Werner Weber

Shock-wave lithotripsy of gallbladder stones. The first 175 patients

To substantiate the early results of extracorporeal shock-wave fragmentation of gallstones, we used this nonsurgical procedure to treat 175 patients with radiolucent gallbladder calculi. Chenodeoxycholic acid and ursodeoxycholic acid were administered as adjuvant litholytic therapy. The gallstones disintegrated in all patients except one and completely disappeared in 30 percent of all patients within 2 months after lithotripsy, in 48 percent at 2 to 4 months, in 63 percent at 4 to 8 months, in 78 percent at 8 to 12 months, and in 91 percent at 12 to 18 months. In patients with solitary stones up to 20 mm in diameter, the corresponding values were 45, 69, 78, 86, and 95 percent, respectively. Shock-wave therapy had no adverse effects except cutaneous petechiae (14 percent) and transient gross hematuria (3 percent). One third of the patients had one or more episodes of biliary colic before all the fragments disappeared. Two patients had mild pancreatitis, which necessitated endoscopic sphincterotomy in one. The patient with insufficient stone fragmentation underwent elective cholecystectomy; no additional operations were necessary. Extracorporeal shock-wave lithotripsy combined with medical therapy for stone dissolution is a safe and effective treatment in selected patients with radiolucent gallbladder calculi.

Patient Controlled Analgesia for Shock Wave Lithotripsy: The Effect of Self-Administered Alfentanil on Pain Intensity and Drug Requirement

PURPOSE Second generation lithotriptors offer immersion-free treatment and a decrease in shock wave induced pain. Pain sensations caused by advanced lithotriptors vary widely and have a significant impact on clinical management. We tested patient controlled analgesia during extracorporeal shock wave lithotripsy (ESWL) and quantified analgesic requirements by means of patient controlled analgesia during ESWL of renal stones. MATERIALS AND METHODS Patients with renal stone disease undergoing ESWL were randomized prospectively to receive an alfentanil infusion titrated by 4 different anesthesiologists not otherwise involved in the study (22 controls) or to self-administer alfentanil via a patient controlled infusion pump (22 patients). As a measure of individual pain sensitivity the detection, pain and tolerance thresholds of electrocutaneous sensitivity were determined in all patients. RESULTS Alfentanil was used more often in the patient controlled analgesia group than in the control patients (12 versus 8 required the narcotic, respectively, p = 0.226). Patients using patient controlled analgesia needed less drug (0.5 versus 2.15 mg., p = 0.005, median values), tolerated higher discharge voltages and pain intensities, needed significantly fewer shock waves to complete stone fragmentation (1,612 versus 2,105, p = 0.014) and had shorter treatment times (36.9 versus 46.2 minutes, p = 0.069). There was a significant correlation between the duration of shock wave exposure tolerated without analgesia, and pain (p = 0.0009) and tolerance (p = 0.0020) thresholds but not with regard to detection thresholds (p = 0.1400). Male patients showed significantly higher tolerance thresholds to electrocutaneous stimulation (10.2 versus 6.9 mA., p = 0.0238), which corresponded to longer analgesia-free treatment times in male versus female patients (31.7 versus 19.4 minutes, p = 0.0510). CONCLUSIONS Patient controlled analgesia increases pain tolerance, decreases narcotic requirements, simplifies ESWL as an outpatient procedure and can be used to quantify analgesic requirements during lithotripsy. Pain and tolerance thresholds of electrocutaneous sensitivity are sensitive markers of pain tolerance during lithotripsy, which may be more pronounced in male patients.

Extracorporeal Shock-Wave Lithotripsy of Gallstones Without General Anesthesia: First Clinical Experience

Excerpt Extracorporeal shock-wave lithotripsy has recently been introduced as a nonsurgical method to disintegrate gallstones (1). So far, general anesthesia has been used in patients for alleviati...

