Channel Your Enthusiasm

Chapter Nineteen, Part 1: Metabolic Acidosis, The Show

References Chapter 19, Part 1 Metabolic acidosis June 14, 2023 American Society of Nephrology | Medical Students - Kidney TREKS this is the program that Josh mentioned at Mount Desert Island! Effects of pH on Potassium: New Explanations for Old Observations - PMC here’s the review melanie from Peter Aronson that clarifies the fact that there are no H+-K+ antiporters outside the kidney but rather coupled transport- We discussed whether we like “Winter’s formula” Quantitative Displacement of Acid-...

Chapter Eighteen, part 1

We are a bit slappy at the beginning of the episode since we had just recorded our conversation with the Glaucomfleckens . References Chapter 18 Metabolic alkalosis! Part 1 February 23, 2023 It is chloride depletion alkalosis, not contraction alkalosis classic review by Galla and Luke, the metabolic alkalosis mavens who review the role of chloride. On the mechanism by which chloride corrects metabolic alkalosis in man and this is the study when they induced a metabolic alkalosis and studied the ...

Chapter Seventeen

References I said I used MDCalc but I was mistaken I use MedCalX which is nice but getting dated. We talked about this out of print book that we love: Cohen, J. J., Kassirer, J. P. (1982). Acid-base. United States: Little, Brown. Josh mentioned this article that looked at over 17,000 samples with simultaneous measured and calculated bicarbonate and found a very small difference. Comparison of Measured and Calculated Bicarbonate Values | Clinical Chemistry | Oxford Academic Base deficit or excess...

Chapter Sixteen, part 2

References We talked about winning the 2022 ASN innovation contest and here’s a link to our promo video https://www.dropbox.com/scl/fi/g4osnf0nradsfryyo51fi/ASN-Education-Contest-Channel-Your-Enthusiasm-Podcast.mp4?rlkey=pnso45x07nr3pane9y8cux8yg&e=1&dl=0 We wondered about “permissive hypercreatinemia” and Josh referenced the DOSE trial: Relevance of Changes in Serum Creatinine During a Heart Failure Trial of Decongestive Strategies: Insights From the DOSE Trial - PMC Plus this editorial...

Chapter Sixteen, part 1

References Capillary Hemodynamics Insights into Salt Handling and Blood Pressure | NEJM Amy mentioned about the 3 phases of the interstitium Are the precapillary sphincters and metarterioles universal components of the microcirculation? An historical review - PMC Safety factor? Renal Function during Recovery from Minimal Lesions Nephrotic Syndrome - Abstract - Nephron 1987, Vol. 47, No. 3 - Karger Publishers Are diuretics effective for idiopathic lymphedema? : Evidence-Based Practice Rapid diure...

Chapter Fifteen, part 2: Clinical Use of Diuretics

References Proximal Tubule-Specific Deletion of the NHE3 (Na+/H+ Exchanger 3) in the Kidney Attenuates Ang II (Angiotensin II)-Induced Hypertension in Mice Melanie is in love with this paper that shows that sodium retention Bumetanide and furosemide in heart failure everyone agreed that we love this classic paper from Craig Brater on diuretics (and the source of figure 15-6). Lety referenced the Cr x 20 formula, a strategy to multiply the serum creatinine by 20 to estimate the initial furosemide...

Chapter Fifteen, part 1: Clinical Use of Diuretics

Outline Chapter 15 — Clinical Use of Diuretics - Among most commonly used drugs - Block NaCl reabsorption at different sites along the nephron - The ability to induce negative balance has made them useful in multiple diseases - Edematous states - Hypertension - Mechanism of action - Three major classes - Loop - NaK2Cl - Up to 25% of filtered sodium excreted - Thiazide - NCC - Up to 3-5% of filtered sodium excreted - Potassium sparing - ENaC - Up to 1-2% of filtered sodium excreted - Each segment...

Chapter Fourteen, part 2. Hypovolemic States

Outline Chapter 14 — Treatment - Treatment - Both oral and IV treatment can be used for volume replacement - The goal of therapy are to restore normovolemia - And to correct associated acid-base and electrolyte disorders - Oral Therapy - Usually can be accomplished with increased water and dietary sodium - May use salt tablets - Glucose often added to resuscitation fluids - Provides calories - Promotes intestinal Na reabsorption since there is coupled Na and Glucose similar to that seen in the p...

Chapter Fourteen, part 1. Hypovolemic States

Outline Chapter 14 - Hypovolemic States - Etiology - True volume depletion occurs when fluid is lost from from the extracellular fluid at a rate exceeding intake - Can come the GI tract - Lungs - Urine - Sequestration in the body in a “third space” that is not in equilibrium with the extracellular fluid. - When losses occur two responses ameliorate them - Our intake of Na and fluid is way above basal needs - This is not the case with anorexia or vomiting - The kidney responds by minimizing furth...

Chapter Thirteen Meaning and Application of Urine Chemistries

References JC mentioned that the diagnostic accuracy of 24 hour urine collection increases with more collections! Metabolic evaluation of patients with recurrent idiopathic calcium nephrolithiasis We didn't refer to a particular study on sodium intake and the 24 hour urine but this meta-analysis Comparison of 24‐hour urine and 24‐hour diet recall for estimating dietary sodium intake in populations: A systematic review and meta‐analysis - PMC 24‐hour diet recall underestimated population mean sod...

Chapter Eleven, part 2: Regulation of Acid-Base Balance

References We considered the complexity of the machinery to excrete ammonium in the context of research on dietary protein and how high protein intake may increase glomerular pressure and contribute to progressive renal disease (many refer to this as the “Brenner hypothesis”). Dietary protein intake and the progressive nature of kidney disease: the role of hemodynamically mediated glomerular injury in the pathogenesis of progressive glomerular sclerosis in aging, renal ablation, and intrinsic re...

