Efficacy of 0.2% ropivacaine on post thoracotomy ipsilateral shoulder pain either via intrapleural instillation or phrenic nerve infiltration

Background: Post thoracotomy ipsilateral shoulder pain (PTISP) is the most common complication following thoracotomy and unfortunately PTISP has not given much attention. There are many hypothesis for it's etiology
Objectives: To study the effect of Ropivacaine on PTISP given via either Phrenic nerve infiltration or via Intrapleural Instillation with epidural analgesia as the standard mode of analgesia in both the groups.
Study Design: Prospective observational study.
Methods: 80 patients were divided into 2 groups, “Group A (Intrapleural instillation) received 40ml of 0.2% Ropivacaine with 1:100000 epinephrine into basal chest drain at the end of the surgery” and “Group B (Phrenic nerve infiltration) received 10ml of 0.2% Ropivacaine into phrenic nerve infiltration prior to chest closure”. Postoperatively patients were assessed for PTISP using VAS score at 0, 1,3 , 6, 12, 24,36 and 48 hours(h). The number of rescue analgesia required were recorded.
Results: PTISP was relieved significantly in Group B as compared to Group A. The number of rescue analgesic required was less in Group B than in Group A (P value<0.05). Postoperative hemodynamics were stable in Group B than in Group A.
Conclusion: Ropivacaine is effective in relieving PTISP via Phrenic Nerve Infiltration, it has significantly reduced the incidence and delayed the onset of PTISP as compared to Intrapleural Instillation and was not associated with any adverse effects.