Fig. 2
From: Fascial plane blocks for cardiothoracic surgery: a narrative review
A Superficial parasternal block. At level of second and fourth intercostal spaces, the local anesthetic is injected between the pectoralis major muscle and the external intercostal muscles. PMM, pectoralis major muscle; EIM, external intercostal muscle; N, needle; LA, local anesthetic. B Superficial parasternal block–modified approach. The injection on the dome of the rib allows a more homogeneous and longitudinal diffusion of local anesthetic, obtaining a better dermatomal coverage. PMM, pectoralis major muscle; IIM, internal intercostal muscle; EIM, external intercostal muscle; N, needle; LA, local anesthetic