42 research outputs found
Early detection of subglottic bridge-stenosis following long-term transoral intubation and tracheotomy
Subglottic bridge stenosis (SgBS) after long-term intubation, followed by tracheostomy, which separates the subglottic lumen into an anterior and posterior channels presents a rarity. If not diagnosed it could lead to impairment of the breathing and can be mistaken for bilateral vocal fold paralysis.MATERIAL AND METHODS: A prospective study of the value of transstomal endoscopy with angulated endoscopes to detect subglottic lesions in patients, subjected to tracheostomy after being intubated through the larynx as a routine examination before decannulation. Rigid angulated endoscopes of the Hopkins type with 70o and 90o degrees were used for retrograde transstomal laryngoscopy.RESULTS: Examined were 23 consecutive patients (17 male, 6 female, aged 55,4 ±14 years), which had initially transoral intubation for assisted mechanical ventilation, which later was changed to tracheostomy. In 19/23 (82,6%) of the patients the endoscopic examinations revealed no pathology. In 3/23 (13,4%) transoral laryngoscopy showed immobile vocal folds. The supplementary retrograde transstomal laryngoscopy allowed to differentiate between SgBS (two cases; 8,7%) and vocal fold paralysis (one case; 4,3%). The two cases with SgBS were success fully treated using an endoscopic microlaryngeal technique.CONCLUSION: SgBS are hard to be noticed with standard transoral/transnasal laryngeal endoscopy. The clinical constellation of long-term transoral intubation, followed by tracheostomy seems to be predisposing for the formation of SgBS. The retrograde transstomal laryngocopy is a low resource consuming method, which can be used even in un conscious patients, which do not cooperate for the examination. It allows for optimal examination of the subglottis, the stoma and the trachea before decannulation
CLINICAL OUTCOME OF INTERSPHINCTERIC RESECTION FOR ULTRA-LOW RECTAL CANCER
BACKGROUND: Laparoscopic surgery has been reported to be one of the approaches for total mesorectal excision (TME) in rectal cancer surgery. Intersphincteric resection (ISR) has been reported as a promising method for sphincter-preserving operation in selected patients with very low rectal cancer. METHODS: We try to underline the important surgical issues surrounding the management of patients with low rectal cancer indicated to laparoscopic intersphincteric resection (ISR). From January 2007 till now, 35 patients with very low rectal cancer underwent laparoscopic TME with ISR. We report and analyze the results from them RESULTS: Conversion to open surgery was necessary in one (3%) patient. The median operation time was 293 min and median estimated blood loss was 40 ml. The pelvic plexus was completely preserved in 32 patients. There was no mortality. Postoperative complications occurred in three (9%) patients. The median length of postoperative hospital stay was 11 days. Macroscopic complete mesorectal excision was achieved in all cases. Complete resection (R0) was achieved in 21 (91%) patients.CONCLUSIONS: Laparoscopic TME with ISR is technically feasible and a safe alternative to laparotomy with favorable short-term postoperative outcomes. The literature research made by us found that the laparoscopic approach can be underwent in most patients with low rectal cancer in which laparoscopic ISR represents a feasible alternative to conventional open surgery
Buoyancy-driven motion of a deformable drop toward a planar wall at low Reynolds number
Hysteresis of the Contact Angle of a Meniscus Inside a Capillary with Smooth, Homogeneous Solid Walls
This paper was accepted for publication in the journal Langmuir: the ACS journal of surfaces and colloids and the definitive published version is available at http://dx.doi.org/10.1021/acs.langmuir.6b00721.A theory of contact angle hysteresis of a
meniscus inside thin capillaries with smooth, homogeneous solid walls is developed in terms of surface forces (disjoining/
conjoining pressure isotherm) using a quasi-equilibrium approach. The disjoining
/conjoining pressure isotherm includes electrostatic, intermolecular, and structural components. The values of the static receding θr, advancing θa , and
equilibrium θe contact angles in thin capillaries were calculated on the basis of the shape of the disjoining/conjoining pressure isotherm. It was shown that both advancing and receding contact angles depend on the capillary radius. The suggested
mechanism of the contact angle hysteresis has a direct experimental confirmation: the process of receding is accompanied by the formation of thick β-films on the capillary walls. The effect of the transition from partial to complete wetting in thin capillaries is predicted and analyzed. This effect takes place in very thin capillaries, when the receding contact angle decreases to zero
Hysteresis of Contact Angle of Sessile Droplets on Smooth Homogeneous Solid Substrates via Disjoining/Conjoining Pressure
