BACKGROUND: Mid-axillary transversus abdominis plane block (TAP-B) and subcostal TAP-B have become well-known blocks to provide considerable analgesia for abdominal surgery. However, proper approach and adequate volume of injectate have not still been clarified. In this study, a combination of mid-axillary TAP-B and subcostal TAP-B was performed in cadavers to establish the spread of injectate and segmental nerve involvement. METHODS: Ultrasound-guided dye injections (10 ml each) into the TAP were performed with mid-axillary and subcostal approaches. Injections were performed for hemiabdominal walls of 4 Thiel's embalmed human cadavers. Dye spread and nerve involvement were evaluated by dissection 10 min after the injections. RESULTS: All 7 hemiabdominal walls were successfully injected and dissected after 1 pilot study. Thoracic nerves (T7-12) and the first lumbar nerve (L1) were found. Segmental nerves T7 (14%), T8-11 (100%), T12 (71%), and L1 (43%)were involved. CONCLUSIONS: This study demonstrated that the combination of ultrasound-guided mid-axillary TAP-B and subcostal TAP-B involve T8-L1 nerves. This technique can be used not only in lower abdominal surgery but also in upper abdominal surgery.
BACKGROUND: Mid-axillary transversus abdominis plane block (TAP-B) and subcostal TAP-B have become well-known blocks to provide considerable analgesia for abdominal surgery. However, proper approach and adequate volume of injectate have not still been clarified. In this study, a combination of mid-axillary TAP-B and subcostal TAP-B was performed in cadavers to establish the spread of injectate and segmental nerve involvement. METHODS: Ultrasound-guided dye injections (10 ml each) into the TAP were performed with mid-axillary and subcostal approaches. Injections were performed for hemiabdominal walls of 4 Thiel's embalmed human cadavers. Dye spread and nerve involvement were evaluated by dissection 10 min after the injections. RESULTS: All 7 hemiabdominal walls were successfully injected and dissected after 1 pilot study. Thoracic nerves (T7-12) and the first lumbar nerve (L1) were found. Segmental nerves T7 (14%), T8-11 (100%), T12 (71%), and L1 (43%)were involved. CONCLUSIONS: This study demonstrated that the combination of ultrasound-guided mid-axillary TAP-B and subcostal TAP-B involve T8-L1 nerves. This technique can be used not only in lower abdominal surgery but also in upper abdominal surgery.