Ipsilateral shoulder pain after thoracic surgery procedures under general and regional anesthesia – a retrospective observational study

BACKGROUND Ipsilateral shoulder pain (ISP) is a common complication of mixed etiology after thoracic surgery (its prevalence is estimated in the literature at between 42% and 97%). It is severe and resistant to treatment (patients complain of pain despite effective epidural analgesia at the surgical site). AIM OF THE STUDY The aim of this retrospective, observational study was to evaluate the prevalence of ISP in patients operated on in our facility and to determine the risk factors for ISP development. MATERIAL AND METHODS 68 patients after thoracotomy or videothoracoscopy (video-assisted thoracic surgery - VATS) conducted under general and regional anesthesia were enrolled in the study and divided into two groups: group I without ISP and group II with postoperative ISP. We recorded age, sex, BMI, duration of surgery, type of surgery, type of regional anesthesia, and, in patients with epidural anesthesia, level of catheter placement. RESULTS Statistically significant differences between the groups were obtained for BMI (24.67 and 27.68, respectively; p = 0.049), type of surgery (24% for thoracotomy and 0% for VATS, p = 0.026), and level of epidural catheter placement (4.35% for catheters placed at the level of Th5 or higher and 40.47% for catheters placed below Th5; p = 0.003). CONCLUSIONS The prevalence of ISP in our medical center amounts to 24% of thoracotomy patients. The fact that the difference in ISP prevalence was significantly related to the level of epidural catheter placement is consistent with the theory that ISP is related to phrenic nerve innervation. Moreover, epidural catheter placement is a modifiable factor, which can be used to reduce the prevalence of post-thoracotomy ISP.