New CFD tools to evaluate nasal airflow.

Computational fluid dynamics (CFD) is a mathematical tool to analyse airflow. As currently CFD is not a usual tool for rhinologists, a group of engineers in collaboration with experts in Rhinology have developed a very intuitive CFD software. The program MECOMLAND® only required snapshots from the patient's cross-sectional (tomographic) images, being the output those results originated by CFD, such as airflow distributions, velocity profiles, pressure, temperature, or wall shear stress. This is useful complementary information to cover diagnosis, prognosis, or follow-up of nasal pathologies based on quantitative magnitudes linked to airflow. In addition, the user-friendly environment NOSELAND® helps the medical assessment significantly in the post-processing phase with dynamic reports using a 3D endoscopic view. Specialists in Rhinology have been asked for a more intuitive, simple, powerful CFD software to offer more quality and precision in their work to evaluate the nasal airflow. We present MECOMLAND® and NOSELAND® which have all the expected characteristics to fulfil this demand and offer a proper assessment with the maximum of quality plus safety for the patient. These programs represent a non-invasive, low-cost (as the CT scan is already performed in every patient) alternative for the functional study of the difficult rhinologic case. To validate the software, we studied two groups of patients from the Ear Nose Throat clinic, a first group with normal noses and a second group presenting septal deviations. Wall shear stresses are lower in the cases of normal noses in comparison with those for septal deviation. Besides, velocity field distributions, pressure drop between nasopharynx and the ambient, and flow rates in each nostril were different among the nasal cavities in the two groups. These software modules open up a promising future to simulate the nasal airflow behaviour in virtual surgery intervention scenarios under different pressure or temperature conditions to understand the effects on nasal airflow.

Arthroscopic fibroarthrolysis and mobilization under anesthesia is a simple, reproducible, and satisfactory method for the treatment of patients with severe post-traumatic arthrofibrosis of the knee.

OBJECTIVE: To evaluate the range of motion (ROM) of the knee in patients with severe post-traumatic knee arthrofibrosis after being treated with arthroscopic fibroarthrolysis (AFA) and manipulation under anesthesia (MUA). METHODS: Case series of patients with severe post-traumatic knee arthrofibrosis who underwent AFL+MUA in a national referral center. The primary outcome to be assessed was ROM before and after surgery and then at 3-month intervals until a minimum follow-up of one year was completed. RESULTS: 51 patients were included. The main injuries preceding the stiffness were tibial plateau fracture (37.3%), distal femur fracture (27.5%), and femoral shaft fracture (15.7%). Forty-five patients had severe flexion deficits with a median preoperative flexion of 70°. Intraoperative flexion significantly improved to 110°. Significant loss of flexion was observed at 3 and 6 months, however, patients regained ROM in the 9 and 12-month follow-ups. At discharge, 80% of the patients achieved flexion of 90° or more. There were 4 intraoperative complications and 3 reinterventions were performed. CONCLUSION: AFA+MUA can help patients with severe post-traumatic knee arthrofibrosis to recover ROM in most cases. However, this procedure is not without risks and complications, therefore, careful consideration should be given to its indication and execution.

The use of arthroscopy does not increase the incidence of complications in the management of Schatzker IV-VI tibial plateau fractures. / El uso de artroscopia no aumenta la incidencia de complicaciones en el manejo de fracturas de mesetas tibiales Schatzker IV-VI.

BACKGROUND AND OBJECTIVE: The use of arthroscopy for tibial plateau fractures type I, II and III according to Schatzker classification has increased, yet its employment for tibial plateau fractures Schatzker IV, V and VI is controversial due to the potential risk of compartment syndrome, deep vein thrombosis and infection. We aimed to compare the rate of operative and postoperative complications among patients with these types of tibial plateau fractures treated with and without arthroscopy at the time of definitive reduction and osteosynthesis. METHODS: Retrospective cohort study. Patients with diagnosis of tibial plateau fracture Schatzker IV, V or VI who underwent reduction and definitive osteosynthesis with or without the use of arthroscopy were included. The development of compartment syndrome, deep vein thrombosis, and fracture-related infection was evaluated up to 12 months after the definitive surgery. RESULTS: Two hundred eighty-eight patients were included: 86 with arthroscopic assistance and 202 without it. The overall complication rate in the group with and without arthroscopic assistance was 18.60% and 26.73%, respectively (P=.141). No statistical association was found between the use of arthroscopic assistance and the development of the analyzed complications. DISCUSSION AND CONCLUSION: The use of arthroscopy to support reduction or addressing concomitant intra-articular injuries did not increase the risk of complications in patients with high-energy tibial plateau fractures at 12 months of follow up.

