Postoperative analgesia after minimally invasive thoracoscopy: what should we do?

Many of the thoracic operations that previously required a thoracotomy incision can now be performed with several small incisions and video-assisted thoracic surgery (VATS). Although there have been reports of less pain and less impairment of pulmonary function with VATS compared with thoracotomy, 1 many VATS patients report significant acute and chronic postoperative pain. Treating thoracoscopic pain effectively and minimizing the later development of chronic pain requires familiarity with a wide spectrum of analgesic techniques. An important variable in the analgesic plan for VATS is the likelihood of converting to an open thoracotomy. Conversion may be due to technical difficulties, inadequate lung separation, or bleeding, and may be more likely when the surgeon has less experience with VATS. The likelihood of conversion to an open procedure must be assessed preoperatively. If a VATS procedure is converted to a thoracotomy and analgesia (such as an epidural) is not in place, the patient’s recovery may be impaired. If not wellcontrolled, postoperative thoracic pain can lead to splinting and may impair the patient’s ability to take deep breaths following thoracic surgery. It is difficult to state precisely the incidence of pain following thoracoscopy, as the extent and severity varies according to surgical technique, patient sensitivity, and anesthetic pain management. In a recent survey of Dutch thoracic surgery patients, 47% of the VATS patients reported chronic pain. 2 In an earlier study, the incidence of chronic pain was reported to be 36% in VATS patients undergoing wedge resection. 3 It might seem intuitive that performing the surgery by thoracoscopy, which utilizes small incisions, would lead to less postoperative pain. However, the introduction of trocars during thoracoscopy may injure intercostal nerves, and additional manipulation of these instruments during the surgery may traumatize these nerves further by compression against ribs. 4 If a lobectomy is being performed, an incision will need to be enlarged in order to extract the specimen, and a rib retractor may be required. Also, the duration of the surgery may be greater using VATS. Ipsilateral shoulder pain is a common complaint following VATS, and in one study, it was reported to be chronic in 10% of patients. 5