Analgesia and sedation are usually required during extracorporeal shock wave lithotripsy. In the present study, the recovery time and effectiveness of sedation and analgesia of dexmedetomidine was compared with a midazolam/fentanyl combination in outpatient extracorporeal shock wave lithotripsy.

Forty-nine patients scheduled for outpatient extracorporeal shock wave lithotripsy were randomly assigned to two groups: a dex group (n = 25; dexmedetomidine 1 μg kg−1 loading dose followed by dexmedetomidine 0.2 μg kg−1 h−1) and a control group (n = 24; midazolam 0.05 mg kg−1 and fentanyl 1 μg kg−1). Recovery time, rescue analgesics (fentanyl 25 μg) and sedatives (midazolam 1 mg), and patients’ satisfaction rates were recorded.

The two groups were similar regarding patient characteristics and procedure-related details (P > 0.05). Recovery time was significantly prolonged in the dex group when compared with the control group (116.4 ± 39.3 vs. 50.8 ± 19.8 min, respectively, P < 0.001). The percentage of patients requiring rescue doses of fentanyl and the applied doses were significantly higher in the dex group than in the control group (96% vs. 67%, P = 0.01; and 69.0 ± 31.7 vs. 38.8 ± 42.9 μg, respectively, P = 0.007). More patients in the dex group received rescue midazolam (96% vs. 58%, P = 0.002). More patients in the control group were highly satisfied with their sedation/analgesia (83% vs. 56%, P = 0.038).

Dexmedetomidine was associated with a longer recovery time than a midazolam/fentanyl combination when used for sedation and analgesia during outpatient extracorporeal shock wave lithotripsy in this study. The incidence of rescue sedative and analgesic need was also significantly higher when dexmedetomidine was used.

Symptomatic salivary stones in the middle or proximal parotid duct have previously been treated by gland excision, which is associated with a 3–7 per cent risk to the facial nerve. Minimally invasive approaches to the management of salivary duct calculi have been devised over the past decade. Fluoroscopically guided basket retrieval, lithotripsy and intra-oral stone removal under general anaesthesia have found favour with most surgeons. Endoscopically controlled intracorporeal shock wave lithotripsy using the pneumoblastic lithotripter has been replaced by electrohydraulic lithotripsy (used in sialolith treatment).

The electrokinetic lithotripter is normally used for the treatment of lower ureteric stones, and has the benefit of minimal concomitant tissue damage. We have extended its use to the treatment of parotid duct calculi. We present initial results for its use in the treatment of a proximal parotid duct stone.

Application of the shock wave to the stone under direct vision avoided injury to the duct or to any local structure. The patient made an uneventful recovery and was asymptomatic after 18 months' follow up.

Continuous, endoscopically monitored electrokinetic lithotripsy with good irrigation gives a well illuminated field and absolute delivery of energy to the target. It avoids the side effects caused by impact of the shock wave on the parotid duct and adjacent anatomical structures, thereby making it a safer procedure.

To determine the decibel sound pressure levels generated during extracorporeal lithotripsy for salivary stones, and if such lithotriptor noise levels have the potential for acoustic trauma.

Minilith SL-1 salivary gland lithotriptor, sound level meter; five patient survey.

Decibel measurements were conducted on the lithotripter-generated sounds, using a sound level meter at specific distances from the active element. In addition, a patient survey was conducted as a cross-reference, to enable comparison of predicted results with actual human perception of sound levels.

Sound levels ranged between 68 and 80 dB during treatment sessions, for both the lithotriptor operator and the patient.

During routine use, no acoustic trauma is incurred by either the lithotriptor operator or the patient.