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Saudi Journal of Anaesthesia 2023Elderly patients have a high risk of perioperative morbidity and mortality. Pluri-morbidities, polypharmacy, and functional dependence may have a great impact on... (Review)
Review
Elderly patients have a high risk of perioperative morbidity and mortality. Pluri-morbidities, polypharmacy, and functional dependence may have a great impact on intraoperative management and request specific cautions. In addition to surgical stress, several perioperative noxious stimuli such as fasting, blood loss, postoperative pain, nausea and vomiting, drug adverse reactions, and immobility may trigger a derangement leading to perioperative complications. Older patients have a high risk of major hemodynamic derangement due to aging of the cardiovascular system and associated comorbidities. The hemodynamic monitoring as well as fluid therapy should be the most accurate as possible. Aging is accompanied by decreased renal function, which is related to a reduction in renal blood flow, renal mass, and the number and size of functioning nephrons. Drugs eliminated predominantly by the renal route need dosage adjustments based on residual renal function. Liver mass, hepatic blood flow, and intrinsic metabolic activity are decreased in the elderly, and all drugs metabolized by the liver have a variable half-life, thus requiring dose reduction. Decreased neural plasticity contributes to a high risk for postoperative delirium. Monitoring of anesthesia depth should be mandatory to avoid overdosage of hypnotic drugs. Prevention of postoperative pulmonary complications requires both protective ventilation strategies and adequate recovery of neuromuscular function at the end of surgery. Avoidance of hypothermia cannot be missed. The aim of this review is to describe comprehensive strategies for intraoperative management plans tailored to meet the unique needs of elderly surgical patients, thus improving outcomes in this vulnerable population.
PubMed: 37779561
DOI: 10.4103/sja.sja_579_23 -
Nature Reviews. Nephrology Jul 2021Complex multicellular life in mammals relies on functional cooperation of different organs for the survival of the whole organism. The kidneys play a critical part in... (Review)
Review
Complex multicellular life in mammals relies on functional cooperation of different organs for the survival of the whole organism. The kidneys play a critical part in this process through the maintenance of fluid volume and composition homeostasis, which enables other organs to fulfil their tasks. The renal endothelium exhibits phenotypic and molecular traits that distinguish it from endothelia of other organs. Moreover, the adult kidney vasculature comprises diverse populations of mostly quiescent, but not metabolically inactive, endothelial cells (ECs) that reside within the kidney glomeruli, cortex and medulla. Each of these populations supports specific functions, for example, in the filtration of blood plasma, the reabsorption and secretion of water and solutes, and the concentration of urine. Transcriptional profiling of these diverse EC populations suggests they have adapted to local microenvironmental conditions (hypoxia, shear stress, hyperosmolarity), enabling them to support kidney functions. Exposure of ECs to microenvironment-derived angiogenic factors affects their metabolism, and sustains kidney development and homeostasis, whereas EC-derived angiocrine factors preserve distinct microenvironment niches. In the context of kidney disease, renal ECs show alteration in their metabolism and phenotype in response to pathological changes in the local microenvironment, further promoting kidney dysfunction. Understanding the diversity and specialization of kidney ECs could provide new avenues for the treatment of kidney diseases and kidney regeneration.
Topics: Adaptation, Physiological; Endothelial Cells; Endothelium, Vascular; Humans; Kidney; Kidney Diseases; Oxygen; Phenotype; Stress, Mechanical
PubMed: 33767431
DOI: 10.1038/s41581-021-00411-9 -
Pediatric Nephrology (Berlin, Germany) Nov 2021Genetic studies of hereditary nephrotic syndrome (NS) have identified more than 50 genes that, if mutated, are responsible for monogenic forms of steroid-resistant NS... (Review)
Review
Genetic studies of hereditary nephrotic syndrome (NS) have identified more than 50 genes that, if mutated, are responsible for monogenic forms of steroid-resistant NS (SRNS), either isolated or syndromic. Most of these genes encode proteins expressed in the podocyte with various functions such as transcription factors, mitochondrial proteins, or enzymes, but mainly structural proteins of the slit diaphragm (SD) as well as cytoskeletal binding and regulator proteins. Syndromic NS is sometimes associated with neurological features. Over recent decades, various studies have established links between the physiology of podocytes and neurons, both morphologically (slit diaphragm and synapse) and functionally (signaling platforms). Variants in genes expressed in different compartments of the podocyte and neurons are responsible for phenotypes associating kidney lesions with proteinuria (mainly Focal and Segmental Glomerulosclerosis (FSGS) or Diffuse Mesangial Sclerosis (DMS)) and central and/or peripheral neurological disorders. The Galloway-Mowat syndrome (GAMOS, OMIM#251300) associates neurological defects, microcephaly, and proteinuria and is caused by variants in genes encoding proteins of various functions (microtubule cytoskeleton regulation (WDR73), regulation of protein synthesis via transfer RNAs (KEOPS and WDR4 complexes)). Pierson syndrome (OMIM#609049) associating congenital nephrotic syndrome and central neurological and ophthalmological anomalies is secondary to variants in LAMB2, involved in glomerular and ocular basement membranes. Finally, Charcot-Marie-Tooth-FSGS (OMIM#614455) combines peripheral sensory-motor neuropathy and proteinuria and arises from INF2 variants, resulting in cytoskeletal polymerization defects. This review focuses on genetic syndromes associating nephrotic range proteinuria and neurological involvement and provides the latest advances in the description of these neuro-renal disorders.
