Albuterol delivery in an in vitro pediatric ventilator lung model: comparison of jet, ultrasonic, and mesh nebulizers.

OBJECTIVE: : To determine the influence of nebulizer types and nebulization modes on bronchodilator delivery in a mechanically ventilated pediatric lung model. DESIGN: : In vitro, laboratory study. SETTING: : Research laboratory of a university hospital. INTERVENTIONS: : Using albuterol as a marker, three nebulizer types (jet nebulizer, ultrasonic nebulizer, and vibrating-mesh nebulizer) were tested in three nebulization modes in a nonhumidified bench model mimicking the ventilatory pattern of a 10-kg infant. The amounts of albuterol deposited on the inspiratory filters (inhaled drug) at the end of the endotracheal tube, on the expiratory filters, and remaining in the nebulizers or in the ventilator circuit were determined. Particle size distribution of the nebulizers was also measured. MEASUREMENTS AND MAIN RESULTS: : The inhaled drug was 2.8% ± 0.5% for the jet nebulizer, 10.5% ± 2.3% for the ultrasonic nebulizer, and 5.4% ± 2.7% for the vibrating-mesh nebulizer in intermittent nebulization during the inspiratory phase (p < 0.01). The most efficient nebulizer was the vibrating-mesh nebulizer in continuous nebulization (13.3% ± 4.6%, p < 0.01). Depending on the nebulizers, a variable but important part of albuterol was observed as remaining in the nebulizers (jet and ultrasonic nebulizers), or being expired or lost in the ventilator circuit (all nebulizers). Only small particles (range 2.39-2.70 µm) reached the end of the endotracheal tube. CONCLUSIONS: : Important differences between nebulizer types and nebulization modes were seen for albuterol deposition at the end of the endotracheal tube in an in vitro pediatric ventilator-lung model. New aerosol devices, such as ultrasonic and vibrating-mesh nebulizers, were more efficient than the jet nebulizer.

Fibrin sealant for mesh fixation in endoscopic inguinal hernia repair: is there enough evidence for its routine use?

Fibrin sealing has recently evolved as a new technique for mesh fixation in endoscopic inguinal hernia repair. A comprehensive Medline search was carried out evaluating fibrin sealant for mesh fixation, and finally 12 studies were included (3 randomized trials, 3 nonrandomized trials, and 6 case series). The trials were assessed for operative time, seroma formation, recovery time, recurrence rate, and acute and chronic pain.There was a trend toward decreased operative times for fibrin sealing compared with mechanical stapling; however, the results for seroma formation remained contradictory. The most important finding was the reduced postoperative pain. Recovery times were lower after fibrin sealing and the recurrence rates showed no differences.Fibrin sealing for mesh fixation in the endoscopic inguinal hernia surgery is a promising alternative to mechanical stapling, which can be safely applied. As the overall quality of published data remains poor, further well-designed studies are needed until fibrin sealing can replace mechanical stapling as a new standard for mesh fixation.

Surgery for incarcerated hernia: short-term outcome with or without mesh.

BACKGROUND: Incarcerated hernias represent about 5-15 % of all operated hernias. Tension-free mesh is the preferred technique for elective surgery due to low recurrence rates. There is however currently no consensus on the use of mesh for the treatment of incarcerated hernias, especially in case of bowel resection. AIM: The aims of this study were (i) to report our current practice for the treatment of incarcerated hernias, (ii) to identify risk factors for postoperative complications, and (iii) to assess the safety of mesh placement in potentially infected surgical fields. METHODS: This retrospective study included 166 consecutive patients who underwent emergency surgery for incarcerated hernia between January 2007 and January 2012 in two university hospitals. Demographics, surgical details, and short-term outcome were collected. Univariate analysis was employed to identify risk factors for overall, infectious, and major complications. RESULTS: Eighty-four patients (50.6 %) presented inguinal hernias, 43 femoral (25.9 %), 37 umbilical hernias (22.3 %), and 2 mixed hernias (1.2 %), respectively. Mesh was placed in 64 patients (38.5 %), including 5 patients with concomitant bowel resection. Overall morbidity occurred in 56 patients (32.7 %), and 8 patients (4.8 %) developed surgical site infections (SSI). Univariate risk factors for overall complications were ASA grade 3/4 (P = 0.03), diabetes (P = 0.05), cardiopathy (P = 0.001), aspirin use (P = 0.023), and bowel resection (P = 0.001) which was also the only identified risk factor for SSI (P = 0.03). In multivariate analysis, only bowel incarceration was associated with a higher rate of major morbidity (OR = 14.04; P = 0.01). CONCLUSION: Morbidity after surgery for incarcerated hernia remains high and depends on comorbidities and surgical presentation. The use of mesh could become current practice even in case of bowel resection.

