB) | 30–40 mL at the 4th -5th rib | • Inadequate for sternotomy |
| • Anterior spread with deep SAPB; posterior spread with superficial SAPB | |||||||
| PIFB | PMAJOR-to-EIM | Anterior branches of ICN | No | Parasternal | Sternotomy (BLB) | 20 mL at the 4th rib | • Combined |
| TTMPB | INNIM-to-TTM | Anterior branches of ICN | No | Parasternal | Sternotomy (BLB) | 20 mL at the 4th rib | • Combined |
#—Single-shot blocks refer to one time LA injection without catheter placement. Depending on block technique, either single-level or multilevel LA deposition may be performed. Commonly used LA drugs are ropivacaine and bupivacaine with concentrations ranging from 0.25% to 0.5%. Maximum recommended doses are 2 mg/kg for bupivacaine and 3 mg/kg for ropivacaine, respectively [87]. PVB, paravertebral block; ESPB, erector spinae plane block; PECS I and II, pectoralis nerve blocks I and II; SAPB, serratus anterior plane block; PIFB, pecto-intercostal fascial plane block; TTMB, thoracic transversus plane block; TPVS, thoracic paravertebral space; ESM, erector spinae muscle; TP, thoracic transversus process; PMAJOR, pectoralis major muscle; PMINOR, pectoralis minor muscle; SAM, serratus anterior muscle; EIM, external intercostal muscle; INNIM, innermost intercostal muscle; TTM, thoracic transversus muscle; LTN, long thoracic nerve; TDN, thoracodorsal nerve; ICN, intercostal nerve; ULB, unilateral block; BLB, bilateral block.