Evolution of pre-treatment stenting and local anesthesia for extracorporeal shock wave lithotripsy at a single university center

Efficacy of local subcutaneous anesthesia versus intramuscular opioid sedation in extracorporeal shockwave lithotripsy: a randomized study

PURPOSE

To evaluate the analgesic efficacy of local subcutaneous (SC) anesthesia compared with intramuscular (IM) opioid sedation during extracorporeal shockwave lithotripsy (SWL) in a randomized study.

PATIENTS AND METHODS

After informed consent was obtained, 125 patients with urolithiasis who were scheduled for SWL were included in the study. The patients in each treatment session were randomized to receive either IM meperidine (group A) or SC infiltration of 10 mL 2% lidocaine and 10 mL 0.5% bupivacaine at the area of shockwave entry (group B). Degree of pain was rated by the patient using a five-point visual analogue scale (VAS).

RESULTS

The study included 88 (70.4%) men and 37 (29.6%) women with a mean age of 47.6 ± 12.5 years and a mean body mass index (BMI) of 28.16 ± 4.67 kg/m2. Of the patients, 89, 26, and 10 received a single, two, or more than two treatment sessions, respectively (176 sessions). Maximum stone length was 10.68 ± 5.12 mm. Pretreatment stent placement was performed in 17 (13.6%) patients (28 sessions). Group A comprised 89 treatment sessions while 87 were involved in group B. Both groups were similar. Supplemental intrvenous sedation was needed in two (2.5%) and four (4.6%) sessions in groups A and B, respectively. VAS was not different between both groups (P = 0.063). Patients with pretreatment stent placement had significantly lower VAS score compared with patients without stents (P = 0.012). Sex and BMI had no impact on the VAS score.

CONCLUSIONS

Local SC anesthesia alone is effective for analgesic purposes during extracorporeal SWL. Sex, age, and BMI have no relation to analgesia requirement.

Correlation of ureteric length with anthropometric variables of surface body habitus

OBJECTIVE

To evaluate the association of variables of body habitus with direct measurements of ureteric length, as the correct choice of ureteric stent length might help to prevent complications and improve stent tolerance, and to date there are limited data correlating height or other body variables with ureteric length.

PATIENTS AND METHODS

We prospectively measured pelvi-ureteric junction to vesico-ureteric junction length in 100 patients by placing a ruled 5 F ureteric catheter. Ureteric length was then correlated with patient height, weight, body mass index, and distance from the shoulder (acromium process) to the wrist (head of the ulna; S-W), the elbow (olecranon process) to the wrist (head of the ulna), xyphoid process to umbilicus, xyphoid process to pubis (X-P), umbilicus to pubis, and anterior iliac spine to anterior iliac spine. Patients with pathology affecting the ureteric length were excluded. The results were analysed statistically using a multiple linear regression model with stepwise selection of variables, and a paired t-test.

RESULTS

The mean right and left ureteric lengths were similar (P=0.61); height (P<0.01), weight (P=0.02), X-P (P=0.01), and S-W (P=0.02) distances all correlated with ureteric length. On multivariate regression analysis, weight, height and male gender were associated with mean ureteric length. From these data a formula was constructed to predict ureteric length.

CONCLUSIONS

It is a challenge to predict ureteric length from body habitus, but height, X-P distance and S-W distance can be used to predict ureteric length.

Subjective Pain Scale and the Need for Analgesia during Shock Wave Lithotripsy

OBJECTIVE

To investigate patients' opinions on the degree of pain during shock wave lithotripsy, and the need for analgesics in patients with urinary stone.

METHODS

A prospective questionnaire study involving subjective pain assessment during and just after shock wave lithotripsy was performed in consecutive patients with uncomplicated renal or ureteral stones. The patients were given unbiased information on the analgesics prior to the procedure. Ten minutes after beginning shock wave lithotripsy, the degree of pain was rated by the patient using a 10-point visual analog scale. After the procedure, the patients were asked to complete a self-administered questionnaire. Based on the response for the questionnaire, the patients were divided as 'tolerable' or 'non-tolerable' group.

