Hemodynamic changes after intercostal nerve block with bupivacaine-epinephrine solution

Postthoracotomy pain management

The following techniques appear efficacious in controlling postthoracotomy pain and reducing the amount of systemic opioids consumed: continuous intercostal blockade, paravertebral blockade, and epidural opioids and/or anesthetics. The combination of thoracic epidural opioid and local anesthetic is very effective at relieving postthoracotomy pain, however, considerable experience is required for insertion of the thoracic epidural catheter and postoperative respiratory monitoring. Intercostal and paravertebral catheters can be inserted intraoperatively under direct visualization, to reduce complications of insertion. One-time intraoperative intercostal blockade may effectively reduce postoperative pain in the first day, but is not a practical long-term method for postthoracotomy pain. The effectiveness of interpleural analgesia, even with proper technique, appears inferior to epidural and other regional techniques. We have incorporated the principles outlined in this review into our general thoracic surgery protocol, as detailed in Fig. 1. Every patient is assessed preoperatively for epidural catheter placement. Contraindications include low platelet count (< 100,000), abnormal coagulation profile, medicinal anticoagulation (aspirin and nonsteroidal anti-inflammatories are not contraindications), bony spinal abnormalities, or neurological disorders. The T5/6 interspace is our preferred level, but T10 can work well with an increased dose of bupivacaine. Upon completion of the muscle sparing, minimal-access thoracotomy, we close the wound and perform a percutaneous intercostal nerve block (two ribs above and three below the incision). We then use patient-controlled epidural analgesia, with a basal infusion of bupivacaine and hydromorphone. To supplement inadequate or nonfunctioning epidurals, intravenous patient-controlled opioids are added. When choosing an approach to postthoracotomy pain management, the thoracic surgeon and anesthesiologist must consider the following: (1) the physician's experience, familiarity and personal complication rate with specific techniques; (2) the desired extent of local and systemic pain control; (3) the presence of contraindications to specific analgesic techniques and medications; and (4) availability of appropriate facilities for patient assessment and monitoring postthoracotomy. Refinements in surgical technique including limited or muscle-sparing thoracotomy, video-assisted thoracoscopic surgery (VATS) and robotic surgery may lessen the magnitude of postthoracotomy pain. We encourage all thoracic surgeons to be knowledgeable of available techniques and maintain a protocol to generate a database for periodic assessment of safety and efficacy.

Multiple intercostal blocks by a single injection? A clinical and radiological investigation

Three different techniques for producing multiple intercostal nerve blocks using bupivacaine were compared in volunteers. The techniques used were multiple injections at intercostal nerves 7-11, or a single injection employing a needle or a catheter inserted in the 9th intercostal space. The injections were made at the costal angle. The anatomical spread of a mixture of a local anaesthetic and a radio-opaque fluid following the single injection technique at the ninth intercostal space or at the subcostal space was evaluated by computerized x-ray tomography (CT). The distribution of cutaneous analgesia/hypalgesia following all techniques was evaluated by pin prick. No spread of the local anaesthetic to adjacent intercostal spaces or to the paravertebral space could be shown by CT. The distribution of cutaneous analgesia was limited to three segments or less following a single injection. No difference in blood levels of bupivacaine could be found. It is concluded that the single injection technique of producing multiple intercostal nerve blocks is inferior to the multiple injection technique.

Anatomy of the intercostal nerve: its importance during thoracic surgery

Complications from attempts to block the intercostal nerves intraneurally before closure of a thoracotomy have resulted in hypotension with or without spinal block. Placement of a chest tube has resulted in transection of the intercostal nerve. The first of these complications can be avoided by not attempting intraneural block of the nerves intrathoracically. Avoidance of the latter requires careful dissection of the intercostal spaces and identification of the intercostal nerve, as opposed to stab insertion of a chest tube.

Subtotal spinal anaesthesia as a complication of intrathoracic intercostal nerve blocks

A patient developed subtotal spinal anaesthesia following intercostal nerve block performed by the surgeon during thoracotomy. Direct intraneural injection of bupivacaine appeared to be the most likely mechanism for this complication.