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Complications of Intercostal Blocks and Ablations

Charles Amaral de Oliveira MD¹, Thais Khouri Vanetti MD1, and Karen Santos Braghiroli MD, FIPP²

¹ Centro de Controle da Dor, Campinas, SP, Brazil
²Maternity Hospital, SP, Brazil

Introduction

The intercostal nerves supply the major parts of the skin and musculature of the chest and abdominal wall. The block of these nerves was first described by Braun in 1907.

Anatomy

Bilaterally, we have 11 intercostal nerves and 1 subcostal nerve that correspond to the anterior branch of the 12th thoracic nerve (in general, we do not have the 13th rib). These nerves innervate the back, trunk, and upper abdomen, as well as the intercostal muscles [1, 2].

The intercostal nerves are located in the intercostal groove of each corresponding rib. They emerge bilaterally from T1 to T12 via the intervertebral foramina, and each nerve root divides into four branches: the gray and white rami communicantes, the posterior dorsal ramus and the ventral ramus (which gives rise to the intercostal nerve) [2].

The ventral ramus, composed of sensory and motor fibers, joins with its corresponding thoracic vein and artery to form the neurovascular bundle, with the vein located superiorly, the artery just below and the nerve more inferiorly [2]. This neurovascular bundle travels along the intercostal groove (in the lower part of each rib), three centimeters distant from where it exits the intervertebral foramen. It lies between the layers of the internal and innermost intercostal muscles [2, 3].

In the medial axillary region, the intercostal nerve gives off the lateral cutaneous branch, which divides into dorsal and ventral branches. The two are responsible for innervating the skin and subcutaneous tissue of the lateral torso and upper abdomen. The remaining intercostal nerve continues along the costal arch to terminate as the anterior branch in the sternal region and divides into lateral and medial branches that innervate the skin and subcutaneous tissue of the anterior torso and abdomen, including the sternal region and the rectus abdominis [2, 3].

The intercostal muscles and the parietal pleura are innervated by small branches of the intercostal nerves between T1 and T6 [2].

Indications

Rib fracture pain
Post-operative pain (after thoracotomy, sternotomy, and upper abdominal surgery)
Pain from costochondral joint dislocation
Herpetic or post-herpetic chest wall neuralgia
Chronic intercostal neuralgia; cancer pain involving the thoracic wall
Idiopathic intercostal neuralgia
Providing analgesia for thoracotomy and breast surgery [2, 3]
Sternum fracture
Chest-tube analgesia
Costochondritis
Blunt chest trauma analgesia [4]
Cancer or non-cancer pain in the chest wall [2]
To differentiate chest pain from visceral pain.