Fig. 10
From: Fascial plane blocks for cardiothoracic surgery: a narrative review
A ESPB: the needle is advanced with an in-plane approach in caudo-cranial direction to reach the interfascial plane between the transverse process and the erector spinae muscle. B Ultrasound visualization of the ESPB catheter between the ESM and the transverse process. ESM, erector spinae muscle; LA, local anesthetic; N, needle; T4, transverse process