RESULTS

The results from 180 patients (males 113, females 67) with a mean age of 50.0 +/- 13.0 were analyzed. The average subjective pain score was 6.6 +/- 2.3 during the procedure, and 70 (38.9%) patients responded that they were able to tolerate the pain without analgesics. A total of 116 (64.4%) patients did not agree that analgesic should be recommended to other patients. Subjective pain score during the procedures was not affected by laterality, size of stone, level of education or socioeconomic status, but was affected by patient age (p = 0.042), sex (p = 0.012) and location of stone (p = 0.014). Right and kidney stones were significantly higher in the 'non-tolerable' group than in the 'tolerable' group (p = 0.003 and p = 0.011, respectively), and the 'non-tolerable' patient group had a significant higher pain score than the 'tolerable' group (p < 0.001).

CONCLUSIONS

Our result shows that subjective pain severity during shock wave lithotripsy is high but may be well tolerated in some patients. Our findings raise the question as to whether routine analgesics are required during newer generation shock wave lithotripsy procedures in all patients with a urinary stone.

Analgesia during extracorporeal shock wave lithotripsy using the Medstone STS lithotriptor: a randomized prospective study

OBJECTIVES

To investigate and compare the effectiveness of three analgesic protocols for pain management during extracorporeal shock wave lithotripsy (ESWL) in a prospective, randomized clinical trial.

METHODS

Seventy-four patients were randomized into three groups before ESWL; group A (n = 23) received 10 mg morphine sulfate (MS), group B (n = 25) 60 mg ketorolac tromethamine (KT), and group C (n = 26) topical 2.5% lidocaine/prilocaine gel (Emla). Each method of pain management during ESWL was assessed using a standard 10-point linear pain scale and by the requirement for supplemental analgesia during treatment. Supplemental analgesia was administered intravenously using a patient-controlled analgesic pump. The results were compared between the three groups, as were such parameters as body habitus, stone burden, stone location, number of shock waves, and the presence of ureteral stents.

RESULTS

Pain severity averaged 4.6 points on the pain scale for the three groups combined. Pain tended to be more severe in group C (5.4) than in group A (4.3) or group B (4.1); however, the differences were not statistically significant (P>0.05). The amount of supplemental analgesia was similar in all three groups. Stone burden, stone location, and number of shock waves did not influence the severity of pain or analgesic requirement during ESWL. The analgesic requirement was significantly less in patients with ureteral stents (n = 32) than in patients without (n = 42), averaging 10 mg versus 24 mg MS, respectively (P = 0.01). KT was not associated with adverse events such as bleeding. MS was more likely to cause oversedation and nausea or vomiting, necessitating naloxone and antiemetic therapy, respectively.

CONCLUSIONS

The use of KT was safe and effective for premedication before ESWL; patients receiving KT before ESWL reported lower pain scores and required less supplemental analgesia requirement than those who received MS or Emla; however, the differences were not statistically significant. Patients receiving Emla recorded the highest pain scores. Patients with ureteral stents had lower pain scores and required less supplemental analgesia.

Role of color-coded Doppler sonography in the assessment of internal ureteral stent patency

OBJECTIVE

To evaluate the role of color-coded Doppler sonography (CCDS) in the assessment of internal ureteral stent patency.

PATIENTS AND METHODS

We compared micturating cystography (MC) and CCDS in 48 patients with internal ureteral stents. Forty-five of these patients had pyelocaliectasis on renal sonography.

RESULTS

In all of the 48 patients, the distal end of the internal ureteral stent could be seen sonographically in the bladder. The color images of 30 patients showed typical flow from the distal holes of the stent. Micturating cystography demonstrated patency of the stents in 36 patients. The two procedures showed the same results in 42 of 48 patients. Six patients had no detectable flow by CCDS, but the MCs showed patency of the stents.

