Color tunable pressure sensors based on polymer nanostructured membranes for optofluidic applications.

We demonstrate an integrated optical pressure sensing platform for multiplexed optofluidics applications. The sensing platform consists in an array of elastomeric on-side nanostructured membranes -effectively 2D photonic crystal- which present colour shifts in response to mechanical stress that alter their nanostructure characteristical dimensions, pitch or orientation. The photonic membranes are prepared by a simple and cost-effective method based on the infiltration of a 2D colloidal photonic crystal (CPC) with PDMS and their integration with a microfluidic system. We explore the changes in the white light diffraction produced by the nanostructured membranes when varying the pneumatic pressure in the microfluidics channels as a way to achieve a power-free array of pressure sensors that change their reflective colour depending on the bending produced on each sensor. The structural characterization of these membranes was performed by SEM, while the optical properties and the pressure-colour relation were evaluated via UV-Vis reflection spectrometry. Maximum sensitivities of 0.17 kPa-1 is obtained when measuring at Littrow configuration (θin = -θout), and close to the border of the membranes. The reflected colour change with pressure is as well monitorized by using a smartphone camera.

Anestesia subaracnoidea y anestesia general en el tratamiento quirúrgico de la hernia inguinal en pacientes ambulatorios. Análisis comparativo de coste-efectividad / Spinal anesthesia versus general anesthesia in the surgical treatment of inguinal hernia. Cost-effectiveness analysis

Objetivo. Comparar los costes variables en relación con la efectividad clínica de la utilización de anestesia general frente a anestesia subaracnoidea en la cirugía ambulatoria de la hernia inguinal. Material y métodos. Estudio observacional, de cohortes, retrospectivo, con medición y análisis del coste-efectividad, realizado en una unidad de cirugía ambulatoria de un hospital general entre enero de 2010 y diciembre de 2011. Se incluyeron pacientes mayores de 18 años con tratamiento quirúrgico de la hernia inguinal primaria unilateral. Los tiempos de inducción anestésica y permanencia en quirófano y en unidad de recuperación postanestésica, la efectividad anestésica (incidencia de efectos adversos y el grado de bienestar del paciente) y los costes variables asociados al consumo de fármacos y utilización de recursos humanos fueron comparados. Resultados. Se incluyeron 218 pacientes, el 87,2% hombres, con una edad media de 53 años (rango 18 a 85 años). Ciento treinta y nueve (63,76%) pacientes recibieron anestesia subaracnoidea, y 79 (36,2%), anestesia general. La permanencia en recuperación postanestésica fue de 337,6 ± 160,2 min en el grupo de anestesia subaracnoidea y de 210,0 ± 97,5 min para el grupo de anestesia general (p < 0,001). Los costes de los fármacos para anestesia general fueron mayores que para subaracnoidea (86,2 ± 8,3 frente a 18,7 ± 7,2). La diferencia del coste total entre ambas técnicas fue de 115,8 Euros, mayor para el grupo de anestesia subaracnoidea (p < 0,001). Conclusiones. La anestesia subaracnoidea y la general muestran una efectividad similar, pero los costes globales para la primera son mayores que para la segunda. La relación coste-efectividad es más favorable para la anestesia general que para la subaracnoidea en hernioplastia ambulatoria (AU)

Objective. To compare the costs related to the clinical effectiveness of general anesthesia versus spinal anesthesia in inguinal hernioplasty ambulatory surgery. Material and methods. An observational, retrospective cohort study measurement and analysis of cost-effectiveness, in the ambulatory surgery unit of a general hospital. All patients over 18 years of age diagnosed with primary inguinal hernia and scheduled for unilateral hernioplasty between January 2010 and December 2011 were included. Duration of anesthetic induction, length of stay in both the operating room, and in the post-anesthesia care unit, the anesthetic effectiveness (the incidence of adverse effects and the patient's comfort level), and variable economic costs associated with the use of drugs, as well as the use of human resources, were compared. Results. The final analysis included 218 patients, 87.2% male, with a mean age of 53 years (range: 18-85 years). Of these, 139 (63.76%) received subarachnoid anesthesia and 79,(36.2%) general anesthesia. The length of time a patient remained in the post-anesthesia care unit was 337.6 ± 160.2 min in the subarachnoid anesthesia group, and 210.0 ± 97.5 min for the general anesthesia group (P < .001). Costs of drugs for general anesthesia were higher than that for subarachnoid anesthesia (86.2 ± 8.3 vs. 18.7 ± 7.2). The total cost difference between the 2 techniques was Euros 115.8 more for subarachnoid anesthesia (P < .001). Conclusions. Both techniques showed similar effectiveness. The overall costs for subarachnoid anesthesia were greater than for the general. The cost-effectiveness of general anesthesia is better for outpatient inguinal hernia repair surgery (AU)

[Spinal anesthesia versus general anesthesia in the surgical treatment of inguinal hernia. Cost-effectiveness analysis]. / Anestesia subaracnoidea y anestesia general en el tratamiento quirúrgico de la hernia inguinal en pacientes ambulatorios. Análisis comparativo de coste-efectividad.