Short- and long-term effects of litter size manipulation in a small wild-derived rodent.

Iteroparous organisms maximize their overall fitness by optimizing their reproductive effort over multiple reproductive events. Hence, changes in reproductive effort are expected to have both short- and long-term consequences on parents and their offspring. In laboratory rodents, manipulation of reproductive efforts during lactation has however revealed few short-term reproductive adjustments, suggesting that female laboratory rodents express maximal rather than optimal levels of reproductive investment as observed in semelparous organisms. Using a litter size manipulation (LSM) experiment in a small wild-derived rodent (the common vole; Microtus arvalis), we show that females altered their reproductive efforts in response to LSM, with females having higher metabolic rates and showing alternative body mass dynamics when rearing an enlarged rather than reduced litter. Those differences in female reproductive effort were nonetheless insufficient to fully match their pups' energy demand, pups being lighter at weaning in enlarged litters. Interestingly, female reproductive effort changes had long-term consequences, with females that had previously reared an enlarged litter being lighter at the birth of their subsequent litter and producing lower quality pups. We discuss the significance of using wild-derived animals in studies of reproductive effort optimization.

Adverse effects of intraperitoneal onlay mesh used for incisional hernia repair

Context: In the past 50 years, the use of prosthetic mesh in surgery has dramatically¦changed the management of primary, as well as incisional hernias. Currently, there¦are a large number of different mesh brands and no consensus on the best material,¦nor the best mesh implantation technique to use. The purpose of this study is to¦illustrate the adverse effects of intraperitoneal onlay mesh used for incisional¦hernia repair encountered in patients treated at CHUV for complications after¦incisional hernia repair.¦Materials & Methods: This work is an observational retrospective study. A PubMed¦search and a systematic review of literature were performed. Thereafter, the medical¦records of 22 patients who presented with pain, abdominal discomfort, ileus, fistula,¦abscess, seroma, mesh infection or recurrent incisional hernia after a laparoscopic or¦open repair with intra-abdominal mesh were reviewed.¦Results: Twenty-two persons were reoperated for complications after incisional¦hernia repair with a prosthetic mesh. Ten were male and twelve female, with a¦median age of 58,6 years (range 24-82). Mesh placement was performed by a¦laparoscopic approach in nine patients and by open approach in thirteen others.¦Eight different mesh brands were found (Ultrapro®, Mersilene®, Parietex Composite®,¦Proceed®, DynaMesh®, Gore® DualMesh®, Permacol®, Titanium Metals UK Ltd®).¦Mean time from implantation and reoperation for complication was 34.2 months¦(range 1-147). In our sample of 22 patients, 21 (96%) presented mesh adhesion and¦15 (68%) presented hernia recurrence. Others complications like mesh shrinkage,¦mesh migration, nerve entrapment, seroma, fistula and abscess were also evaluated.¦Conclusion: The majority of articles deal with complications induced by¦intraperitoneal prosthetic mesh, but the effectiveness of mesh has been studied¦mostly on experimental models. Actually and as shown in the present study,¦intraperitoneal mesh placement was associated with severe complications witch may¦potentially be life threatening. In our opinion, intraperitoneal mesh placement should¦only be reserved in exceptional situations, when the modified Rives-Stoppa could not¦be achieved and when tissues covering the mesh are insufficient.

Laparoscopic inguinal hernia repair with extraperitoneal double-mesh technique.

