Initial Clinical Experience With a Novel Robotically Assisted Platform for Combined Mini-Percutaneous Nephrolithotomy and Flexible Ureteroscopic Lithotripsy.

PURPOSE: We sought to evaluate the technical feasibility of performing a combined robotically assisted mini-percutaneous nephrolithotomy (PCNL) and flexible ureteroscopy (URS) procedure by a single urologist using the MONARCH Platform, Urology (Johnson & Johnson MedTech, Redwood City, California). MATERIAL AND METHODS: In this prospective, first-in-human clinical trial, 13 patients underwent robotically-assisted PCNL for renal calculi at the University of California-Irvine, Department of Urology. Successful completion of the procedure was assessed as the primary endpoint. Postoperative adverse events were monitored for 30 days following the completion of the procedure. Stone ablation efficiency was evaluated on postoperative day 30 with low-dose 2-3 mm slice CT scans. Patients were classified according to the maximum length of their residual stone fragments as either absolute stone-free (Grade A), < 2 mm remnants (Grade B), or 2.1-4.0 mm remnants (Grade C). RESULTS: The combined robotic mini-PCNL and URS procedure was successfully completed in 12 of 13 procedures. No robotic device-related adverse events occurred. Preoperative stone burden was quantified by both maximum linear measurement (median 32.8 mm) as well as by CT-based volume (median 1645.9 mm3). Using the unique robotically assisted targeting system, percutaneous access was gained directly through the center of the renal papilla in a single pass in all cases. Median operative time was 187 minutes (range: 83-383 minutes). On postoperative day 30, a 98.7% (range: 72.9%-100.0%) volume reduction was achieved, with 5 Grade A (38.5%), 1 Grade B (7.7%), and 2 Grade C (15.4%). Three patients experienced complications (2 grade 1 and one grade 2 Clavien-Dindo). CONCLUSIONS: Our preliminary investigation demonstrates the safety, efficacy, and feasibility of a unique robotic-assisted combined mini-PCNL and URS platform.

Comparison of electromagnetic guided imagery to standard confirmatory methods for ascertaining nasogastric tube placement in children.

PURPOSE: Evaluate the accuracy of an electromagnetic device (EMD) guided nasogastric tube (NGT) placement compared with standard confirmation methods. A secondary aim was to determine if EMD guided NGT placement would avert potential pulmonary misplacements of the tube. DESIGN AND METHODS: Pediatric Intensive Care Unit (PICU) patients were enrolled if they had an NGT order during the study period of April 2014 through December 2016. Patients were included if they were one through 18 years of age. An EMD trained nurse inserted the NGT using EMD guidance. An insertion questionnaire, confirming if the nurse determined the NGT to be gastric per EMD, was completed immediately after NGT placement and before confirmation via either pH testing or radiographic imaging. RESULTS: Forty-five patients were enrolled in the study. Nurses reported, based on EMD, that 86.7% (n = 39) of placements were gastric. Overall agreement between EMD guided tube placement and pH testing was 58% (n = 26). The marginal distribution was significantly different between the two methods (p = .0029). When compared to radiographic confirmation, sensitivity of the pH method was 32% (95% confidence interval [CI]: 17%-51%) compared with 85% (95% CI 69%-95%) for the EMD method. CONCLUSIONS: EMD guidance was superior to pH testing when compared with radiographic confirmation of nasogastric tube placement in children. PRACTICE IMPLICATIONS: EMD guided NGT placement is a potentially viable method for confirming nasogastric tube placement in children when done by appropriately trained clinicians. More research on EMD guided NGT placement in children is needed before any practice recommendation can be made.

Novel EM Guided Endovascular Instrumentation for In Situ Endograft Fenestration.

Objective: This work aims at providing novel endovascular instrumentation to overcome current technical limitations of in situ endograft fenestration including challenges in targeting the fenestration site under fluoroscopic control and supplying mechanical support during endograft perforation. Technology: Novel electromagnetically trackable instruments were developed to facilitate the navigation of the fenestration device and its stabilization at the target site. In vitro trials were performed to preliminary evaluate the proposed instrumentation for the antegrade in situ fenestration of an aortic endograft, using a laser guidewire designed ad hoc and the sharp end of a commercial endovascular guidewire. Results: In situ fenestration was successfully performed in 22 trials. A total of two laser tools were employed since an over bending of laser guidewire tip, due to its manufacturing, caused the damage of the sensor in the first device used. Conclusions: Preliminary in vitro trials demonstrate the feasibility of the proposed instrumentation which could widespread the procedure for in situ fenestration. The results obtained should be validated performing animal studies. Clinical Impact: The proposed instrumentation has the potential to expand indications for standard endovascular aneurysm repair to cases of acute syndromes.