CONCLUSION

The CCDS is a valid noninvasive method for the assessment of internal ureteral stent patency with a sensitivity of 100%, a specificity of 83%, a positive predictive value of 67%, and a negative predictive value of 100%.

Spontaneous fracture of indwelling ureteral stents in patients treated with extracorporeal shock wave lithotripsy: two case reports

Placement of indwelling ureteral stents adjunctive to ESWL treatment has been a widespread practice. We herein present two cases of spontaneous breakage of double pigtail ureteral stents and their management. Prevention of this complication may be possible by careful examination of the stents prior to insertion, by following the instructions of manufacturers on maximum time limits and by using stent logs to keep track of patients.

Indwelling ureteral stents as definitive therapy for distal ureteral calculi

Distal ureteral calculi are a common urological problem often requiring surgical and anesthetic intervention. In a health care system with limited resources this intervention can lead to the expenditure of significant monies. Ureteral stents are often used to stabilize symptomatic patients preoperatively. Since stent placement causes passive ureteral dilation, we hypothesized that temporary placement of a ureteral catheter would facilitate spontaneous calculus passage. We prospectively studied 27 patients who presented with distal ureteral calculi less than 10 mm. large and met criteria established for surgical intervention. Self-retaining Double-J stents were placed in 10 male and 7 female patients, and left for 2 weeks using only topical anesthesia during the procedures. In the majority of the patients (83%) the calculi passed spontaneously after stent removal, obviating surgical or anesthetic intervention.

In situ extracorporeal shock wave lithotripsy for primary ureteric calculi

OBJECTIVE

To determine the efficacy of the Lithostar lithotriptor for the in situ treatment of primary ureteric stones.

METHODS

We reviewed, retrospectively, our experience with 283 patients with primary ureteric stones treated with extracorporeal shock wave lithotripsy (ESWL) using the Lithostar lithotriptor. No attempts were made to manipulate the stones. The majority of the patients were treated using only intravenous analgesia. Auxiliary measures were used in 84 patients (29.6%). There were 112 patients (39.6%) with upper, 53 (18.7%) with middle, and 118 (41.7%) with lower ureteric stones.

RESULTS

A single ESWL session was needed for 200 patients (70.6%), two for 49 patients (17.3%), and more than two sessions for 34 patients (12%). Of the 248 patients who had adequate follow-up, 220 (88.7%) were stone free, 14 (5.65%) had some residual stone, while 14 (5.65%) patients failed to respond to the treatment. Patients' gender and body weight influenced the treatment and the clearance rate numerically without any statistical significance. The stone site was the most significant factor influencing the final result. Stones larger than 10 mm and the presence of hydronephrosis adversely affected the treatment.

CONCLUSIONS

In situ ESWL of ureteral stones with the Lithostar device is a convenient and efficient method of treating calculi within the whole length of the ureter without the need for any manipulation.

In vitro calcium oxalate lithotripsy: comparison of Dornier HM3 and Siemens Lithostar

In vitro lithotripsy of round calcium oxalate stones retrieved from a patient at pyelolithotomy was used to compare the Dornier HM3 and Siemens Lithostar lithotripters. Similar stones were subjected to the same number of shock waves at similar kilovoltages and shock wave frequencies, and percent fragmentation was calculated. The numbers of shock waves required to fragment similar stones completely at the same kilovoltages were determined. Using 50 shock waves at less than 16 kV, the Siemens Lithostar produced little fragmentation of like stones, while at 16 kV and above, the Lithostar and the Dornier HM3 yielded similar stone fragmentation. The number of shock waves required to obtain complete fragmentation was similar for the HM3 and the Lithostar at greater than 16 kV. Using energy levels less than 16 kV, the HM3 needed markedly fewer shock waves to achieve fragmentation, although complete fragmentation could be accomplished with the Lithostar.