The 2023 NKF Clinical Meeting Live Recording: Diuretic Draft

The Channelers went where no nephrology podcasters have gone before, recording in front of a live audience at the National Kidney Foundation Clinical Meeting in Austin. We had all eight Channelers doing a live podcast. We did a Freely Filtered-inspired draft of the best diuretics. The draft order: Leticia Rolon Anna Gaddy Joel Topf Roger Rodby Josh Waitzman Amy Yau JC Velez And Melanie Hoenig References JC Tolvaptan in Later-Stage Autosomal Dominant Polycystic Kidney Disease Intravenous conivapt...

A Very Special Episode: Meet the Glaucomfleckens

Chapter Eleven, part 1: Regulation of Acid-Base Balance

References We considered the effect of a high protein diet and potential metabolic acidosis on kidney function. This review is of interest by Donald Wesson, a champion for addressing this issue and limiting animal protein: Mechanisms of Metabolic Acidosis-Induced Kidney Injury in Chronic Kidney Disease Hostetter explored the effect of a high protein diet in the remnant kidney model with 1 ¾ nephrectomy. Rats with reduced dietary acid load (by bicarbonate supplementation) had less tubular damage....

Chapter Ten : Acid-Base Physiology

References for Chapter 10 We did not mention many references in our discussion today but our listeners may enjoy some of the references below. Effects of pH on Potassium: New Explanations for Old Observations - PMC although the focus of this article is on potassium, this elegant review by Aronson and Giebisch reviews intracellular shifts as it relates to pH and K+. Josh swooned for Figure 10-1 is this right? Which figure was it? which shows the relationship between [H+] and pH. You can find this...

Chapter Nine: Regulation of Plasma Osmolality

References for Chapter 9 One of the few papers that Rose wrote as a single author explores electrolyte free water clearance. This seminal paper explores the issue in greater detail than the book. A New approach to disturbances in the plasma sodium concentration Wondering about the volume of sweat? Josh taught us that the volume of “transepidermal volume loss” is not affected by humidity https://www.jidonline.org/article/S0022-202X(15)48145-X/pdf but is greatly affected by temperature: Skin tempe...

Chapter Eight: Regulation of The Effective Circulating Volume

References for chapter 8 Robert Schrier proposed a unifying hypothesis to explain the sodium retention seen in edematous states like cirrhosis and heart failure, coining the term effective arterial blood volume (EABV). An open access review in JASN 2007 can be found here: https://jasn.asnjournals.org/content/18/7/2028#ref-3 John P Peters ASN Annual Award: https://www.asn-online.org/about/awards/award.aspx?awh_key=0ea83199-f86d-4506-9507-d7e4ce688cb4 Short article discussing contributions of Dr. ...

Chapter Seven: The Total Body Water and The Plasma Sodium Concentration

Chapter 7 References Sands JM, Blount MA and Klein JD. Regulation of Renal Urea Transport by Vasopressin. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3116377/ In this invited piece, Sands and colleagues explain that although urea is permeable across membranes, this is slow, thus urea transporters in the kidney, under control of vasopressin, are needed to facilitate transport and create the medullary gradient. Text book using 20% of extracellular compartment being in the intravascular compartmen...

Chapter Six part 2: The exciting conclusion to the Effects of Hormones on Renal Function

Chapter 6 part 2. References Josh touts the PARADIGM-HF Trial Angiotensin–Neprilysin Inhibition versus Enalapril in Heart Failure | NEJM which found this combination was superior to an ARB alone Joel mentions an early atrial natriuretic peptide trial by Julie Lewis et al. Atrial natriuretic factor in oliguric acute renal failure - American Journal of Kidney Diseases and here’s a metanalysis that put this option to bed: Atrial Natriuretic Peptide for Management of Acute Kidney Injury: A Systemati...

Chapter Six: Effects of Hormones on Renal Function

Chapter 6 part 1 In this review of vasopressin, you can find an excellent discussion of basic stimuli and vasopressin receptors: Vasopressin V1a and V1b Receptors: From Molecules to Physiological Systems | Physiological Reviews X-Linked Nephrogenic diabetes insipidus is very rare and there was theory that all patients originated from the same family and traveled to the US on the Hopewell ship JCI - X-linked nephrogenic diabetes insipidus mutations in North America and the Hopewell hypothesis. Th...

Chapter Five: Functions of the Distal Nephron

References for Chapter 5--the Distal Nephron Roger pointed out the fact that the distal nephron can achieve very low urinary sodium as evidenced by observations in people from the Yanomamo tribe Blood pressure and electrolyte excretion in the Yanomamo Indians, an isolated population in this report, 84% of the participants had urinary sodium < 1mmol/24 hours. Information about the Yanomamo Tribe. It looks like they’re starting to make chocolate, now! Yanomami The Yanomami are great observers o...

Chapter Four: The Loop of Henle and Counter Current Exchange

Show notes with a full set of references are available here: http://www.rosebook.club/episodes/2021/6/22/chapter-four Also, please fill out our listener survey: https://forms.gle/DVdcJikKZkzY56mXA

Chapter Three: The Proximal Tubule

Chapter Three: How the proximal tubule is like Elizabeth Warren and other truths my friends from Boston taught me

Chapter two part two

The exciting conclusion to Chapter Two: Renal Circulation and Glomerular Filtration Rate

Chapter Two: Renal Circulation and Glomerular Filtration Rate

Back by popular demand…all two of you…the second chapter of The Clinical Physiology of Acid Base and Electrolyte Disorders.

Chapter One: Introduction to Renal Function

The Channel Gang discusses the name of their new podcast and then discuss chapter one of The Book.