Continuous paravertebral block using a thoracoscopic catheter-insertion technique for postoperative pain after thoracotomy: a retrospective case-control study

BACKGROUND Thoracic epidural analgesia (EDA) is the gold standard for pain control after thoracotomy. However, because of its severe side effects, it is contraindicated in patients taking anticoagulant or antiplatelet drugs. In addition, some patients' anatomy can make epidural catheter insertion challenging. We therefore investigated the safety and efficacy of paravertebral block (PVB) using a thoracoscopic insertion technique, which avoids damage to the parietal pleura, for postoperative pain after thoracotomy. METHODS Patients who underwent thoracotomy with thoracic PVB in our hospital between March 2013 and March 2014 were examined retrospectively. Prior to creating the thoracotomy incision, a catheter for PVB was inserted percutaneously into the paravertebral space under thoracoscopic guidance. A matched-pair control group was selected at a 1:2 ratio from patients who underwent thoracotomy with thoracic EDA in our hospital from April 2011 to February 2013. Pain control and side effects were compared between groups and the results statistically analyzed. RESULTS Thoracic PVB was performed in 56 patients during this period, and 112 patients were selected as matched controls. Numeric Rating Scale scores on postoperative day 2 did not differ significantly between the PVB group (3.25 ± 1.80) and the EDA group (3.56 ± 2.05) (p = 0.334). In terms of side effects, urinary retention occurred less frequently in thoracic PVB patients (p = 0.03). CONCLUSION Under the conditions of the present study, continuous thoracic PVB was at least as effective as epidural analgesia for postoperative pain control after thoracotomy with lung resection.