Continuous Interpleural Block

Patient Position:
Lateral decubitus with the arm dangling anteriorly and cephalad so as
to rotate the scapula forward and expose the posterolateral chest wall.

Indications:
Postoperative analgesia following mastectomy, nephrectomy, and
cholecystectomy. Analgesia for rib fractures, pancreatitis, neuralgia,
and invasive tumor of the chest wall, flank, and retroperitoneum.

Needle Size and Catheter: 18-gauge epidural needle and 20- or 21-gauge catheter.

Volume and Infusion Rate: Initial bolus of 20 to 30 mL 1% lidocaine followed by continuous infusion of 6 to 8 mL/hour 1% lidocaine.

Anatomic Landmarks: The seventh or eighth intercostal space, the scapula, and the posterior axillary line (Fig. 30-1A).

Approach and Technique:
The site of needle insertion is at the seventh or eighth intercostal
space at the level of the tip of the scapula and the cephalad border of
the rib in a vertical direction perpendicular to the chest wall. Once
inserted to a depth of 1 cm into the intercostal muscles, a syringe
(with its plunger removed) is attached to the needle. The open syringe
barrel is filled with saline. The needle is then slowly advanced while
observing for both a “clicking” sensation and a downward movement (the
“falling column”) of the saline as it is drawn into the chest by the
negative pleural pressure. The syringe is removed (Fig. 30-1B)
and the epidural catheter threaded 6 to 10 cm into the interpleural
space. The Tuohy needle is removed, and the catheter is secured with 12
mm × 100 mm Steri-Strip (3M, St. Paul, MN) and covered with a
transparent dressing (Fig. 30-1C).