Association of Kidney Stone Disease (KSD) with Primary Gastrointestinal Surgery: a Systematic Review over Last 2 Decades.

PURPOSE OF REVIEW: We aim to provide an up-to-date literature review to further characterise the association of kidney stone disease (KSD) with gastrointestinal (GI) surgery. As KSD is associated with significant morbidity, it is important to quantify and qualify this association to provide better care and management for the patient subgroup. OBJECTIVE: To perform a systematic review of the existing literature to evaluate the association of KSD following GI surgery. METHODS: A literature search was performed of the following databases: MEDLINE, EMBASE, Scopus, Google Scholar, Key Urology, Uptodate and Cochrane Trials from January 2000 to June 2020. RECENT FINDINGS: A total of 106 articles were identified, and after screening for titles, abstracts and full articles, 12 full papers were included. This involved a total of 9299 patients who underwent primary GI surgery. Over a mean follow-up period of 5.4 years (range: 1-14.4 years), 819 (8.8%) developed KSD, varying from 1.2 to 83% across studies. The mean time to stone formation was approximately 3 years (range: 0.5-9 years). In the 4 studies that reported on the management of KSD (n = 427), 38.6% went on to have urological intervention. There is a high incidence of KSD following primary GI surgery, and after a mean follow-up of 3 years, around 9% of patients developed KSD. While the GI surgery was done for obesity, inflammatory bowel disease or cancer, the risk of KSD should be kept in mind during follow-up, and prompt urology involvement with metabolic assessment, medical and or surgical management offered as applicable.

The use of throat packs in ear, nose and throat, oral and dental surgery: a systematic review.

BACKGROUND: Throat packs are placed around the airway in patients undergoing upper airway surgical procedures under general anaesthetic to prevent aspiration or ingestion of blood, and consequent chest infections or postoperative nausea and vomiting (PONV). There is no definitive evidence for this, and each time a pack is placed, it risks being retained and obstructing the upper airway. This study aimed to determine whether throat packs are of benefit to patients undergoing upper airway surgical procedures. METHODS: Medline, Embase and Central were searched from conception to 15th January 2018 using individualised search strategies. A systematic search of multiple databases was undertaken using custom strategies to identify all relevant randomised controlled trials. Screening, risk of bias assessment and data extraction were undertaken independently by two authors. Primary outcomes included throat pain and PONV. Secondary outcomes included any adverse event documented. RESULTS: Thirteen papers were eligible for inclusion. No studies reported any instances of retained throat packs. Ten studies assessed the effect of throat packs on post-operative throat pain, with four papers showing a significantly higher incidence of pain when throat packs were used. One study showed throat pain to be slightly, but significantly, worse 24 hours post-surgery when a pack was not used. No paper showed throat packs to be of benefit in preventing PONV. CONCLUSION: The study was limited by methodological flaws of included trials, overall relatively low numbers of patients and difficulty in contacting authors to clarify information and obtain raw data. However, this systematic review found no evidence to support the use of throat packs. This supports the proposal that there is no indication for the routine use of throat packs in ENT, maxillofacial and dental procedures.

Prediction of pre-eclampsia: review of reviews.