Topics: Humans; Nephrotic Syndrome; Proteinuria
PubMed: 33791874
DOI: 10.1007/s00467-020-04903-x -
Nature Communications Sep 2023The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear....
The host-microbiota co-metabolite trimethylamine N-oxide (TMAO) is linked to increased cardiovascular risk but how its circulating levels are regulated remains unclear. We applied "explainable" machine learning, univariate, multivariate and mediation analyses of fasting plasma TMAO concentration and a multitude of phenotypes in 1,741 adult Europeans of the MetaCardis study. Here we show that next to age, kidney function is the primary variable predicting circulating TMAO, with microbiota composition and diet playing minor, albeit significant, roles. Mediation analysis suggests a causal relationship between TMAO and kidney function that we corroborate in preclinical models where TMAO exposure increases kidney scarring. Consistent with our findings, patients receiving glucose-lowering drugs with reno-protective properties have significantly lower circulating TMAO when compared to propensity-score matched control individuals. Our analyses uncover a bidirectional relationship between kidney function and TMAO that can potentially be modified by reno-protective anti-diabetic drugs and suggest a clinically actionable intervention for decreasing TMAO-associated excess cardiovascular risk.
Topics: Adult; Humans; Causality; Methylamines; Endocrinology; Kidney
PubMed: 37730687
DOI: 10.1038/s41467-023-39824-4 -
World Journal of Urology May 2020The role of robotic partial nephrectomy (RPN) is becoming increasingly prevalent in managing small renal masses. Renal functional outcomes have been reported with... (Review)
Review
PURPOSE
The role of robotic partial nephrectomy (RPN) is becoming increasingly prevalent in managing small renal masses. Renal functional outcomes have been reported with relation to the amount of healthy renal parenchyma resected and ischemia time; however, there is limited data on the effect of renorrhaphy on long-term renal function. Our aim is to evaluate the impact of renorrhaphy technique on renal functional outcomes.
METHODS
A nonsystematic literature review was performed to retrieve articles assessing renorrhaphy techniques and renal function outcomes, specifically focusing on single-layer vs. traditional two-layer renorrhaphy.
RESULTS
Performing single-layer renorrhaphy while omitting cortical renorrhaphy appears to improve renal function postoperatively, based on very limited studies in the literature that were evaluated.
CONCLUSION
Single-layer renorrhaphy may be associated with improved postoperative renal function and could prove to be useful in patients with chronic renal insufficiency or solitary kidney. The ongoing clinical trial NCT02131376 may provide further information on the impact of renorrhaphy technique on long-term renal function.
Topics: Glomerular Filtration Rate; Humans; Kidney; Kidney Neoplasms; Nephrectomy; Robotic Surgical Procedures; Suture Techniques; Tumor Burden
PubMed: 31792576
DOI: 10.1007/s00345-019-03033-w -
Nature Reviews. Urology Dec 2023Evolution of the vertebrate urinary system occurs in response to numerous selective pressures, which have been incompletely characterized. Developing research into... (Review)
Review
Evolution of the vertebrate urinary system occurs in response to numerous selective pressures, which have been incompletely characterized. Developing research into urinary evolution led to the occurrence of clinical applications and insights in paediatric urology, reproductive medicine, urolithiasis and other domains. Each nephron segment and urinary organ has functions that can be contextualized within an evolutionary framework. For example, the structure and function of the glomerulus and proximal tubule are highly conserved, enabling blood cells and proteins to be retained, and facilitating the elimination of oceanic Ca and Mg. Urea emerged as an osmotic mediator during evolution, as cells of large organisms required increased precision in the internal regulation of salinity and solutes. As the first vertebrates moved from water to land, acid-base regulation was shifted from gills to skin and kidneys in amphibians. In reptiles and birds, solute regulation no longer occurred through the skin but through nasal salt glands and post-renally, within the cloaca and the rectum. In placental mammals, nasal salt glands are absent and the rectum and urinary tracts became separate, which limited post-renal urine concentration and led to the necessity of a kidney capable of high urine concentration. Considering the evolutionary and environmental selective pressures that have contributed to renal evolution can help to gain an increased understanding of renal physiology.
