Interpleural or Intrapleural Block

Intrapleural or interpleural blocks consist of injecting a local anesthetic within the pleural cavity without creating a pneumothorax. This technique elicited some enthusiasm 10 years ago but has not found an established place in pediatric anesthesia. Biliary duct surgery and parietal pain due to thoracotomy are the most commonly accepted indications, but the quality of analgesia varies, and systemic absorption is high, exposing the patient to systemic toxicity.^{[283] [284]} The technique is usually performed with a 22- or 20-gauge Tuohy needle connected to an LOR syringe, as is used for identifying the epidural space. With the patient in the semiprone or ventral position, usually after completion of surgery, the eighth intercostal space is identified. The needle is connected to the syringe filled with 1 to 3 mL of gas (preferably medical carbon dioxide) or fluid (preferably local anesthetic), and it is introduced perpendicular to the skin in the midaxillary line (but any other point is suitable) immediately below the eighth rib and with the bevel turned cephalad. A first LOR is felt as the intercostal membrane is pierced, and a second one occurs when the parietal pleura is traversed with a characteristic click. The local anesthetic is injected while avoiding air penetration when disconnecting the syringe, and a catheter is introduced in the interpleural space. A bolus dose (0.6 to 0.8 mg/kg) of 0.25% or 0.2% ropivacaine is injected, followed by a continuous infusion of 0.6 to 0.8 mg/kg/hour. The quality of analgesia produced by this block is inferior to that of epidural anesthesia and intercostal nerve blockade.^[285]