Surface Modification and Metal Printing Using Atmospheric Pressure Plasma

Non-thermal atmospheric plasma sources are at the centre of a growing new field of research that promises significant benefits in areas ranging from catalysis to medicine. The main value of atmospheric pressure sources lie in their ability to generate highly energetic and reactive species under near-ambient conditions. This characteristic makes atmospheric plasma an appealing alternative to well-established vacuum plasma processes. In this study, radio frequency atmospheric pressure plasma sources are used for modification of metal oxide surfaces and direct metal deposition. In atmospheric pressure plasma afterglow, plasma electrons are shown to be capable of reducing Cu2O films, this is proven by applying an external electric field to collect or to retard plasma electrons and observing the evolution of the oxide film. Using a micro-plasma jet, Cu2O and SnO2 are demonstrated to be completely reduced to their parent metals when exposed to helium plasma. A reducing plasma is required to induce partial reduction in TiO2, WO3 and ZnO, generating oxygen deficiencies. Oxygen deficient TiO2, also known as black titania is a well-known defective metal oxide photocatalyst. In this work, a facile method for producing black titania is developed using reducing plasma jets. This method improves photocatalyic efficiencies of nano-porous anatase up to sixfold while dispensing the need for vacuum or high pressure equipment. Deposition of conductive metals is a topic of ongoing research, with an aim to develop techniques and precursors that can enable printing of electrical circuits onto unconventional substrates. In this work, a novel technique for metal printing using plasma jets is developed. The method developed in this work enables single-step deposition of conductors from lowcost metal salt based precursors. Using aerosolized CuSO4 in the plasma jet stream, it is shown that metallic traces can be deposited on a large variety surfaces with fine spatial control

Hemodynamic responses and upper airway morbidity following tracheal intubation in patients with hypertension: Conventional laryngoscopy versus an intubating laryngeal mask airway

OBJECTIVES: We compared hemodynamic responses and upper airway morbidity following tracheal intubation via conventional laryngoscopy or intubating laryngeal mask airway in hypertensive patients. METHODS: Forty-two hypertensive patients received a conventional laryngoscopy or were intubated with a intubating laryngeal mask airway. Anesthesia was induced with propofol, fentanyl, and cis-atracurium. Measurements of systolic and diastolic blood pressures, heart rate, rate pressure product, and ST segment changes were made at baseline, preintubation, and every minute for the first 5 min following intubation. The number of intubation attempts, the duration of intubation, and airway complications were recorded. RESULTS: The intubation time was shorter in the conventional laryngoscopy group than in the intubating laryngeal mask airway group (16.33 ± 10.8 vs. 43.04±19.8 s, respectively) (p<0.001). The systolic and diastolic blood pressures in the intubating laryngeal mask airway group were higher than those in the conventional laryngoscopy group at 1 and 2 min following intubation (p<0.05). The rate pressure product values (heart rate x systolic blood pressure) at 1 and 2 min following intubation in the intubating laryngeal mask airway group (15970.90 ± 3750 and 13936.76 ± 2729, respectively) were higher than those in the conventional laryngoscopy group (13237.61 ± 3413 and 11937.52 ± 3160, respectively) (p<0.05). There were no differences in ST depression or elevation between the groups. The maximum ST changes compared with baseline values were not significant between the groups (conventional laryngoscopy group: 0.328 mm versus intubating laryngeal mask airway group: 0.357 mm; p = 0.754). The number and type of airway complications were similar between the groups. CONCLUSION: The intense and repeated oropharyngeal and tracheal stimulation resulting from intubating laryngeal mask airway induces greater pressor responses than does stimulation resulting from conventional laryngoscopy in hypertensive patients. As ST changes and upper airway morbidity are similar between the two techniques, conventional laryngoscopy, which is rapid and safe to perform, may be preferred in hypertensive patients with normal airways

Rapid single step atmospheric pressure plasma jet deposition of a SERS active surface

