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Introduction: Percutaneous nephrolithotomy (PCNL) is the gold standard treatment for patients with a large stone burden. There are a variety of methods to teach this important endourologic procedur...

Routine preoperative electrocardiogram (ECG) before shockwave lithotripsy (SWL) is frequently performed despite recommendations against its use in asymptomatic patients undergoing low-risk surgical procedures. This study assesses whether routine preoperative ECG before SWL is useful in patients at low risk for cardiac complications.A retrospective study of SWL at our center (2003-2013) reviewed all cardiac-related preoperative cancellations, intraoperative complications, postoperative admissions, and emergency department presentations in patients at low risk for cardiac complications. Patients received SWL with sedation and continuous five-lead ECG monitoring.Of 30,892 referrals, preoperative ECG triggered 13 (0.04%) cancelations in low-risk patients (1 with new atrial fibrillation and 12 with ischemia/previous infarction). Of these patients, 1 had a subsequent abnormal cardiac work-up and 11 underwent uncomplicated SWL without cardiac intervention (2 had unknown history). Of 27,722 treatments, 5 (0.02%) were stopped prematurely in low-risk patients because of arrhythmia (3 had normal preoperative ECG, 1 had abnormal ECG, and 1 did not complete ECG). Three patients developed an arrhythmia with sedation and 2 patients were admitted postoperatively because of cardiac complications (1 for atrial fibrillation and 1 for hypertension), of whom all had normal preoperative ECG. No patients presented to our emergency department with cardiac complications after SWL.In patients at low risk for cardiac complications, preoperative ECG triggered very few cancellations and did not predict early termination of treatment or cardiac complications after SWL. These findings suggest that in low-risk patients, routine preoperative ECG has little effect on treatment or complication rate and should be omitted.

Flexible ureteroscopy (fURS) is a one-person surgical technique, limiting trainees' ability to practice intra-operatively. Although well-suited for simulation training, few existing fURS simulators reproduce accurate, complex renal collecting system anatomies. We developed an anatomically accurate fURS simulator using 3D reconstructions of CT urograms and 3D printing technology to address this need.Patient-specific CT urograms were used to create 3D reconstructions of the renal collecting system using SlicerTM. 3D models were modified using BlenderTM. Hollow elastomer kidney models were created using an Objet 3DTM printer. To test and evaluate the new fURS simulator, 25 volunteers were recruited (5 novices, 13 residents, 7 urologists). Participants were asked to explore the model with fURS and were evaluated on their ability to deduce its 3D anatomy, their ability to navigate to prespecified calyces, and their time to task completion. Furthermore, participants were asked to compare the anatomical model to existing fURS benchtop models (Cook MedicalTM and Limb and ThingsTM) on several criteria, including internal visualization; tactile feedback; and overall functional and teaching fidelity, in a survey.We were able to create a fURS simulator that accurately replicates anatomically complex renal collecting systems. In exploring the model, we noted that unlike staff urologists, novices and residents often completely missed lower pole calyces. A survey comparison between our simulator and comparable benchtop simulators revealed consistently better ratings of our simulator on all criteria (p0.05).We were able to successfully create an anatomically accurate fURS simulator that provides a more realistic scoping experience. Preliminary testing revealed that trainees will benefit from this simulator particularly with respect to learning how to navigate challenging collecting systems.