Dexmedetomidine in combination with morphine PCA provides superior analgesia for shockwave lithotripsy

Abstract

Purpose: To compare the analgesic effects of dexmedetomidine/morphine with those of tramadol/midazolam in patients undergoing extracorporeal shockwave lithotripsy (ESWL) for urinary calculi. Methods: Sixty patients were randomized to receive either dexmedetomidine 1 μg·kg-1 iv followed by 0.5 μg·kg-1·hr-1 infusion together with morphine patient-controlled analgesia [(PCA); 2 mg bolus, five minutes lockout, 2 mg·hr-1 infusion; (Group DEX)], or tramadol 1.5 mg·kg-1 pre-mixed with midazolam 30 μg·kg-1 iv followed by tramadol PCA [20 mg bolus, five minute lockout, 20 mg·hr-1 infusion; (Group TRA ]. Pain was assessed at baseline and every 15 min thereafter. Patients' and urologist's satisfaction with analgesia and sedation were determined on a seven-point scale ranging from 1 (extremely dissatisfied) to 7 (extremely satisfied). Patient's discharge time was also documented. Results: Visual analogue scale scores over time were consistently lower in Group DEX compared with Group TRA (P = 0.001). Patients' satisfaction with analgesia (5 ± 1 vs 4 ± 2, P = 0.012) and with sedation (6 ± 1 vs 5 ± 1, P = 0.020), and urologist's satisfaction (6 ± 1 vs 4 ± 2, P = 0.001) were all higher amongst Group DEX patients compared with Group TRA. There was no difference between discharge times of patients in Group DEX compared with those in Group TRA [85 (60,115) min vs 65 (40,95) min, P = 0.069]. Conclusion: Dexmedetomidine in combination with morphine PCA provided better analgesia for ESWL and was associated with higher patients' and urologist's satisfaction when compared with a tramadol/midazolam PCA combination.