OBJECTIVE: To compare the costs related to the clinical effectiveness of general anesthesia versus spinal anesthesia in inguinal hernioplasty ambulatory surgery. MATERIAL AND METHODS: An observational, retrospective cohort study measurement and analysis of cost-effectiveness, in the ambulatory surgery unit of a general hospital. All patients over 18 years of age diagnosed with primary inguinal hernia and scheduled for unilateral hernioplasty between January 2010 and December 2011 were included. Duration of anesthetic induction, length of stay in both the operating room, and in the post-anesthesia care unit, the anesthetic effectiveness (the incidence of adverse effects and the patient's comfort level), and variable economic costs associated with the use of drugs, as well as the use of human resources, were compared. RESULTS: The final analysis included 218 patients, 87.2% male, with a mean age of 53 years (range: 18-85 years). Of these, 139 (63.76%) received subarachnoid anesthesia and 79,(36.2%) general anesthesia. The length of time a patient remained in the post-anesthesia care unit was 337.6±160.2min in the subarachnoid anesthesia group, and 210.0±97.5min for the general anesthesia group (P<.001). Costs of drugs for general anesthesia were higher than that for subarachnoid anesthesia (86.2±8.3 vs. 18.7±7.2). The total cost difference between the 2 techniques was €115.8 more for subarachnoid anesthesia (P<.001). CONCLUSIONS: Both techniques showed similar effectiveness. The overall costs for subarachnoid anesthesia were greater than for the general. The cost-effectiveness of general anesthesia is better for outpatient inguinal hernia repair surgery.

Intra-abdominal pulmonary secuestration as an exceptional cause of abdominal mass in the adult.

INTRODUCTION: Pulmonary sequestration (PS) is an extremely rare malformation defined as a portion of lung tissue isolated from the pulmonary system. PSs are classified into intralobar type and intra-abdominal PS that represents only 2.5% of cases. There are 20 cases of PS reported in adults and only two were managed by laparoscopic approach. We report a case of intra-abdominal PS mimicking a gastroesophageal duplication cyst in an adult. Besides its rarity, this is the first intra-abdominal PS in an adult managed by an anterior laparoscopic approach. PRESENTATION OF CASE: A 60-year-old female patient had had epigastric and left upper quadrant pain for several days. Physical examination was normal. Image test were consistent with a gastroesophageal duplication. The patient was taken to the operating room for laparoscopic exploration and resection. The pathological diagnosis was extralobar pulmonary sequestration. DISCUSSION: Less than 20 cases of PS have been reported in adults and only two cases were managed by a lateral laparoscopic approach. In contrast to these reports, we used an anterior approach due to the GEJ suspected origin of the mass. CONCLUSION: Extralobar intra-abdominal PS is an extremely rare condition during adulthood but this diagnosis should be included in the differential diagnosis of a left-sided suprarenal mass. Due to the difficulty in achieving a definitive preoperative diagnosis, surgery is recommended. Laparoscopic resection is safe and effective but careful preoperative imaging studies are recommended in order to plan the most suitable approach.

Flexible probe for in vivo quantification of corneal epithelium permeability through non-invasive tetrapolar impedance measurements.

Studies concerning the functional status of the corneal epithelium are of special interest due to its key role in preventing ocular surface disease and corneal infections. In particular, quantitative measurements of the epithelium permeability translayer electrical resistance (TER) have been proven as a sensitive in vitro test for evaluation of the corneal barrier function. In a recent work from the authors (Guimera et al. Biosens. Bioelectron. 31:55-61, 2012), a novel method to non-invasively assess the corneal epithelial permeability by using tetrapolar impedance measurements, based on the same TER theoretical principles, was presented and validated using a rigid sensing device. In this work, the usability of this method has been dramatically improved by using SU-8 photoresist as a substrate material. The flexibility of this novel sensing device makes no need to apply pressure on the cornea to ensure the electrical contact between the electrodes and the corneal surface. The feasibility of this flexible sensor has been evaluated in vivo by increasing the permeability of rabbit corneal epithelium. For that, different concentrations of benzalkonium chloride (BAC) solution were instilled on different rabbit corneas. The obtained results have been compared with measurements of the permeability to sodium fluorescein of different excised corneas, a well-known method used to evaluate the corneal barrier function, to demonstrate the feasibility of this novel flexible sensor for quantifying the corneal epithelium permeability in vivo in a non-invasive way.

Pelvic reconstruction after abdominoperineal resection: a pilot study using an absorbable synthetic prosthesis.

BACKGROUND: Abdominoperineal resection (APR) is not free of complications, in particular complications due to the occupation of the pelvis by the small bowel after surgery. A number of surgical techniques have been described to prevent the small bowel from entering and adhering to the pelvis (pelvic partition), but there is no agreement concerning their use. The aim of this study was to evaluate the feasibility, effectiveness and safety of using an absorbable synthetic prosthetic material for pelvic partitioning after APR. METHODS: A prospective non-randomised longitudinal pilot study was carried out on a series of 10 patients who underwent APR due to lower-third rectal cancer, in order to evaluate the feasibility, safety and efficacy of pelvic partitioning with an absorbable synthetic prosthetic material. RESULTS: In all the patients, it was possible to perform a radical resection and to install the prosthesis. After a mean follow-up of 9 months (range: 4-18 months), no abdominal or perineal complications were detected. One patient (10%) suffered chronic pelvic pain. CONCLUSIONS: Pelvic partition after APR of the rectum with an absorbable synthetic prosthesis is feasible, effective and safe.