Role of inversion therapy and diuretics during extracorporeal shockwave lithotripsy to improve clearance rate of lower Calyceal stones

Objectives: To combine Trendenlenburg Positioning of Patient and Intra Procedural Forced Diuresis during Shock Wave Lithotripsy to improve stone clearance rate for Lower Calyceal Stones. To compare the results obtained with that of Standard Supine Shock Wave Lithotripsy for Lower Calyceal Stones. Methods: A prospective study was done in Institute of Urology, MMC, Chennai between February 2015 to February 2016. All patients presented with isolated lowerpole renal calculi of size between 7-20mm were registered. Total number of patients included are 132. Among them 33 patients refused to participate in the study and 14 patients who failed to follow up are excluded. All patients selected were allotted randomly in to two groups. Group A, comprising 62 patients who underwent ESWL with inversion therapy and intra-procedural diuresis Group B, comprising 56 patients, who underwent standard Supine ESWL and the data including number of sessions, success rate, and complications are all recorded and analysed. Results: Both groups were comparable in terms of Demography (age, sex) and in terms of Stone Characteristics. Based on number of sessions for ESWL, there is a significant increase in number of third session required in Group B, when compared to Group A. (P value 0.044) Regarding treatment success, both Stone Free Rate and Insignificant Residual Fragments are significantly higher in Group A, from first follow up itself, which increased steadily up to 12 weeks. (P value 0.04). Overall success rate achieved is 74.6%. And Treatment success rate achieved with the study group (Group A) is 82.3%, when compared to 66.1% achieved with the control group. There is a significant difference between the two groups in terms of treatment success. (p value 0.044) In both groups the average stone size and stone density as measured by stone attenuation value correlates significantly. Regarding complications there is no significant difference exists between the two Groups. Among the complications, colic is the most common, followed closely by LUTS and hematuria, then steinstrasse and fever in the order. Conclusion: Combination of Inversion with Intra Procedural Forced Diuresissignificantly improves the Stone Clearance Rate of Lower Calyceal Stones during Extra Corporeal Shock Wave lithotripsy. Though the results obtained are not as equivalent to that of Percutaneous Nephrolithotomy, ESWL with this combination of inversion with Forced Diuresis can be preferred for its specific advantages like Outpatient procedure, Non invasive intervention, No need for higher an aesthesia, No added cost and Can be repeated with least morbidity