Use of ultra-low dose computed tomography versus abdominal plain film for assessment of stone-free rates after shock-wave lithotripsy: implications on emergency room visits, surgical procedures, and cost-effectiveness.

The aims of this investigation were: (1) to compare residual stone-fragment (RSF) detection rates of ultra-low dose computed tomography (ULD-CT) and abdominal plain film (KUB) in urolithiasis patients undergoing shock-wave lithotripsy (SWL), and (2) to evaluate the downstream sequelae of utilizing these two disparate imaging pathways of differing diagnostic fidelity. A retrospective chart-review of patients undergoing SWL at two high-volume surgical centers was undertaken (2013-2016). RSF diagnostic rates of ULD-CT and KUB were assessed, and the impact of imaging modality used on subsequent emergency room (ER) visits, unplanned procedures, and cost-effectiveness was investigated. Adjusted analyses examined association between imaging modality used and outcomes, and Markov decision-tree analysis was performed to identify a cost advantageous scenario for ULD-CT over KUB. Of 417 patients studied, 57 (13.7%) underwent ULD-CT while the remaining 360 underwent KUB. The RSF rates were 36.8% and 22.8% in the ULD-CT and KUB groups, respectively (p = 0.019). A 5.6% and 18% of the patients deemed stone-free on ULD-CT and KUB, respectively, returned to the ER (p = 0.040). Similarly, 2.8% and 15.1% needed an unplanned surgery (p = 0.027). These findings were confirmed on multivariable analyses, Odds ratios CT-ULD versus KUB: 0.19 and 0.10, respectively, p < 0.05. With regards to cost-effectiveness, at low ULD-CT charges, the ULD-CT follow-up pathway was economically more favorable, but with increasing ULD-CT charges, the KUB follow-up pathway superseded. ULD-CT seems to provide a more 'true' estimate of stone-free status, and in consequence mitigates unwanted emergency and operating room visits by reducing untimely stent removals and false patient reassurances. Further, at low ULD-CT costs, it may also be economically more favorable.

Prospective assessment of positioning-related pain in robotic urologic surgery.

This was a prospective study to assess positioning-related pain in 20 awake volunteers in the dorsal lithotomy (DL) and lateral decubitus (LD) positions. Each volunteer was put through the series of discrete, sequential steps used to achieve a final position; each step had two options. The Wong-Baker scale (WB) was used to rate pain for each option and the preferred option and ad lib comments were recorded. We found that awake volunteers could clearly and immediately distinguish differences in pain levels between position options. For the DL position, volunteers favored having the arms slightly flexed and pronated as opposed to being straight and supinated reflected by statistically less painful WB scores and option preference. Volunteers preferred having the neck flexed as opposed to being flat. For the LD position, volunteers reported statistically lower pain scores and preference for a foam roll for axilla support as opposed to a rolled blanket, the table flexed without the kidney rest as opposed to a raised kidney rest, and the over arm board as oppose to stacked blankets for contralateral arm support. Ad lib comments from the volunteers supported the above findings. To our knowledge, ours is the first study to demonstrate objective preferences for variations in surgical positioning using awake volunteers. This exercise with awake volunteers resulted in immediate changes in positioning for real robotic surgery patients in our practice.