OBJECTIVE: Primary studies and systematic reviews provide estimates of varying accuracy for different factors in the prediction of pre-eclampsia. The aim of this study was to review published systematic reviews to collate evidence on the ability of available tests to predict pre-eclampsia, to identify high-value avenues for future research and to minimize future research waste in this field. METHODS: MEDLINE, EMBASE and The Cochrane Library including DARE (Database of Abstracts of Reviews of Effects) databases, from database inception to March 2017, and bibliographies of relevant articles were searched, without language restrictions, for systematic reviews and meta-analyses on the prediction of pre-eclampsia. The quality of the included reviews was assessed using the AMSTAR tool and a modified version of the QUIPS tool. We evaluated the comprehensiveness of search, sample size, tests and outcomes evaluated, data synthesis methods, predictive ability estimates, risk of bias related to the population studied, measurement of predictors and outcomes, study attrition and adjustment for confounding. RESULTS: From 2444 citations identified, 126 reviews were included, reporting on over 90 predictors and 52 prediction models for pre-eclampsia. Around a third (n = 37 (29.4%)) of all reviews investigated solely biochemical markers for predicting pre-eclampsia, 31 (24.6%) investigated genetic associations with pre-eclampsia, 46 (36.5%) reported on clinical characteristics, four (3.2%) evaluated only ultrasound markers and six (4.8%) studied a combination of tests; two (1.6%) additional reviews evaluated primary studies investigating any screening test for pre-eclampsia. Reviews included between two and 265 primary studies, including up to 25 356 688 women in the largest review. Only approximately half (n = 67 (53.2%)) of the reviews assessed the quality of the included studies. There was a high risk of bias in many of the included reviews, particularly in relation to population representativeness and study attrition. Over 80% (n = 106 (84.1%)) summarized the findings using meta-analysis. Thirty-two (25.4%) studies lacked a formal statement on funding. The predictors with the best test performance were body mass index (BMI) > 35 kg/m2 , with a specificity of 92% (95% CI, 89-95%) and a sensitivity of 21% (95% CI, 12-31%); BMI > 25 kg/m2 , with a specificity of 73% (95% CI, 64-83%) and a sensitivity of 47% (95% CI, 33-61%); first-trimester uterine artery pulsatility index or resistance index > 90th centile (specificity 93% (95% CI, 90-96%) and sensitivity 26% (95% CI, 23-31%)); placental growth factor (specificity 89% (95% CI, 89-89%) and sensitivity 65% (95% CI, 63-67%)); and placental protein 13 (specificity 88% (95% CI, 87-89%) and sensitivity 37% (95% CI, 33-41%)). No single marker had a test performance suitable for routine clinical use. Models combining markers showed promise, but none had undergone external validation. CONCLUSIONS: This review of reviews calls into question the need for further aggregate meta-analysis in this area given the large number of published reviews subject to the common limitations of primary predictive studies. Prospective, well-designed studies of predictive markers, preferably randomized intervention studies, and combined through individual-patient data meta-analysis are needed to develop and validate new prediction models to facilitate the prediction of pre-eclampsia and minimize further research waste in this field. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Predicción de la preeclampsia: revisión de revisiones OBJETIVO: Los estudios primarios y las revisiones sistemáticas proporcionan estimaciones de precisión variable para diferentes factores en la predicción de la preeclampsia. El objetivo de este estudio fue revisar las revisiones sistemáticas publicadas para recopilar evidencia sobre la capacidad de las pruebas disponibles para predecir la preeclampsia, identificar avenidas de investigación futura valiosas y minimizar el desperdicio futuro de investigación en este campo. MÉTODOS: Se realizaron búsquedas de artículos relevantes en bibliografías sobre el tema y en las bases de datos MEDLINE, EMBASE y The Cochrane Library, incluida DARE (Database of Abstracts of Reviews of Effects), desde el inicio de cada base de datos hasta marzo de 2017, sin restricciones de idioma, para obtener revisiones sistemáticas y metaanálisis sobre la predicción de la preeclampsia. La calidad de las revisiones incluidas se evaluó utilizando la herramienta AMSTAR y una versión modificada de la herramienta QUIPS. Se evaluó la amplitud de la búsqueda, el tamaño de la muestra, las pruebas y los resultados evaluados, los métodos de síntesis de datos, las estimaciones de la capacidad de predicción, el riesgo de sesgo relacionado con la población estudiada, la medición de los predictores y los resultados, la deserción del estudio y el ajuste por confusión. RESULTADOS: De las 2444 citas identificadas, se incluyeron 126 revisiones, que informaron sobre más de 90 predictores y 52 modelos de predicción para la preeclampsia. Alrededor de un tercio (n=37 (29,4%)) de todas las revisiones investigaron únicamente marcadores bioquímicos para predecir la preeclampsia, 31 (24,6%) investigaron asociaciones genéticas con la preeclampsia, 46 (36,5%) informaron sobre las características clínicas, cuatro (3,2%) evaluaron sólo marcadores ecográficos y seis (4,8%) estudiaron una combinación de pruebas; dos (1,6%) revisiones adicionales evaluaron los estudios primarios que investigaron cualquier prueba de diagnóstico de la preeclampsia. Las revisiones incluyeron entre dos y 265 estudios primarios, que incluyeron hasta 25 356 688 mujeres en la revisión más grande. Sólo aproximadamente la mitad (n=67 (53,2%)) de las revisiones evaluaron la calidad de los estudios incluidos. En muchas de las revisiones incluidas hubo un alto riesgo de sesgo, particularmente en relación con la representatividad de la población y la deserción de los estudios. Más del 80% (n=106 (84,1%)) resumió los hallazgos utilizando el metaanálisis. Treinta y dos (25,4%) estudios carecían de una declaración formal sobre la financiación. Los predictores con el mejor rendimiento de la prueba fueron el índice de masa corporal (IMC) >35 kg.m-2 , con una especificidad del 92% (IC 95%, 89-95%) y una sensibilidad del 21% (IC 95%, 12-31%); IMC >25 kg.m-2 , con una especificidad del 73% (IC 95%: 64-83%) y una sensibilidad del 47% (IC 95%: 33-61%); índice de pulsatilidad de la arteria uterina en el primer trimestre o índice de resistencia >90° percentil (especificidad del 93% (IC 95%: 90-96%) y sensibilidad del 26% (IC 95%: 23-31%)); factor de crecimiento placentario (especificidad 89% (IC 95%, 89-89%) y sensibilidad 65% (IC 95%, 63-67%)); y proteína placentaria 13 (especificidad 88% (IC 95%, 87-89%) y sensibilidad 37% (IC 95%, 33-41%)). Ningún marcador por sí solo tuvo un rendimiento de la prueba adecuado para el uso clínico rutinario. Los modelos que combinan marcadores son prometedores, pero ninguno fue sometido a una validación externa. CONCLUSIONES: Esta revisión de revisiones ha puesto en duda la necesidad de un metaanálisis agregado adicional en esta área, dado el gran número de revisiones publicadas sujetas a las limitaciones comunes de los estudios predictivos primarios. Se necesitan estudios prospectivos bien diseñados de marcadores predictivos, preferiblemente en estudios de intervención aleatorios, y combinados mediante el metaanálisis de datos de pacientes individuales, para desarrollar y validar nuevos modelos predictivos que faciliten la predicción de la preeclampsia y minimicen el desperdicio de investigación adicional en este campo.

