The Relationship Between NLR and PONV and ESPB

The patient assumes a prone position, and the appropriate lumbar vertebral level is identified using ultrasound, based on the preoperative markings of the surgical incision site. After disinfection, the ultrasound probe is placed in the parasagittal direction, 3 centimeters lateral to the midline, to identify the corresponding lumbar transverse process and the overlying erector spinae and latissimus dorsi muscles. Using an in-plane technique, the needle is advanced, and when the needle tip contacts the bony transverse process and there is no blood or gas upon aspiration, 2-3 mL of isotonic saline solution is injected to confirm the correct needle position. Local anesthetic is then injected between the erector spinae muscle and the transverse process. The spread of the local anesthetic in the deep fascial plane within the erector spinae muscle can be visualized using ultrasound.

The patient is placed in a prone position, and the appropriate lumbar vertebral level is determined using ultrasound based on the preoperative markings of the surgical incision site. After disinfection, the ultrasound probe is positioned in the parasagittal direction, 3 centimeters lateral to the midline, to identify the corresponding lumbar transverse process, erector spinae, and latissimus dorsi muscles above it. Using an in-plane technique, the needle is advanced, and when the needle tip contacts the bony transverse process, and there is no blood or gas upon aspiration, 2-3 milliliters of isotonic saline solution are injected to confirm the correct needle position. Subsequently, 20 milliliters of 0.9% physiological saline is injected between the erector spinae muscle and the transverse process. The diffusion of the physiological saline in the deep fascial plane within the erector spinae muscle can be visualized using ultrasound.