Analgesic Efficacy of Intravenous Acetaminophen After Video-assisted Thoracic Surgery

We will study the efficacy of FDA approved intravenous (IV) acetaminophen ("Ofirmev", © 2011 Cadence Pharmaceuticals, Inc.) in reducing opioid consumption after minimally invasive thoracic surgery in a double blind randomized trial. This drug has been shown in Europe to reduce the need for patient controlled analgesia and the total dose of opioids, which have serious side effects in thoracic surgery patients. We will compare the use of IV patient-controlled morphine (PCA) in two groups of subjects in treating postoperative pain. One group of subjects will receive IV acetaminophen every six hours beginning within 30 minutes before surgical end time and continuing for 24 hours plus IV morphine PCA, and the other group will receive IV placebo every six hours plus IV morphine PCA, a standard treatment for postoperative pain. We will determine if IV acetaminophen reduces post-operative morphine requirements (primary end point). We will also assess subject pain scores and post-operative complications associated with pain management as secondary end points. Our hypothesis is that the study arm receiving intravenous acetaminophen will have lower total morphine consumptions compared to the placebo group.

Inclusion criteria

• Any elective VATS patients with low probability of conversion to thoracotomy as determined by surgery.
• Ages 18-99
• American Society of Anesthesiologists Physical Status I-III, hemodynamically stable
• Male or female

Exclusion criteria

• Age less than 18.
• Patient refusal
• High probability of conversion to thoracotomy as determined by surgeon
• Conversion of procedure to thoracotomy (subjects will be withdrawn if VATS procedure is converted to thoracotomy, as thoracotomy is more invasive and will likely require additional analgesia such as neuraxial and regional anesthesia).
• Scheduled procedure of VATS Pleurodesis/decortication
• History of Interstitial Lung Disease
• Emergency case
• Known allergy/adverse reaction to acetaminophen, morphine, or fentanyl
• History of drug or alcohol abuse
• Patients on preoperative analgesic therapy within one week of surgery
• Contraindication to self administered morphine (unable to understand PCA)
• Need for postoperative mechanical ventilation
• Necessary major deviation for intraoperative study protocol as per the discretion of the intraoperative attending anesthesiologist
• History of congestive heart failure, renal failure, liver failure
• Pregnant or breastfeeding women
• Weight less than 51 kg