Biomechanical characterisation of the human nasal cartilages; implications for tissue engineering.

Nasal reconstruction is currently performed using autologous grafts provides but is limited by donor site morbidity, tissue availability and potentially graft failure. Additionally, current alternative alloplastic materials are limited by their high extrusion and infection rates. Matching mechanical properties of synthetic materials to the native tissue they are replacing has shown to be important in the biocompatibility of implants. To date the mechanical properties of the human nasal cartilages has not been studied in depth to be able to create tissue-engineered replacements with similar mechanical properties to native tissue. The young's modulus was characterized in compression on fresh-frozen human cadaveric septal, alar, and lateral cartilage. Due to the functional differences experienced by the various aspects of the septal cartilage, 16 regions were evaluated with an average elastic modulus of 2.72 ± 0.63 MPa. Furthermore, the posterior septum was found to be significantly stiffer than the anterior septum (p < 0.01). The medial and lateral alar cartilages were tested at four points with an elastic modulus ranging from 2.09 ± 0.81 MPa, with no significant difference between the cartilages (p < 0.78). The lateral cartilage was tested once in all cadavers with an average elastic modulus of 0.98 ± 0.29 MPa. In conclusion, this study provides new information on the compressive mechanical properties of the human nasal cartilage, allowing surgeons to have a better understanding of the difference between the mechanical properties of the individual nasal cartilages. This study has provided a reference, by which tissue-engineered should be developed for effective cartilage replacements for nasal reconstruction.

Morphometric characterisation of human tracheas: focus on cartilaginous ring variation.