A helium gas atmospheric pressure plasma jet (APPJ) is used to prepare a silver-based SERS substrate. The Raman enhancement from substrates created using APPJ compares well with two commercially available silver-based SERS substrates and an in-house prepared physical deposition of pre-synthesised silver nanoparticles. An aqueous solution of rudimentary silver salt was required as an ink to deposit zero valent silver in a single step with no post processing. An array of 16 × 16 silver ‘islands’ are printed on borosilicate glass, each island taking 5 seconds to print with a power of < 14 W to sustain the plasma. The SERS response was assessed using 4-mercaptobenzoic acid and rhodamine 6G as model analytes, with a calculated detection limit of 1 × 10−6 M. Also demonstrated is the removal of analyte from the surface after Raman measurement by exposure to helium APPJ doped with oxygen followed by hydrogen to restore zero baseline. This regeneration takes less than 10 seconds and allows for replicate measurements using the same SERS substrate

Ureteroscopy in pregnant women with complicated colic pain: Is there any risk of premature labor?

Objective: Clinical presentation of ureteral stones during pregnancy is generally with renal colic pain. The aim of this study is to present our experience in the management of renal colic during pregnancy in emergency settings. Materials and methods: 208 pregnant patients who presented to emergency department with renal colic pain and underwent ureteroscopy (URS) due to failed conservative therapy were enrolled in the study. Urinary tract stones were diagnosed either with ultrasound (US) examination or during URS. Laser lithotripsy and double J (DJ) stent placement were routinely done in all patients with ureteral stones. The incidence of infective complications and premature uterine contractions (PUC) due to URS were compared. Results: No stone was identified in 36.1% (n = 75) of patients with using US and diagnostic URS. Of the remaining 133 patients, 30 (22.6%) had no stone at US but stones were diagnosed during diagnostic URS. The type of anesthesia had no significant effect on PUC. An increased risk of sepsis and PUC was found in patients with fever at the initial presentation. Interestingly, PUC was more frequent in patients with lower serum magnesium levels. There was a significant correlation with time delay until the intervention and the risk of urosepsis and PUC, individually. Conclusions: Ureteroscopy is a safe option for evaluation of pregnant patients with unresolved renal colic. According to the current findings, timing of the operation is the most important factor affecting the septic risks and abortion threat. Surgical intervention with URS must be planned as soon as possible

The new Avicenna Roboflex: How does the irrigation system work? Results from an in vitro experiment

Introduction: Since 2012 Elmed has been working on a robot specifically designed for flexible ureteroscopy. After the first version of Avicenna Roboflex, a second version was developed in 2015, with significant changes especially in the irrigation system. We consider mandatory for the endourologist that works with the Avicenna Roboflex be aware of the functioning of the irrigation system. Materials and Methods: We connected a container to the pump’s irrigation system and measured the quantity of saline per second delivered by each speed setting, with/without the flush in five different modalities: pump on its own, pump with ureteroscope, with two laser fibers, with 1.9 Fr basket, and with a Terumo guidewire. Results: The highest mean flow-rates were observed in the 200- micrometer laser fiber, after the pump on its own. Median flowrates for all speed settings were significantly higher for the pump on its own than for the URS in both flushed and nonflushed modes (p = 0.045, p = 0.039 respectively). There was no statistically significant difference in median flow-rates between the guide wire and basket in all of the speed settings (p = 0.932 and p = 0.977). For both laser fibers there was no statistically significant difference between the median flow rate on both nonflush and flush modes. (p = 0.590 & p = 0.590). There was a linear correlation between the speed setting and the increase measured with the flush-option for pump only measurements (r = 0.602, p = 0.038). There was no statistically significant difference between laser fibers and the pump on its own on the increase of flow rate with flush mode. (p = 0.443 for the 272- micrometer fiber and p = 0.219 for the 200-micrometer fiber). Conclusion: The irrigation system of the new Avicenna Roboflex is optimized compared to the previous version. However other more complex studies concerning the live flow/pressure relationship are needed before firm conclusions can be made

Ureteral Access Sheaths and Its Use in the Future: A Comprehensive Update Based on a Literature Review

