Oxycodone/Naloxone in the Management of Pain After Thoracic Surgery. A Pilot Study

Introduction: Thoracic surgery can produce severe postoperative pain that can impair patient's outcome and quality of life during several weeks after surgical procedure. An immediate postoperative adequate pain relief is important to improve patient's performance. Many approaches are available for pain management sometime in order to improve patient's comfort avoiding respiratory insufficiency due to hypoventilation for pain. We explore an analgesic strategy by oral route of Oxycodone-Naloxone prolonged release tablets after thoracotomy. Methods: 16 consecutive patients undergoing thoracotomy were enrolled in this study conducted at Agostino Gemelli Hospital in Rome. All patients received general anesthesia and same intraoperative pain management: intercostal block performed by surgeon under direct vision before chest closure, elastomeric pump with 15 mg morphine 2 ml/h for 24 hours, ketoprofen 100 mg at the end of operation. The morning after surgery, all patients started oral Oxycodone-Naloxone 5/2,5 mg every 12 hours and was discontinued intravenous (IV) opioid infusion. If pain exceeded a Numerical Rating Scale (NRS) Score of 3, postoperative rescue analgesia included 1 g paracetamol IV (up to three times a day). Postoperative clinical assessments started in the evening after surgery and then daily. Pain intensity was evaluated at rest and after movement according to NRS score. Patients continued this analgesic regimen after discharge for three weeks in order to complete respiratory rehabilitation program and then were controlled at ambulatory of pain therapy for suspension of therapy. Results: 8 males and 8 females, ASA II/III=10/6, mean age 63,1±8, undergoing thoracotomy enrolled in this study, After surgery, pain intensity remained well controlled, both at rest (mean NRS: 2,56, 1.31, 0,43 respectively during 24, 48, 72 hours) and upon movement (mean NRS:4,62, 3,37, 2,5). Rescue paracetamol was require almost exclusively in the first postoperative day. No adverse effects were registered. No neuropatic thoracic pain has been reported in follow up. Discussion: Postoperative pain after thoracic surgery is usually severe and it could continue for several weeks, promoting the development of chronic pain difficult to treatment. We studied the usefulness of Oxycodone/Naloxone tablets, usually used in the treatment of chronic pain, that resulted effective and well tolerated without adverse effects, also at low dosage, in the immediate postoperative phase. We believe that oral route administration of opioids is an interesting strategy reducing severity of acute pain.