Totally extraperitoneal laparoscopic hernia repair is an efficient but technically demanding procedure. As mechanisms of hernia recurrence may be related to these technical difficulties, we have modified a previously described double-mesh technique in an effort to simplify the procedure. Extraperitoneal laparoscopic hernia repairs were performed in 82 male and 17 female patients having inguinal, femoral, and recurrent bilateral hernias. A standard propylene mesh measuring 15 x 15 cm was cut into two pieces of 4 x 15 cm and 11 x 15 cm. The smaller mesh was placed over both inguinal rings without splitting. The larger mesh was then inserted over the first mesh and stapled to low-risk zones, reinforcing the large-vessel area and the nerve transition zone. The mean procedure duration was 60 minutes for unilateral and 100 minutes for bilateral hernia repair. Patients were discharged from the hospital within 48 hours. The mean postoperative follow-up was 22 months, with no recurrences, neuralgia, or bleeding complications. Over a 2-year period, this technique was found to be satisfactory without recurrences or significant complications. In our hands, this technique was easier to perform: it allows for a less than perfect positioning of the meshes and avoids most of the stapling to crucial zones.

Accuracy and predictability in use of AO three-dimensionally preformed titanium mesh plates for posttraumatic orbital reconstruction: a pilot study.

The aim of this study was to prospectively evaluate the accuracy and predictability of new three-dimensionally preformed AO titanium mesh plates for posttraumatic orbital wall reconstruction.We analyzed the preoperative and postoperative clinical and radiologic data of 10 patients with isolated blow-out orbital fractures. Fracture locations were as follows: floor (N = 7; 70%), medial wall (N = 1; 1%), and floor/medial wall (N = 2; 2%). The floor fractures were exposed by a standard transconjunctival approach, whereas a combined transcaruncular transconjunctival approach was used in patients with medial wall fractures. A three-dimensional preformed AO titanium mesh plate (0.4 mm in thickness) was selected according to the size of the defect previously measured on the preoperative computed tomographic (CT) scan examination and fixed at the inferior orbital rim with 1 or 2 screws. The accuracy of plate positioning of the reconstructed orbit was assessed on the postoperative CT scan. Coronal CT scan slices were used to measure bony orbital volume using OsiriX Medical Image software. Reconstructed versus uninjured orbital volume were statistically correlated.Nine patients (90%) had a successful treatment outcome without complications. One patient (10%) developed a mechanical limitation of upward gaze with a resulting handicapping diplopia requiring hardware removal. Postoperative orbital CT scan showed an anatomic three-dimensional placement of the orbital mesh plates in all of the patients. Volume data of the reconstructed orbit fitted that of the contralateral uninjured orbit with accuracy to within 2.5 cm(3). There was no significant difference in volume between the reconstructed and uninjured orbits.This preliminary study has demonstrated that three-dimensionally preformed AO titanium mesh plates for posttraumatic orbital wall reconstruction results in (1) a high rate of success with an acceptable rate of major clinical complications (10%) and (2) an anatomic restoration of the bony orbital contour and volume that closely approximates that of the contralateral uninjured orbit.

Computer-aided volume measurement of posttraumatic orbits reconstructed with AO titanium mesh plates: accuracy and reliability

PURPOSE: To prospectively evaluate the accuracy and reliability of "freehand" posttraumatic orbital wall reconstruction with AO (Arbeitsgemeinschaft Osteosynthese) titanium mesh plates by using computer-aided volumetric measurement of the bony orbits. METHODS: Bony orbital volume was measured in 12 patients from coronal CT scan slices using OsiriX Medical Image software. After defining the volumetric limits of the orbit, the segmentation of the bony orbital region of interest of each single slice was performed. At the end of the segmentation process, all regions of interest were grouped and the volume was computed. The same procedure was performed on both orbits, and thereafter the volume of the contralateral uninjured orbit was used as a control for comparison. RESULTS: In all patients, the volume data of the reconstructed orbit fitted that of the contralateral uninjured orbit with accuracy to within 1.85 cm3 (7%). CONCLUSIONS: This preliminary study has demonstrated that posttraumatic orbital wall reconstruction using "freehand" bending and placement of AO titanium mesh plates results in a high success rate in re-establishing preoperative bony volume, which closely approximates that of the contralateral uninjured orbit.