PURPOSE: Details regarding tracheal anatomy are currently lacking, with existing literature focussing mainly on the cricoid-tracheal region or the carina. External gross anatomy and internal morphology throughout the entire trachea is important for normal physiological functioning and various clinical applications such as designs for tracheal implants or endotracheal devices. OBJECTIVE: To determine quantitative and qualitative characteristics of gross tracheal and individual tracheal ring anatomy. METHOD: 10 tracheas were harvested from formaldehyde-fixed cadavers. Tracheal length, height and inter-ring distance were measured from complete tracheas. Individual rings were excised and the following measurements were taken at three points on the ring: thickness, width, and antero-posterior (A-P) length. RESULTS: The average tracheal length was 10.38 ± 0.85 cm with a mean of 19 ± 3 rings per trachea. The average width and A-P diameter of tracheal lumens were 17.31 ± 2.57 and 17.27 ± 2.56 mm, with a width-AP ratio of 1.00 ('C' shaped ring). The A-P diameter shows a trend of narrowing slightly from the upper 1/3 to the lower 1/3 of the trachea. While majority of tracheal rings consisted of the expected 'C' shape, more than 41% of the 147 counted rings consisted of abnormally shaped rings which were further analysed. CONCLUSION: This study provides further details regarding tracheal anatomy which will be useful for implant design. Of interest for anatomists, is the marked variability in tracheal ring morphology which could be further characterised in larger studies.

Comparison of the mechanical properties of different skin sites for auricular and nasal reconstruction.

BACKGROUND: Autologous and synthetic nasal and auricular frameworks require skin coverage. The surgeon's decides on the appropriate skin coverage for reconstruction based on colour matching, subcutaneous tissue thickness, expertise and experience. One of the major complications of placing subcutaneous implants is the risk of extrusion (migration through the skin) and infection. However, knowledge of lessening the differential between the soft tissue and the framework can have important implications for extrusion. This study compared the mechanical properties of the skin commonly used as skin sites for the coverage in auricular and nasal reconstruction. METHODS: Using ten fresh human cadavers, the tensile Young's Modulus of the skin from the forehead, forearm, temporoparietal, post-auricular and submandibular neck was assessed. The relaxation rate and absolute relaxation level was also assessed after 90 min of relaxation. RESULTS: The submandibular skin showed the greatest Young's elastic modulus in tension of all regions (1.28 MPa ±0.06) and forearm showed the lowest (1.03 MPa ±0.06). The forehead demonstrated greater relaxation rates among the different skin regions (7.8 MPa-07 ± 0.1). The forearm showed the lowest rate of relaxation (4.74 MPa-07 ± 0.1). The forearm (0.04 MPa ±0.004) and submandibular neck skin (0.04 MPa ±0.005) showed similar absolute levels of relaxation, which were significantly greater than the other skin regions (p < 0.05). CONCLUSIONS: This study provides an understanding into the biomechanical properties of the skin of different sites allowing surgeons to consider this parameter when trying to identify the optimal skin coverage in nasal and auricular reconstruction.

Biomechanical Characterisation of the Human Auricular Cartilages; Implications for Tissue Engineering.

Currently, autologous cartilage provides the gold standard for auricular reconstruction. However, synthetic biomaterials offer a number of advantages for ear reconstruction including decreased donor site morbidity and earlier surgery. Critical to implant success is the material's mechanical properties as this affects biocompatibility and extrusion. The aim of this study was to determine the biomechanical properties of human auricular cartilage. Auricular cartilage from fifteen cadavers was indented with displacement of 1 mm/s and load of 300 g to obtain a Young's modulus in compression. Histological analysis of the auricle was conducted according to glycoprotein, collagen, and elastin content. The compression modulus was calculated for each part of the auricle with the tragus at 1.67 ± 0.61 MPa, antitragus 1.79 ± 0.56 MPa, concha 2.08 ± 0.70 MPa, antihelix 1.71 ± 0.63 MPa, and helix 1.41 ± 0.67 MPa. The concha showed to have a significantly greater Young's Elastic Modulus than the helix in compression (p < 0.05). The histological analysis demonstrated that the auricle has a homogenous structure in terms of chondrocyte morphology, extracellular matrix and elastin content. This study provides new information on the compressive mechanical properties and histological analysis of the human auricular cartilage, allowing surgeons to have a better understanding of suitable replacements. This study has provided a reference, by which cartilage replacements should be developed for auricular reconstruction.