Editing CUA: Ureteral Calculi (2015) (section)

== Optimizing treatment outcomes ==

* '''SWL coupling'''
** Ensure proper patient coupling to reduce air bubbles in the SWL blast path, particularly near the centre of the path
** Adequate anesthesia and analgesia prevent patient movement and “decoupling” during treatment
* '''SWL targeting'''
** '''Should occur at regular intervals throughout the treatment'''
** Can be done through fluoroscopy or ultrasound
** Compression belts may help reduce renal (and ureteric) excursion with treatment
* '''SWL energy'''
** Should be maximized during treatment in order to maximize stone comminution. This is particularly true for mid and distal ureteral stones, where the renal parenchyma is not included in the blast path and thus the risk of renal injury is negligible. However, '''particularly for upper ureteric stones, SWL energy should be increased gradually, rather than beginning at maximum energy to reduce renal injury.'''
** '''Renal injury is reduced by inducing renal vasoconstriction, which is protective in reducing the rate of renal hematomas.'''
* '''SWL rate'''
** '''Optimal treatment rate is not clear'''; studies suggest that '''SWL at 60-90 shocks/min leads to better fragmentation than 120 shocks/min, particularly for larger stones.'''
*** '''Patients with upper ureteric stones >1cm, or stones that have failed prior treatment, should be treated with a SWL rate < 120 shocks/min'''
* '''SWL number of shocks'''
** The adequate '''number of shocks''' varies based on recommendations from the specific SWL machine manufacturers, but '''generally ranges from 2000-4000 shocks for ureteric stones'''
* '''Optimal time interval between SWL treatments is unclear, but can be as short as within 2 days for mid and distal ureteric stones.'''
** >2 treatments to the same ureteric stone have little incremental benefit and URS should be considered 
* '''Alpha blockers,''' in particular tamsulosin, '''should be prescribed after SWL for ureteral stones''' to improve treatment success rates
* '''Ureteral stents'''
** '''Does not improve stone-free rates''' (actually impede the passage of fragments resulting in lower stone free rates), '''reduce risk of steinstrasse, or reduce risk of infection following SWL'''
** '''Should be used prior to SWL to treat obstruction, acute kidney injury, intolerable pain, sepsis, and in those with a solitary kidney.'''
*** '''If previously inserted for sepsis, a course of antibiotics should be given prior to SWL''' and the patient should not be exhibiting signs of sepsis at the time of treatment. '''[2015 CUA Abx prophylaxis guidelines recommend pre-operative prophylaxis for ESWL in high-risk patients]'''