Introducing new technology safely into urological practice

Evaluation of Surgical Learning Curve Effect on Obstructive Sleep Apnea Outcomes in Upper Airway Stimulation

OBJECTIVE

An increasing number of facilities offer Upper Airway Stimulation (UAS) with varying levels of experience. The goal was to quantify whether a surgical learning curve exists in operative or sleep outcomes in UAS.

METHODS

International multi-center retrospective review of the ADHERE registry, a prospective international multi-center study collecting UAS outcomes. ADHERE registry centers with at least 20 implants and outcomes data through at least 6-month follow-up were reviewed. Cases were divided into two groups based on implant order (the first 10 or second 10 consecutive implants at a given site). Group differences were assessed using Mann-Whitney U-tests, Chi-squared tests, or Fisher's Exact tests, as appropriate. A Mann-Kendall trend test was used to detect if there was a monotonic trend in operative time. Sleep outcome equivalence between experience groups was assessed using the two one-sided tests approach.

RESULTS

Thirteen facilities met inclusion criteria, contributing 260 patients. Complication rates did not significantly differ between groups (P = .808). Operative time exhibited a significant downward trend (P < .001), with the median operative time dropping from 150 minutes for the first 10 implants to 134 minutes for the subsequent 10 implants. The decrease in AHI from baseline to 12-month follow-up was equivalent between the first and second ten (22.8 vs 21.2 events/hour, respectively, P < .001). Similarly, the first and second ten groups had equivalent ESS decreases at 6 months (2.0 vs 2.0, respectively, P < .001). ESS outcomes remained equivalent for those with data through 12-months.

CONCLUSIONS

Across the centers' first 20 implants, an approximately 11% reduction operative time was identified, however, no learning curve effect was seen for 6-month or 12-month AHI or ESS over the first twenty implants. Ongoing monitoring through the ADHERE registry will help measure the impact of evolving provider and patient specific characteristics as the number of implant centers increases.

Procedural Surgical RCTs in Daily Practice: Do Surgeons Adopt Or Is It Just a Waste of Time?

OBJECTIVE

To assess the adoption of recommendation from randomized clinical trials (RCTs) and investigate factors favoring or preventing adoption.

BACKGROUND

RCT are considered to be the cornerstone of evidence-based medicine by representing the highest level of evidence. As such, we expect RCT's recommendations to be followed rigorously in daily surgical practice.

METHODS

We performed a structured search for RCTs published in the medical and surgical literature from 2009 to 2013, allowing a minimum of 5-year follow-up to convincingly test implementation. We focused on comparative technical or procedural RCTs trials addressing the domains of general, colorectal, hepatobiliary, upper gastrointestinal and vascular surgery. In a second step we composed a survey of 29 questions among ESA members as well as collaborators from their institutions to investigate the adoption of surgical RCTs recommendation.

RESULTS

The survey based on 36 RCTs (median 5-yr citation index 85 (24-474), from 21 different countries, published in 15 high-ranked journals with a median impact factor of 3.3 (1.23-7.9) at the time of publication. Overall, less than half of the respondents (47%) appeared to adhere to the recommendations of a specific RCT within their field of expertise, even when included in formal guidelines. Adoption of a new surgical practice was favored by watching videos (46%) as well as assisting live operations (18%), while skepticism regarding the methodology of a surgical RCT (40%) appears to be the major reason to resist adoption.

CONCLUSION

In conclusion, surgical RCTs appear to have moderate impact on daily surgical practice. While RCTs are still accepted to provide the highest level of evidence, alternative methods of evaluating surgical innovations should also be explored.

Fiducial markers: can the urologist do better?

INTRODUCTION

Radiotherapy to the bladder has a risk of toxicity to pelvic structures, which can be reduced by using fiducial markers for targeting. Injectable contrast offers an alternative marker to gold seeds, which may fall out or exacerbate scarring. Combining contrast agents with tissue glue can minimize dispersion through tissue, enhancing its utility. We evaluated combinations of contrast agents and tissue glue using porcine bladder, for feasibility and utility as fiducial markers to aid image-guided radiotherapy.

METHODS

Different contrast agents (Lipiodol ultra or Urografin) were combined with different tissue glues (Histoacryl, Tisseal or Glubran2). The mixtures were endoscopically injected into porcine bladder submucosa to identify the area of interest with multiple fiducial markers. The porcine bladders were imaged within a phantom porcine pelvis using standard radiation therapy imaging modalities. The feasibility as an injectable fiducial marker and visibility of each fiducial marker on imaging were scored as binary outcomes by two proceduralists and two radiation therapists, respectively.

RESULTS

Lipiodol-glue combinations were successfully administered as multiple fiducials that were evident on CT and CBCT. Lipiodol with Histoacryl or Glubran2 was visible on kV imaging. The Lipiodol Glubran2 combination was deemed subjectively easiest to use at delivery, and a better fiducial on KV imaging.

CONCLUSION

This study demonstrates the feasibility of mixing contrast medium Lipiodol with Histoacryl or Glubran2 tissue glue, which, injected endoscopically, provides discrete and visible fiducial markers to aid image-guided radiotherapy. Although promising, further study is required to assess the durability of these markers through a course of radiotherapy.