Cortrak® duodenal tube placements: A solution for more patients? A preliminary survey to the introduction of electromagnetic-guided placement of naso-duodenal feeding tubes.

RATIONALE: The Cortrak® feeding tube, an electromagnetic (EM) guided feeding tube which is placed by a trained nurse at the patient's bedside, is reported to be a safe, patient friendly and cost effective answer to the disadvantages of endoscopic placement of naso-duodenal feeding tubes. However, this procedure requires a learning curve and regular practice. This study aims to evaluate whether introducing Cortrak® feeding tube placement would be profitable in a tertiary referral academic hospital. METHODS: We re-evaluated all endoscopically placed post-pyloric feeding tubes in the years 2012-2013. Taking into consideration training for nurses to learn how to place Cortrak® feeding tubes, strict inclusion criteria were formulated for the initial retrospective analysis: age 18 years or older, normal GI anatomy and non-ICU admitted patients. As a secondary analysis we also evaluated ICU patients (age >18 and normal upper GI tract). RESULTS: Patient records of 487 duodenal feeding tube placements in 331 patients were evaluated; 125 non-ICU placements (in 90 patients) and 84 ICU placements (in 75 ICU patients) fulfilled the inclusion criteria. Main reasons for exclusion were: abnormalities of the upper GI tract (n = 176) and endoscopy for diagnostic reasons (n = 74). Main indications for placements were gastroparesis (37%) or insufficient food intake (20%). For secondary analysis, 84 placements in 75 ICU patients were re-evaluated, with main indication gastroparesis (62%). CONCLUSION: In our hospital, at least one quarter of the duodenal tube placements would qualify for Cortrak® placement in the initial phase. Once routine has been built up and also ICU patients could be considered, half or more patients requiring a naso-duodenal feeding tube would qualify for Cortrak® placement, adding up to 3 placements per week. The findings of this study may help to decide on the profitability of introducing this method in our own hospital. The next step will be to perform a cost-benefit analysis to study whether implementing Cortrak® in practice is cost-effective and feasible.

Feeding Tube Insertion and Placement Confirmation Using Electromagnetic Guidance: A Team Review.

BACKGROUND: Challenges for bedside placement of small-bore feeding tube (SBFT) include iatrogenic injury, multiple exposures to x-rays, and prolonged placement times. In 2011, the study facility began a feeding tube placement team (FTPT) using the CORTRAK system (CS) in the adult intensive care unit (ICU) and medical-surgical populations. In 2013, a protocol was implemented using the CS to determine final SBFT location. METHODS: Serial retrospective reviews were done of patients with SBFT placement by the FTPT during July 2011-December 2012 and 2015. Measures included pulmonary deviation, tube location, placement agreement beyond chance for CS tracing and confirmation radiography (CR), x-ray frequency, and placement time intervals. RESULTS: A total of 6290 SBFT placements were completed for 4239 patients. First-attempt SBFT locations were 12.78% gastric, 13.39% first through fourth portion of duodenum, and 73.83% ligament of Treitz/jejunum, with zero placements in esophagus or lung. In 2015, staff avoided 68 lung placements by recognizing proximal pulmonary deviation. X-ray preprotocol vs protocol (mean [SD]: 1.02 [0.15] vs 0.26 [0.44]) resulted in 74% x-ray reduction and cost avoidance of $346,000. Time intervals (mean [SD]; N = 6290) were 14.90 (12.74) minutes for insertion, 46.04 (13.80) minutes for placement event, and 3.85 (2.23) hours for consult conclusion. Agreement for n = 1692 placements was 85.28%, with k score of 0.622 (95% confidence limit: 0.582, 0.661; P = .0005). CONCLUSIONS: Team management of SBFT placement using the CS optimizes patient safety, standardizes practice, and decreases cost. Using the CS to determine final SBFT location is a safe alternative to CR.