Patient controlled analgesia for extracorporeal shock wave lithotripsy of gallstones

&NA; Sixty patients undergoing shock wave lithotripsy of gallbladder stones (ESWL) were randomly assigned to receive alfentanil either by infusion controlled by the attending anesthesiologist (standard treatment group, n = 31) or by analgesia controlled by the patient (PCA group, n = 29). Patients using PCA were allowed to self‐administer 0.25 mg of alfentanil i.v. every minute as required. Data collected during treatment included the total dose of drug required, transcutaneous pCO2 values, verbal pain and sedation scores, visual analogue scale (VAS) patient satisfaction scores, and the incidence of nausea or vomiting. PCA patients used less alfentanil than the standard treatment group (PCA group: 12.8 &mgr;g/kg; standard treatment group: 44.3 &mgr;g/kg; mean values, P = 0.0001), tolerated significantly higher pain intensities and self‐administered the narcotic only to moderate levels of pain but not to pronounced analgesia. Standard treatment patients reported lower levels of pain, were more sedated (P < 0.05) and showed significantly higher transcutaneous pCO2 values. There was a trend towards a lower incidence of nausea or vomiting in PCA patients without reaching statistical significance. No significant difference with regard to patient satisfaction with pain relief could be demonstrated. Self‐administered alfentanil during ESWL of gallbladder stones provided adequate analgesia with minimal side effects and high patient satisfaction. ESWL may represent a new and useful indication for PCA.

Reply to S.A. Coleman and J.B. Davies

We read with interest the report by Schelling et al. (1992) of patient-controlled analgesia (PCA) using alfentanil during extracorporeal shock-wave lithotripsy (ESWL) of gallstones. We have developed independently this technique for patients receiving ESWL of urinary tract stones using a similar third generation spark-gap lithotripter (Philips/Dornier MFL 5000). In our unit ESWL is performed on up to 25 patients each week, mainly on an outpatient basis. The majority of patients do not require an anaesthetist in attendance and standard analgesia for the procedure is administered by the supervising surgeon. Analgesia is provided by oral diclofenac (75 mg) supplemented in two-thirds of the cases with intravenous pethidine (SO-100 mg). Approximately 8% of patients are unable to tolerate the procedure and are referred for anaesthetic care. Many of these patients view further treatment with considerable trepidation and request “to be put to sleep”. We have found PCA alfentanil to be a most successful alternative to general anaesthesia in this self-selected population for whom standard analgesia was inadequate. Results for 25 patients are as follows. Age range was 20-90 years, with a mean treatment duration of 50 min and a peak generator setting of between 24 and 30 kV. All patients received 1 mg droperidol and 0.2 mg glycopyrrolate intravenously after positioning on the table and all breathed supplementary oxygen at 4 I/min via a face mask. PCA settings were identical to those used by Schelling et al. (1992) (bolus dose 250 pg, lock-out interval 1 min, no background infusion), except in 2 frail octagenarians in whom the bolus dose was reduced to 150 pg. Transcutaneous pC0, monitoring was not available to us but no patient developed bradypnoea ( < 10 breaths/min). Blood pressure and pulsatile oxygen saturation remained satisfactory throughout. One patient suffered transient nausea on mobilisation but no patient vomited. All outpatients were discharged home within 2 h of completing treatment. PCA alfentanil consumption was higher than that reported by Schelling et al. (37.6+ 12.2 @g/kg vs. 12.8+ 9.9 Fg/kg) and approached that of their standard treatment group which received alfentanil at a rate of infusion controlled by the anaesthetist (44.3 + 28.3 fig/kg). We attribute this difference to our selected population (we were treating only the 8% of patients for whom standard analgesia was inadequate) and to their heightened preoperative anxiety. Interestingly, we noted a reduction in consumption in patients treated with PCA alfentanil on a second occasion. Patients were encouraged to abolish pain and reported lower pain scores (equivalent to O-l on the verbal rating scale employed by Schelling et al.). Sedation scores were correspondingly higher but all patients remained cooperative. In summary, PCA alfentanil has proved highly successful in these challenging patients and we would endorse fully the enthusiasm of Dr Schelling and his colleagues for this technique. In addition, we feel that in suitably selected and monitored patients this technique can be safely managed by the surgeon supervising ESWL, thus allowing the provision of optimal analgesia without the need for dedicated anaesthetic staff.