Comparison of three separate antiadhesive barriers for intraperitoneal onlay mesh hernia repair in an experimental model (Br J Surg 2011; 98: 442-449).

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The use of external mesh reinforcement to reduce intimal hyperplasia and preserve the structure of human saphenous veins.

The saphenous vein is the conduit of choice in bypass graft procedures. Haemodynamic factors play a major role in the development of intimal hyperplasia (IH), and subsequent bypass failure. To evaluate the potential protective effect of external reinforcement on such a failure, we developed an ex vivo model for the perfusion of segments of human saphenous veins under arterial shear stress. In veins submitted to pulsatile high pressure (mean pressure at 100 mmHg) for 3 or 7 days, the use of an external macroporous polyester mesh 1) prevented the dilatation of the vessel, 2) decreased the development of IH, 3) reduced the apoptosis of smooth muscle cells, and the subsequent fibrosis of the media layer, 4) prevented the remodelling of extracellular matrix through the up-regulation of matrix metalloproteinases (MMP-2, MMP-9) and plasminogen activator type I. The data show that, in an experimental ex vivo setting, an external scaffold decreases IH and maintains the integrity of veins exposed to arterial pressure, via increase in shear stress and decrease wall tension, that likely contribute to trigger selective molecular and cellular changes.

Ecologie d'une population de Crocidura russula en milieu rural montagnard (Insectivora, Soricidae)

Crocidura russula is restricted to the vicinity of human dwellings in the northern parts of its range and in the mountain regions of Central and Western Europe. In order to better understand the causes of such a distribution, a population was studied in a rural mountain habitat (750 m above sea level), where the species was found almost exclusively in the neighbourhood of human dwellings. The study was conducted on a 2000 m2 area, over a period of 20 months, by live-trapping and radioactive tracking. The abundance, the local distribution and the behaviour of the shrews vary greatly throughout the year. In summer, they chiefly inhabit areas with a dense herbaceous cover or shruby vegetation; they are mainly active at ground level, in the litter. In autumn, changes in the environmental conditions (lowering of temperatures, subsidence of the herbaceous vegetation, presence of snow) create important energetic problems. At that time, the shrews gradually become more active around and inside compost-heaps and buildings. The microclimate of such environments is mild and prey are numerous. The winter population is reduced (reaching its lowest level in late winter) and consists only of shrews frequenting these sites. The observed spatial distribution is the result of the energetic dependence of the wintering shrews on human dwellings and their surroundings. This dependence is probably related to the physiological characteristics of the species. In the prospected region, Crocidura russula is the only shrew which regularly takes advantage of man-made habitats; the maintenance of the species in the rural mountain enviroment is probably favoured by the social organization of the populations in winter. The other native Soricids are observed only occasionaly int he neighbourhood of human dwellings.

Die Inguinal-Hernienplastik nach Lichtenstein: Eine einfache und komplikationsarme Technik, besonders geeignet für die Tageschirurgie [The Lichtenstein inguinal hernia-plasty: a simple and complication-free technique, especially suited for ambulatory surgery].

A consecutive series of 353 patients who underwent Lichtenstein mesh repair for inguinal hernia from the 1st of July 1994 to the 30th of July 1995 were studied. We analysed our indication, technique, complications, follow-up and outcome. Special consideration was given to the advantages and acceptance of day-case surgery. Our results suggest that the Lichtenstein repair should be considered as a new standard procedure, especially outside of hernia centres.

Swiss survey on salt intake: main results

[Contents] 1. Executive summary. 2. Introduction. 3. Methods. 4. Main results. 4.1. Participants. 4.2. Estimation of dietary salt intake using 24-hour urine collection. 4.3. Blood pressure and hypertension. 4.4. Anthropometric data (Body weight, height and body mass index BMI; prevalence of overweight and obesity; waist circumference;...). 4.5. Knowledge and behaviors towards salt. 5. Discussion.