Pediatric hydrocephalus: systematic literature review and evidence-based guidelines. Part 3: Endoscopic computer-assisted electromagnetic navigation and ultrasonography as technical adjuvants for shunt placement.

OBJECT: This systematic review was undertaken to answer the following question: Do technical adjuvants such as ventricular endoscopic placement, computer-assisted electromagnetic guidance, or ultrasound guidance improve ventricular shunt function and survival? METHODS: The US National Library of Medicine PubMed/MEDLINE database and the Cochrane Database of Systematic Reviews were queried using MeSH headings and key words specifically chosen to identify published articles detailing the use of cerebrospinal fluid shunts for the treatment of pediatric hydrocephalus. Articles meeting specific criteria that had been delineated a priori were then examined, and data were abstracted and compiled in evidentiary tables. These data were then analyzed by the Pediatric Hydrocephalus Systematic Review and Evidence-Based Guidelines Task Force to consider evidence-based treatment recommendations. RESULTS: The search yielded 163 abstracts, which were screened for potential relevance to the application of technical adjuvants in shunt placement. Fourteen articles were selected for full-text review. One additional article was selected during a review of literature citations. Eight of these articles were included in the final recommendations concerning the use of endoscopy, ultrasonography, and electromagnetic image guidance during shunt placement, whereas the remaining articles were excluded due to poor evidence or lack of relevance. The evidence included 1 Class I, 1 Class II, and 6 Class III papers. An evidentiary table of relevant articles was created. CONCLUSIONS/RECOMMENDATION: There is insufficient evidence to recommend the use of endoscopic guidance for routine ventricular catheter placement. STRENGTH OF RECOMMENDATION: Level I, high degree of clinical certainty. RECOMMENDATION: The routine use of ultrasound-assisted catheter placement is an option. STRENGTH OF RECOMMENDATION: Level III, unclear clinical certainty. RECOMMENDATION: The routine use of computer-assisted electromagnetic (EM) navigation is an option. STRENGTH OF RECOMMENDATION: Level III, unclear clinical certainty.

Electromagnetic navigation in minimally invasive spine surgery: results of a cadaveric study to evaluate percutaneous pedicle screw insertion.

BACKGROUND: This cadaveric study compared efficacy and safety of an electromagnetic (EM) guidance system versus conventional fluoroscopy for percutaneous pedicle screw fixation. As percutaneous pedicle screw fixation becomes increasingly common in spinal surgery, intraoperative imaging systems that maximize efficiency while minimizing radiation exposure and inaccurate trajectories will be progressively more important. Published studies have validated the safety of percutaneous screw fixation using conventional fluoroscopic guidance and frameless optical stereotaxy, though EM guidance systems have not been evaluated for percutaneous placement in the lumbosacral spine. The aim of the study was to evaluate the clinical applicability of an EM system for minimally invasive spine fusion in the lumbosacral spine. METHODS: Five human cadaveric specimens underwent bilateral lumbosacral percutaneous screw fixation from L1 to S1 using conventional anteroposterior (AP) and lateral fluoroscopic techniques on one side and 2-dimesional (2D) EM guidance on each matching side. Intraoperative efficiency was evaluated, and pedicle, vertebral, and critical breach rates were assessed on postoperative computed tomography (CT). RESULTS: Overall mean fluoroscopy time per screw was 58.9 ± 44.7 seconds for conventional fluoroscopy compared to 27.4 ± 13.5 seconds for electromagnetic guidance (P = .0003). Pedicle, vertebral, and critical breach rates for the L1-S1 were 32.1%, 10.7%, and 25.0% for conventional fluoroscopy and 42.8%, 10.7%, and 14.1% for electromagnetic guidance (difference not statistically significant [ns]). In comparing critical breaches in the lumbar spine (L1-L5), there was a significant difference between 2-D EM guidance (0) and CF guidance (6) (P = .02). CONCLUSIONS: Two-dimensional EM navigation provides a modality for lumbosacral percutaneous pedicle screw fixation that is more efficient and safer than conventional fluoroscopy. This data provides a foundation for further clinical trials of this technology. LEVEL OF EVIDENCE: Level 5 - Bench Research.