The external oblique intercostal block: Anatomic Evaluation and Case Series

TY - JOUR

T1 - The external oblique intercostal block

T2 - Anatomic Evaluation and Case Series

AU - Elsharkawy, Hesham

AU - Kolli, Sree

AU - Soliman, Loran Mounir

AU - Seif, John

AU - Drake, Richard L

AU - Mariano, Edward R

AU - El-Boghdadly, Kariem

N1 - Publisher Copyright: © The Author(s) 2021. Published by Oxford University Press on behalf of the American Academy of Pain Medicine. All rights reserved. For permissions, please e-mail: [email protected].

PY - 2021/11/26

Y1 - 2021/11/26

N2 - STUDY OBJECTIVE: We report a modified block technique aimed at obtaining upper midline and lateral abdominal wall analgesia: the external oblique intercostal (EOI) block. DESIGN: A cadaveric study and retrospective cohort study assessing the potential analgesic effect of the EOI block. SETTING: Cadaver lab and operating room. PATIENTS: Two unembalmed cadavers and 22 patients. INTERVENTIONS: Bilateral ultrasound-guided EOI blocks on cadavers with 29 mL of bupivacaine 0.25% with 1 mL of India ink; single-injection or continuous EOI blocks in patients. MEASUREMENTS: Dye spread in cadavers and loss of cutaneous sensation in patients. MAIN RESULTS: In the cadaveric specimens, we identified consistent staining of both lateral and anterior branches of intercostal nerves from T7 to T10. We also found consistent dermatomal sensory blockade of T6-T10 at the anterior axillary line and T6-T9 at the midline in patients receiving the EOI block. CONCLUSIONS: We demonstrate the potential mechanism of this technique with a cadaveric study that shows consistent staining of both lateral and anterior branches of intercostal nerves T7-T10. Patients who received this block exhibited consistent dermatomal sensory blockade of T6-T10 at the anterior axillary line and T6-T9 at the midline. This block can be used in multiple clinical settings for upper abdominal wall analgesia.

AB - STUDY OBJECTIVE: We report a modified block technique aimed at obtaining upper midline and lateral abdominal wall analgesia: the external oblique intercostal (EOI) block. DESIGN: A cadaveric study and retrospective cohort study assessing the potential analgesic effect of the EOI block. SETTING: Cadaver lab and operating room. PATIENTS: Two unembalmed cadavers and 22 patients. INTERVENTIONS: Bilateral ultrasound-guided EOI blocks on cadavers with 29 mL of bupivacaine 0.25% with 1 mL of India ink; single-injection or continuous EOI blocks in patients. MEASUREMENTS: Dye spread in cadavers and loss of cutaneous sensation in patients. MAIN RESULTS: In the cadaveric specimens, we identified consistent staining of both lateral and anterior branches of intercostal nerves from T7 to T10. We also found consistent dermatomal sensory blockade of T6-T10 at the anterior axillary line and T6-T9 at the midline in patients receiving the EOI block. CONCLUSIONS: We demonstrate the potential mechanism of this technique with a cadaveric study that shows consistent staining of both lateral and anterior branches of intercostal nerves T7-T10. Patients who received this block exhibited consistent dermatomal sensory blockade of T6-T10 at the anterior axillary line and T6-T9 at the midline. This block can be used in multiple clinical settings for upper abdominal wall analgesia.

UR - http://www.scopus.com/inward/record.url?scp=85122489387&partnerID=8YFLogxK

U2 - 10.1093/pm/pnab296

DO - 10.1093/pm/pnab296

M3 - Article

C2 - 34626112

SN - 1526-2375

VL - 22

SP - 2436

EP - 2442

JO - Pain Medicine

JF - Pain Medicine

IS - 11

ER -