Ureteral access sheaths (UASs) are part of urologist's armamentarium when performing retrograde intrarenal surgery (RIRS). Recently, the world of RIRS has changed dramatically with the development of three game-changers: thulium fiber laser (TFL), smaller size single use digital flexible ureterosopes and intraoperative intrarenal pressure (IRP) measurement devices. We aimed to clarify the impact of UASs on IRP, complications and SFRs and put its indications in perspective of these three major technological improvements. A systematic review of the literature using the Medline, Scopus and Web of Science databases was performed by two authors and relevant studies were selected according to PRISMA guidelines. Recent studies showed that using a UAS lowers IRP and intrarenal temperature by increasing irrigation outflow during RIRS. Data on the impact of a UAS on SFRs, postoperative pain, risk of infectious complications, risk of ureteral strictures and risk of bladder recurrence of urothelial carcinoma after diagnostic RIRS were inconclusive. Prestenting for at least one week resulted in ureteral enlargement, while the influence of pre-operative administration of alpha-blockers was unclear. Since TFL, smaller single use digital ureteroscopes and devices with integrated pressure-measuring and aspiration technology seemed to increase SFRs and decrease pressure and temperature related complications, indications on the use of a UAS may decrease in the near future

Ureteral access sheaths and its use in the future: A comprehensive update based on a literature review

Ureteral access sheaths (UASs) are part of urologist’s armamentarium when performing retrograde intrarenal surgery (RIRS). Recently, the world of RIRS has changed dramatically with the development of three game-changers: thulium fiber laser (TFL), smaller size single use digital flexible ureterosopes and intraoperative intrarenal pressure (IRP) measurement devices. We aimed to clarify the impact of UASs on IRP, complications and SFRs and put its indications in perspective of these three major technological improvements. A systematic review of the literature using the Medline, Scopus and Web of Science databases was performed by two authors and relevant studies were selected according to PRISMA guidelines. Recent studies showed that using a UAS lowers IRP and intrarenal temperature by increasing irrigation outflow during RIRS. Data on the impact of a UAS on SFRs, postoperative pain, risk of infectious complications, risk of ureteral strictures and risk of bladder recurrence of urothelial carcinoma after diagnostic RIRS were inconclusive. Prestenting for at least one week resulted in ureteral enlargement, while the influence of pre-operative administration of alpha-blockers was unclear. Since TFL, smaller single use digital ureteroscopes and devices with integrated pressure-measuring and aspiration technology seemed to increase SFRs and decrease pressure and temperature related complications, indications on the use of a UAS may decrease in the near future.publishedVersio

New Technologies in Endourology and Laser Lithotripsy: The Need for Evidence in Comprehensive Clinical Settings

Flexible ureteroscopy (fURS) with laser lithotripsy is currently the gold standard surgical treatment for ureteral and kidney stones with a maximum diameter of 2 cm [...]

Simultaneous and synchronous bilateral endoscopic treatment of urolithiasis : a multicentric study

The general prevalence of bilateral urolithiasis has risen to 15% and bilateral non-simultaneous treatment has been reported to have good outcomes. The objective of this study was to evaluate the effectiveness and safety of simultaneous bilateral endoscopic surgery (SBES). An international multicenter analysis was performed between May 2015 and December 2017. All patients with bilateral stone disease that underwent SBES were included. Patients were treated under general anesthesia in either the supine or lithotomy position. Demographic, clinical, intraoperative and postoperative data were analyzed. A total of 47 patients were included. Mean age was 53.8 years and 70% of the patients were males. The mean American Society of Anesthesiology (ASA) score was 2. The mean diameter of right- and left-sided stones was 29.43 mm (2-83 mm) and 31.15 (4-102 mm), respectively. Staghorn stones were treated in 18 cases (8 right-sided and 10 left-sided), four of them were defined as complete staghorn. The procedures performed were 42 cases of bilateral URS and PCNL and ureteroscopy. Additionally, 5 bilateral flexible ureteroscopy (fURS) cases were described. Intraoperative complications occurred in five patients: four of them were classified as Clavien-Dindo (CD) I and one as CD II. Postoperatively, there were two cases with CD I, 6 with CD II and one CD IIIa. The stone-free status was 70%. Residual stones (30%) were detected only on the side treated for high-volume (complete) staghorn calculi. SBES is a feasible, effective and safe procedure. It may potentially avoid repeated anesthetic sessions as needed for staged procedures and reduce the length of patients' hospital stay