Stent use with extracorporeal shock wave lithotripsy

Since the advantages of using ureteral stents in conjunction with extracorporeal shock wave lithotripsy were first recognized, the growing demand for outpatient stone treatment has made stent use much more frequent. However, prophylactic stent placement must be judicious to maximize success and minimize associated morbidity. Recent controlled retrospective studies and randomized trials showed that ureteral stenting does not increase the stone-free rate or reduce the complication rate for stones less than 2 cm in size, yet in such cases, there are increased morbidities such as urinary urgency, frequency, stent migration, and encrustation. However, in patients with stones larger than 2 cm, Type C4 staghorn calculi, or stones associated with a solitary kidney, prophylactic stent placement may reduce the complication rates arising from these larger stone burdens. Finally, ureteral stenting may be helpful for stone localization or manipulation.

Anesthesia and complications of extracorporeal shock wave lithotripsy of urinary calculi

The techniques of anesthesia for extracorporeal shock wave lithotripsy of urinary calculi and the associated complications in 600 treatments with the second generation lithotriptor Siemens Lithostar were studied. General anesthesia was used in 17 treatments (2.8%) and epidural anesthesia was applied in 73 (12%), primarily in children and patients in need of simultaneous surgical auxiliary procedures. A total of 510 treatments (85%) was performed with a combination of local infiltration anesthesia and supplementary intravenous opiates. In 65% of the cases only 2 injections of opiates were sufficient for pain relief. There were no complications in 394 treatments (77%) and minor complications, such as arrhythmia (9.2%) and nausea/vomiting (7.6%), were easily treated. Respiratory depression was observed in 10 cases (2%) and this potentially dangerous complication was associated with simultaneous administration of opiates and midazolam. Only 9 treatments (1.8%) had to be terminated due to complications. It is concluded that most treatments of urinary calculi with this second generation extracorporeal shock wave lithotriptor can be performed with local infiltration anesthesia combined with supplementary short-acting opiates intravenously for pain relief and sedation. When administering supplementary midazolam for sedation the risk of respiratory depression should be considered.

Ureteral stenting with extracorporeal shock-wave lithotripsy

We reviewed the results of ureteral stent use with extracorporeal shock-wave lithotripsy (ESWL) in 3,096 patients with renal calculi less than 3 cm in diameter. The 2,595 patients with indwelling ureteral stents required lower total power (shocks x voltage) and less radiation and had a lower secondary procedure rate but a higher retreatment rate than the 501 patients without stents. However, the only statistically significant difference was in the average radiation dose in patients with or without stents and single stones no larger than 10 mm (16 vs. 18 rad). The hospital stay was one day or less in 98 percent of the patients in both groups. With an 80 percent follow-up rate at three months indwelling ureteral stents were associated with a higher stone-free rate in patients with a single stone but a lower stone-free rate in patients with multiple stones, compared with those treated without a stent. An indwelling ureteral stent may result in urinary frequency and bladder discomfort in some patients, and with no statistical difference in the results with or without a ureteral stent it is questionable whether or not the high use of an indwelling ureteral stent is justified in patients admitted for one day or less.

Local anesthesia for extracorporeal shock wave lithotripsy: a study comparing eutetic mixture of local anesthetics cream and lidocaine infiltration

A study of the anesthetic efficacy of a eutetic mixture of local anesthetics (EMLA cream) versus lidocaine infiltration in extracorporeal shock wave lithotripsy (ESWL) was done. A total of 46 patients had 30 gm. of EMLA cream applied to the skin over the kidney and 45 had subcutaneous infiltration anesthesia with 20 ml. 1% lidocaine with epinephrine. All patients received an intravenous dose of morphine just before ESWL. The patients were comparable with regard to age, sex, weight, morphine dosage, number of shock waves given and duration of treatment. Median pain score and the amount of supplementary analgesics were not significantly different between the 2 groups. There were no significant differences between the groups with regard to post-ESWL skin changes. Therefore, EMLA cream can be recommended for ESWL provided it is applied correctly.