[Translated article] The use of arthroscopy does not increase the incidence of complications in the management of Schatzker IV-VI tibial plateau fractures.

BACKGROUND AND OBJECTIVE: The use of arthroscopy for tibial plateau fractures type I, II and III according to Schatzker classification has increased, yet its employment for tibial plateau fractures Schatzker IV, V and VI is controversial due to the potential risk of compartment syndrome, deep vein thrombosis and infection. We aimed to compare the rate of operative and postoperative complications among patients with these types of tibial plateau fractures treated with and without arthroscopy at the time of definitive reduction and osteosynthesis. METHODS: Retrospective cohort study. Patients with diagnosis of tibial plateau fracture Schatzker IV, V or VI who underwent reduction and definitive osteosynthesis with or without the use of arthroscopy were included. The development of compartment syndrome, deep vein thrombosis, and fracture-related infection was evaluated up to 12 months after the definitive surgery. RESULTS: Two hundred eighty-eight patients were included: 86 with arthroscopic assistance and 202 without it. The overall complication rate in the group with and without arthroscopic assistance was 18.60% and 26.73%, respectively (p=.141). No statistical association was found between the use of arthroscopic assistance and the development of the analysed complications. DISCUSSION AND CONCLUSION: The use of arthroscopy to support reduction or addressing concomitant intra-articular injuries did not increase the risk of complications in patients with high-energy tibial plateau fractures at 12 months of follow up.

Progressive perioperative benefits of laparoscopy in combination with an ERAS (Enhanced Recovery After Surgery) protocol in radical cystectomy with ileal conduit. / Beneficios perioperatorios progresivos de la laparoscopia y su combinación con un programa Enhanced recovery after surgery (ERAS) en la cistectomía radical con derivación urinaria heterotópica.

INTRODUCTION: Although in the recent years, laparoscopy and Enhanced Recovery After Surgery (ERAS) protocols have improved postoperative recovery in radical cystectomy (RC), the clinical efficacy of their association remains unclear. Our objective is to analyze the possible benefits obtained from laparoscopic RC (LRC) and its subsequent combination with an ERAS (ERAS-LRC) protocol compared to open RC (ORC). MATERIAL AND METHODS: We analyzed 187 consecutive RCs with ileal conduit performed in our center, of which 139 met the inclusion criteria: 47 ORC, 39 LRC (both with conventional protocol) and 52 ERAS-LRCs. RESULTS: No significant differences were found regarding age, sex, BMI and ASA score between groups. ERAS-LRC obtained a shorter length of stay than LRC and ORC (median 8 [7-10]) vs. 13 [10-17] vs. 15 [13-19.5] days, respectively; P<.001). ERAS-LRC had a shorter stay in the ICU and less days of nasogastric tube (P<.001). Postoperative complications and readmission rates were similar among groups. Multivariate logistic regression showed that absence of complications, younger age and ERAS behaved as independent factors for shorter hospital stay, while ERAS was the only independent factor of lower readmission rate at 90 days. CONCLUSIONS: Although LRC presented perioperative benefits compared to ORC, the results were better after the implementation of an ERAS protocol. ERAS protocol had stronger impact on recovery than the surgical approach of the procedure.

Robust nondimensional estimators to assess the nasal airflow in health and disease.

