Postoperative analgesia in thoracic surgery: A comparison between continuous paravertebral nerve block and continuous incisional infusion with OnQ pain relief system

Abstract

Objectives: Thoracotomy is one of the most painful surgical stimuli and inadequate management of postthoracotomy pain is often associated with pulmonary and cardiac complications. The aim of this prospective, randomized, double-blinded study was to compare continuous paravertebral block versus continuous incisional infusion with OnQ Pain Relief System. Methods: Forty eight patients, undergoing thoracotomy for elective lobectomy, were randomized to receive a continuous paravertebral infusion of bupivacaine 0.25% through an elastomeric pump which delivers 0.1 mL/Kg/h (group A) or a continuous incisional infusion of bupivacaine 0.25% at an infusion rate of 4 mL/h with OnQ Pain Relief System (group B). Both infusions were started before wound closure, and continued for 48 postoperative hours. General anaesthesia was standardized. In the recovery room, patients were provided with intravenous morphine patient-controlled analgesia (PCA). Visual analogue scale at rest (VASr) and when coughing (VASi), rescue patientcontrolled analgesia morphine consumption, hemodynamic, time to ambulation and side-effects were evaluated within 48 h. Results: The two groups were comparable regarding to patients' number and characteristics, type of surgery, time to ambulation and side-effects; postoperative hemodynamic profile was stable in all the patients. Absolute pain scores were low in both groups; patients in group A reported significant lower VASr and VASi values during the postoperative 48 hours compared with group B (p<0.001). Total morphine consumption and PCA requests number were significantly lower in group A than in group B (p= 0.05 and p< 0.01). Conclusions: Continuous incisional infusion of local anesthetic is not as effective as paravertebral analgesia after thoracotomy. © 2012 De Cosmo G, et al.