Rishi Desai, MD, MPH

Yifan Xiao, MD

Free water clearance

Wikipedia

Figure 63.8 ADH is produced in the paraventricular and supraoptic nuclei in the hypothalamus, stored in Herring bodies in paraventricular and supraoptic neurons, and released into the bloodstream from the posterior pituitary gland.  FREE WATER CLEARANCE osms.it/free-water-clearance ▪ Free water: water without solutes ▪ Free water clearance: rate at which kidneys ﬁlter free water out of blood plasma  PATHWAY  ▪ Free water ﬁltered out of blood plasma in ascending limbs, distal convoluted tubules of kidneys’ nephrons, solutes removed ▪ Free water reabsorbed into circulation through aquaporin protein channels in collecting ducts  554 OSMOSIS.ORG  ANTIDIURETIC HORMONE EFFECTS  ▪ High amounts of ADH → lots of free water reabsorbed, retained (negative free water clearance) → hyperosmotic urine ▪ Low amounts of ADH → little free water reabsorbed, excreted (positive free water clearance) → hypoosmotic urine ▪ Free water clearance, 0: excreted urine has same osmolarity as blood plasma ▪ CH2O = V - (Uosm/Posm)V ▫ V: urine ﬂow rate (mL/min) ▫ Uosm: urine osmolarity ▫ Posm: plasma osmolarity   

Anatomy of the abdominal viscera: Kidneys, ureters and suprarenal glands

Anatomy clinical correlates: Other abdominal organs

Abdomen

Anatomy of the urinary organs of the pelvis

Anatomy of the female urogenital triangle

Anatomy of the perineum

Anatomy of the male urogenital triangle

Anatomy clinical correlates: Male pelvis and perineum

Anatomy clinical correlates: Female pelvis and perineum

Pelvis and perineum

Anatomy

Development of the renal system

Embryology

Ureter, bladder and urethra histology

Kidney histology

Histology

Renal system anatomy and physiology

Anatomy and physiology

Hydration

Body fluid compartments

Movement of water between body compartments

Fluid compartments and homeostasis

Renal clearance

Glomerular filtration

TF/Px ratio and TF/Pinulin

Measuring renal plasma flow and renal blood flow

Regulation of renal blood flow

Renal clearance, glomerular filtration and renal blood flow

Tubular reabsorption and secretion

Tubular secretion of PAH

Tubular reabsorption of glucose

Urea recycling

Tubular reabsorption and secretion of weak acids and bases

Renal tubular reabsorption and secretion

Proximal convoluted tubule

Loop of Henle

Distal convoluted tubule

Renal tubular physiology

Renin-angiotensin-aldosterone system

Sodium homeostasis

Potassium homeostasis

Phosphate, calcium and magnesium homeostasis

Renal electrolyte regulation

Osmoregulation

Antidiuretic hormone

Kidney countercurrent multiplication

Renal sodium and water regulation

Vitamin D

Erythropoietin

Renal endocrine functions

Physiologic pH and buffers

Buffering and Henderson-Hasselbalch equation

The role of the kidney in acid-base balance

Acid-base map and compensatory mechanisms

Respiratory acidosis

Metabolic acidosis

Plasma anion gap

Respiratory alkalosis

Metabolic alkalosis

Acid-base physiology

Physiology

Renal agenesis

Horseshoe kidney

Potter sequence

Hyperphosphatemia

Hypophosphatemia

Hypernatremia

Hyponatremia

Hypermagnesemia

Hypomagnesemia

Hyperkalemia

Hypokalemia

Hypercalcemia

Hypocalcemia

Renal tubular acidosis

Minimal change disease

Diabetic nephropathy

Focal segmental glomerulosclerosis (NORD)

Amyloidosis

Membranous nephropathy

Lupus nephritis

Membranoproliferative glomerulonephritis

Poststreptococcal glomerulonephritis

Goodpasture syndrome

Rapidly progressive glomerulonephritis

IgA nephropathy (NORD)

Alport syndrome

Kidney stones

Hydronephrosis

Acute pyelonephritis

Chronic pyelonephritis

Prerenal azotemia

Renal azotemia

Acute tubular necrosis

Postrenal azotemia

Renal papillary necrosis

Renal cortical necrosis

Chronic kidney disease

Polycystic kidney disease

Multicystic dysplastic kidney

Medullary cystic kidney disease

Medullary sponge kidney

Renal artery stenosis

Renal cell carcinoma

Angiomyolipoma

Nephroblastoma (Wilms tumor)

WAGR syndrome

Beckwith-Wiedemann syndrome

Renal and ureteral disorders

Posterior urethral valves

Hypospadias and epispadias

Vesicoureteral reflux

Bladder exstrophy

Urinary incontinence

Neurogenic bladder

Lower urinary tract infection

Transitional cell carcinoma

Non-urothelial bladder cancers

Bladder and urethral disorders

Congenital renal disorders: Pathology review

Renal tubular defects: Pathology review

Renal tubular acidosis: Pathology review

Acid-base disturbances: Pathology review

Electrolyte disturbances: Pathology review

Renal failure: Pathology review

Nephrotic syndromes: Pathology review

Nephritic syndromes: Pathology review

Urinary incontinence: Pathology review

Urinary tract infections: Pathology review

Kidney stones: Pathology review

Renal and urinary tract masses: Pathology review

Renal system pathology review

Pathology

Osmotic diuretics

Carbonic anhydrase inhibitors

Loop diuretics

Thiazide and thiazide-like diuretics

Potassium sparing diuretics

Diuretics

ACE inhibitors, ARBs and direct renin inhibitors

Chronic kidney disease medications

Pharmacology

Medical Physiology

Human Anatomy & Physiology

Principles of Anatomy and Physiology

PubMed

The development of the clearance concept

The current place of urea kinetic modelling with respect to different dialysis modalities

Free water clearance

Videos

Notes