There are significant variations of both human nose shapes and airflow patterns inside nasal cavities, so it is difficult to provide a comprehensive medical identification using a universal template for what otolaryngologists consider normal breathing at rest. In addition, airflow patterns present even more random characteristics in diseased nasal cavities. To give a medical assessment to differentiate the nasal cavities in health and disease, we propose 2 nondimensional estimators obtained from both medical images and computational fluid dynamics. The first mathematical estimator ϕ is a function of geometric features and potential asymmetries between nasal passages, while the second estimator R represents in fluid mechanics terms the total nasal resistance that corresponds to the atmosphere-choana pressure drop. These estimators only require global information such as nasal geometry and magnitudes of flow determined by simulations under laminar conditions. We find that these estimators take low and high values for healthy and diseased nasal cavities, respectively. Our study, based on 24 healthy and 25 diseased Caucasian subjects, reveals that there is an interval of values associated with healthy cavities that clusters in a small region of the plane ϕ-R. Therefore, these estimators can be seen as a first approximation to provide nasal airflow data to the clinician in a noninvasive method, as the computed tomography scan that provides the required images is routinely obtained as a result of the preexisting naso-sinusal condition.

Apendicectomía laparoscópica versus cirugía abierta para la apendicitis complicada / Laparoscopic versus open appendectomy for complicated appendicitis

INTRODUCCIÓN El tratamiento de la apendicitis aguda por vía laparoscópica reduce el riesgo de infección de la herida operatoria, disminuye el tiempo de hospitalización y acelera el retorno a las actividades. Sin embargo, aumenta el riesgo de infecciones intraabdominales, lo cual constituye uno de las principales riesgos del tratamiento quirúrgico laparoscópico de la apendicitis complicada. MÉTODOS Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos seis revisiones sistemáticas que en conjunto incluyen 55 estudios primarios, de los cuales, cuatro corresponden a ensayos aleatorizados. Concluimos que la laparoscopía, en comparación con la cirugía abierta, probablemente disminuye el tiempo de estadía hospitalaria, y podría disminuir el riesgo de infección de la herida operatoria, pero no está claro si existen diferencias en la incidencia de absceso intraabdominal porque la certeza de la evidencia es muy baja.

INTRODUCTION The treatment of acute appendicitis using laparoscopy reduces the risk of wound infection, hospitalization time and return to normal activity. However, it increases the risk of intra-abdominal abscess, which is one the main complications of complicated appendicitis. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified six systematic reviews including 55 studies overall, of which four were randomized trials. We concluded that the used of laparoscopy, compared to open appendectomy, probably reduces the time of hospital stay, and may reduce the risk of wound infection, but there's no clarity regarding the incidence of intra-abdominal abscess due to the very low certainty of the evidence available.

Cavitation in a lubrication flow between a moving sphere and a boundary.

A heavy sphere is free to move inside a rotating horizontal cylinder filled with viscous liquid. The steady motion is essentially Stokesian, and the sphere rotates at a fixed location with a lubrication layer between the ball and the wall. The symmetry of the flow field suggests there will be no force to balance the normal component of the ball's weight. However, we show that a normal force can arise when a cavitation bubble is present. The bubble size was measured as a function of the cylinder rotation rate and agrees well with a model which uses the force and torque balances on the sphere.

[Psychologic iatrogenic disease in the postsurgical child]. / Iatrogenia psicológica en el niño postquirúrgico.

In the present paper, we comment on the psychological and emotional disorders occurring after surgery. We surveyed 150 children that were admitted in several surgical units of our Children's Hospital. We used the Vernon's test in a questionaire. We reached a high level of comprehension. As a result, 121 valid questionaires were returned. The considerable amount of information was statistically studied with a computer, obtaining data on the following aspects: Filiation, frequency and percentage of every answer. Post-hospitalization behaviour evaluated by Vernon's test. Partial and total results under the 6 factors of the questionaire: General anxiety and regression, anxiety about separation, anxiety about sleeping, eating disturbances, agressiveness against authority, apathy and isolation. Previous results in connection with the diverse filiation variables. When we analyzed the results, we confirmed the findings of other investigators: A global damage in child behaviour, that is present in two main aspects: "Anxiety about separation" and "Agressiveness against authority". In conclusion, our results support the need for implementing prophylactic measures, of which "psychological presentation" is the most important, to children that are going to be operated upon.