Randomised prospective study comparing the incidence of postoperative pain after phrenic nerve infiltration vs non-phrenic nerve infiltration on open thoracotomy - initial results

Abstract

Background. Thoracotomy is one of the most common surgical procedures performed worldwide for lung disease. Despite the advances in analgesia, patients still experience severe postoperative shoulder, central back and surgical incision site pain. The aim of this study was designed to assess whether the peri‐operative use of phrenic nerve infiltration (PNL) improve the postoperative pain and peak flow pressure during incentive spirometry. Methods. 46 patients undergoing single open lobectomy were randomly allocated into two groups (n=23 per group) to receive PNL or no PNL. The PNL group received 10mls of 0.25% Bupivacaine into the periphrenic fat pad. Preoperative assessments of spirometry reading and pain score were taken (rest and movement) using Likert scale pain scoring system. Postoperative assessments included peak flow and pain measurements at periodic intervals (1, 3, 6,12,24,48 and 72 hrs). Results. No demographic differences were observed between groups. An equivalent drop in spirometry readings from following surgery were observed in both groups (p=0.874). Greater shoulder pain was experienced in the no PNL group compared to PNL at 6 hours post‐surgery at rest (p=0.044) and with movement (p=0.005). Reduced back pain was reported in the PNL group up to 48 hours after surgery at rest (p=0.015) and with movement (p=0.014). Reduced pain at the incision site was also observed in the PNL group up to 48 hours at rest (p=0.040) and with movement (p=0.039). Conclusion. PNL is able to significantly reduce patient pain scores during the early post‐operative period, particularly during movement and around the incision site. The use of PNL may be of significant benefit to patients following surgery.