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Langmuir copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.langmuir.5b01075A theory of contact angle hysteresis of liquid droplets on smooth, homogeneous solid substrates is developed in terms of the shape of the disjoining/conjoining pressure isotherm and quasi-equilibrium phenomena. It is shown that all contact angles, θ, in the range θr < θ < θa, which are different from the unique equilibrium contact angle θ ≠ θe, correspond to the state of slow “microscopic” advancing or receding motion of the liquid if θe < θ < θa or θr < θ < θe, respectively. This “microscopic” motion almost abruptly becomes fast “macroscopic” advancing or receding motion after the contact angle reaches the critical values θa or θr, correspondingly. The values of the static receding, θr, and static advancing, θa, contact angles in cylindrical capillaries were calculated earlier, based on the shape of disjoining/conjoining pressure isotherm. It is shown now that (i) both advancing and receding contact angles of a droplet on a on smooth, homogeneous solid substrate can be calculated based on shape of disjoining/conjoining pressure isotherm, and (ii) both advancing and receding contact angles depend on the drop volume and are not unique characteristics of the liquid–solid system. The latter is different from advancing/receding contact angles in thin capillaries. It is shown also that the receding contact angle is much closer to the equilibrium contact angle than the advancing contact angle. The latter conclusion is unexpected and is in a contradiction with the commonly accepted view that the advancing contact angle can be taken as the first approximation for the equilibrium contact angle. The dependency of hysteresis contact angles on the drop volume has a direct experimental confirmation
Methods of measuring rheological properties of interfacial layers (Experimental methods of 2D rheology)
Chronicles of Foam Films
The history of the scientific research on foam films, traditionally known as soap films, dates back to as early as the late 17th century when Boyle and Hooke paid special attention to the colours of soap bubbles. Their inspiration was transferred to Newton, who began systematic study of the science of foam films. Over the next centuries, a number of scientists dealt with the open questions of the drainage, stability and thickness of foam films. The significant contributions of Plateau and Gibbs in the middle/late 19th century are particularly recognized. After the “colours” method of Newton, Reinold and Rücker as well as Johhonnot developed optical methods for measuring the thickness of the thinner “non-colour” films (first order black) that are still in use today. At the beginning of the 20th century, various aspects of the foam film science were elucidated by the works of Dewar and Perrin and later by Mysels. Undoubtedly, the introduction of the disjoining pressure by Derjaguin and the manifestation of the DLVO theory in describing the film stability are considered as milestones in the theoretical development of foam films. The study of foam films gained momentum with the introduction of the microscopic foam film methodology by Scheludko and Exerowa, which is widely used today. This historical perspective serves as a guide through the chronological development of knowledge on foam films achieved over several centuries
Early detection of subglottic bridge-stenosis following long term transoral intubation and tracheotomy
Subglottische Brückensynechien (SgBS) nach Langzeitintubation und Tracheotomie, die sowohl dorsal als auch ventral ein Lumen freilassen, sind Raritäten. Nicht diagnostiziert führen sie zur Beeinträchtigung der Atmung und werden häufig mit einer Stimmlippenlähmung verwechselt. Material und Methode: Prospektive Untersuchung der Wertigkeit einer routinenmäßigen transstomatalen Laryngoskopie (TSLS) vor Dekanülierung an 23 konsekutiven tracheotomierten Patienten. Ergebnisse: Bei insgesamt 23 Erwachsenen (17 m, 6 w, 55,4±14 J) wurde im Rahmen einer Langzeitbeatmung ein Tracheostoma angelegt. Bei 2/23 (8,7%) traten SgBS auf. Bei einem Patienten zeigte sich nach der zunächst erfolgreichen Dekanülierung und Tracheostomaverschluss eine zunehmende Luftnot mit Stridor und eine beiderseitige Stimmbandunbeweglichkeit. Darauf erfolgte eine Retracheotomie. Die TSLS zeigte eine etwa 3 mm im Durchmesser große und etwa 8 mm unter der freien Stimmbandkante gelegene SgBS. Sie wurde transoral in ITN durchgetrennt und ein Swissroll Silikonplatzhalter über 3 Tage eingelegt. Seit dem wurde bei allen Patienten vor der Dekanülierung eine TSLS als Standartuntersuchung durchgeführt. Bei dieser nun routinmäßigen Nachuntersuchung wurde auch ein zweiter Patient mit einer SgBS diagnostiziert. Schlussfolgerung: SgBS sind bei der standartmäßigen transoralen Lupenlaryngoskopie schwer von Stimmlippenlähmungen zu unterscheiden. Eine klinische Konstellation von transoraler Langzeitintubation gefolgt von Tracheotomie erscheint für die entstehung von SgBS prädisponierend. Die TSLS ist eine zeitunaufwendige Methode, die auch bei kooperationsunfähigen Patienten durchführbar ist und ermöglicht eine optimale Beurteilung des Kehlkopfs, der Trachea und des Stomas vor Dekanülierung