Topics: Female; Humans; Pregnancy; Animals; Child; Placenta; Vertebrates; Kidney; Reptiles; Birds; Mammals
PubMed: 37443264
DOI: 10.1038/s41585-023-00794-3 -
International Journal of Molecular... Dec 2022The renal condition is one of the crucial predictors of longevity; therefore, early diagnosis of any dysfunction plays an important role. Kidneys are highly susceptible... (Review)
Review
The renal condition is one of the crucial predictors of longevity; therefore, early diagnosis of any dysfunction plays an important role. Kidneys are highly susceptible to the aging process. Unfavorable conditions may lead to a significant disturbance of the body's homeostasis. Apart from physiological changes, there are some conditions such as hypertension, diabetes or obesity which contribute to the acceleration of the aging process. A determination of macroscopic and microscopic changes is essential for assessing the progression of aging. With age, we observe a decrease in the volume of renal parenchyma and an increase in adipose tissue in the renal sinuses. Senescence may also be manifested by the roughness of the kidney surface or simple renal cysts. The main microscopic changes are a thickening of the glomerular basement membrane, nephrosclerosis, an accumulation of extracellular matrix, and mesangial widening. The principal aspect of stopping unfavorable changes is to maintain health. Studies have shown many useful ways to mitigate renal aging. This review is focused especially on medications such as renin-angiotensin-aldosterone system blockers or resveratrol, but even eating habits and lifestyle.
Topics: Humans; Kidney; Nephrosclerosis; Kidney Diseases; Aging; Hypertension; Glomerular Filtration Rate
PubMed: 36499760
DOI: 10.3390/ijms232315435 -
Pediatric Radiology Feb 2022The goal of functional renal imaging is to identify and quantitate irreversible renal damage and nephron loss, as well as potentially reversible hemodynamic changes. MR... (Review)
Review
The goal of functional renal imaging is to identify and quantitate irreversible renal damage and nephron loss, as well as potentially reversible hemodynamic changes. MR urography has evolved into a comprehensive evaluation of the urinary tract that combines anatomical imaging with functional evaluation in a single test without ionizing radiation. Quantitative functional MR imaging is based on dynamic contrast-enhanced MR acquisitions that provide progressive, visible enhancement of the renal parenchyma and urinary tract. The signal changes related to perfusion, concentration and excretion of the contrast agent can be evaluated using both quantitative and qualitative measures. Functional evaluation with MR has continued to improve as a result of significant technical advances allowing for faster image acquisition as well as the development of new tracer kinetic models of renal function. The most common indications for MR urography in children are the evaluation of congenital anomalies of the kidney and urinary tract including hydronephrosis and renal malformations, and the identification of ectopic ureters in children with incontinence. In this paper, we review the underlying acquisition schemes and techniques used to generate quantitative functional parameters including the differential renal function (DRF), asymmetry index, mean transit time (MTT), signal intensity versus time curves as well as the calculation of individual kidney glomerular filtration rate (GFR). Visual inspection and semi-quantitative assessment using the renal transit time (RTT) and calyceal transit times (CTT) are fundamental to accurate diagnosis and are used as a basis for the interpretation of the quantitative data. The importance of visual assessment of the images cannot be overstated when analyzing the quantitative measures of renal function.
Topics: Child; Humans; Kidney; Kidney Pelvis; Magnetic Resonance Imaging; Magnetic Resonance Spectroscopy; Urography
PubMed: 35022851
DOI: 10.1007/s00247-021-05264-9 -
The Urologic Clinics of North America May 2023Knowledge of functional recovery after partial (PN) and radical nephrectomy for renal cancer has advanced considerably, with PN now established as the reference standard... (Review)
Review
Knowledge of functional recovery after partial (PN) and radical nephrectomy for renal cancer has advanced considerably, with PN now established as the reference standard for most localized renal masses. However, it is still unclear whether PN provides an overall survival benefit in patients with a normal contralateral kidney. While early studies seemingly demonstrated the importance of minimizing warm-ischemia time during PN, multiple new investigations over the last 10 years have proven that parenchymal mass lost is the most important predictor of new baseline renal function. Minimizing loss of parenchymal mass during resection and reconstruction is the most important controllable aspect of long-term post-operative renal function preservation.
Topics: Humans; Kidney; Kidney Neoplasms; Carcinoma, Renal Cell; Nephrectomy; Warm Ischemia
PubMed: 36948670
DOI: 10.1016/j.ucl.2023.01.004