Intermittent peri-tubal instillation of dexamethasone and ropivacaine on postoperative analgesia after percutaneous nephrolithotomy: A prospective randomized controlled trial.

ABSTRACT

OBJECTIVES: Percutaneous nephrolithotomy and placement of nephrostomy tube are performed for renal stones >2 cm in diameter. Attempts have been made to infiltrate local anesthetics with or without adjuvants into the surgical site to reduce pain. We hypothesized that there would be a significant prolongation of the analgesic effect of local anesthetic instillation along the nephrostomy tube due to the adjuvant dexamethasone. METHODS: After ethical approval and Clinical Trials Registry - India registration (CTRI/2020/03/024332), 64 American Society of Anesthesiologists classification 1 and 2 adult patients were enrolled in this randomized double-blinded prospective study divided into Group R-received 20 mL 0.2% Ropivacaine and Group R + D-received 20 mL 0.2% Ropivacaine with dexamethasone 8 mg, injected through a multi-lumen wound infiltration catheter. RESULTS: The demographic profile of patients was similar in both groups. The mean duration of analgesia was longer in Group R + D (21.3 ± 2.1 hrs) versus Group R (10 ± 1.9 hrs, P = 0.001). The mean numeric rating scale scores of Group R + D were significantly lower at all time intervals (P = 0.001). Also, the cumulative dose of ropivacaine and the total use of fentanyl postoperatively in Group R was much higher (70 ± 10.4 vs 56 ± 8.9 µg, P = 0.02). The C-reactive protein levels were significantly lower in Group R + D (13.8 ± 1.5 vs 23.1 ± 1.2 mg/L, P = 0.001 and 16.5 ± 1.3 vs 28.5 ± 1.7 mg/L, P = 0.001, at 24 and 48 hrs, respectively). CONCLUSION: We conclude that dexamethasone can be used as a suitable adjuvant to intermittent local anesthetic infiltration after percutaneous nephrolithotomy with a nephrostomy tube for the prolongation of analgesia.