body fluids/kidneys Flashcards
What are the ions in intracellular and extracellular compartments?
Intracellular: potassium and phosphate ions
-protiens, magnesium and sulfate
Extracellular: chlorine, sodiums, bicarbonate, Calcium and less protein inside the cell.
What’s the difference between osmolarity and osmolality?
What makes an effective osmole?
What are some osmoles found in plasma?
Osmolarity is milliosmoles/liter of solution while osmolality is milliosmoles/kg of solvent
A solute that does not easily cross a membrane is an effective osmole because it creates an osmotic force for the movement of water.
- phospholipids
- cholesterol
- neutral fat
- glucose
- urea
- uric acid
- creative
- bilirubin
- bile salts
In what ways are fluids taken in and loss in the system?
What is a general relationship that can be drawn about fluid intake and fluid loss?
Fluid intake: -ingestion: fluid or food -metabolism Fluid loss -insensible evaporation (more extreme with severe burns) -sweat -feces -urine
Fluid intake is or should be equal to fluid loss.
What make up the Basic Metabolic Profile (BMP)??
What are the normal values?
Compliation of solutes found in extracellular fluid, from interstitial, plasma and trancellular. BMP is what a doctor looks at in a basic blood sample
[Na+] - 140 mEq/L [Cl-] - 104 mEq/L [K+] - 4 mEq/L [HCO3-] -24mEq/L BUN - 15 mg/dl Cr - 1 mg/dl Glucose - 80 mg/dl
What’s the osmolarity gap? How is it calculated and what widens the gap?
Osmolarity gap: difference between the measured osmolality and the estimated osmolality.
Calculated from percent compositions of Na+, glucose and urea.
These are commonly encountered things that elevate the osmolar gap:
- ethanol
- methanol
- ethylene glycol
- acetone
- mannitol
Osmotic Pressure
19.3 mmHg of osmotic pressure across a cell membrane for each mOsm concentration gradient of an impermeant solute.
Osmolality = osmoles/kg water Osmolarity = osmoles/liter of solution
Example of calculating osmotic pressure:
0.9% soln off NaCl (mwt = 58.5 g/mol)
(9 g/L) / (58.5 g/mol) * 2 = 0.308 osm/L
Osmolarity = 308 mOsm/L
Potential osmotic pressure = 308 mOsm/L x 19.3 mmHg/mOsm/L
= 5944 mmHg
What will happen to a cell that an isotonic solution is added to it?
Nothing will happen, the concentration of water on the outside and inside of the cell will not change, water can move but theres no real change and the cell with neither burst or crenate.
Isotonic solutions: 282 mOsm/L
- 0.9% NaCl
- 5% Glucose
What happens to a cell when entered into a hypertonic solution?
Intracellular volume decreases
Extracellular volume increases
Osmolarity increase in both compartments
Water drove OUT of the cell to compensate for the high concentration of solute on the extracellular space.
> 282 mOsm/L
What will happen to a cell entered in a hypotonic solution?
Volume in both compartment increase while the osmolarity decreases in both
Water flows into the cell because there’s higher concentration of solute on the intracellular side than the extracellular side.
< 282 mOsm/L
What are the causes and consequences of hyponatremia?
Loss of NaCl or gain of fluids.
Vomiting and diarrahea can lead to loss of NaCl.
Addison’s disease caused a decrease in the secretion of
Aldostrone and the kidneys fail to reabsorbed sodium.
Excess of ADH can cause water to be reabsorbed and lead to overhydration and hyponatremia.
Hyponatremia can cause brain cell edema, and swellling of the brain. This can cause the brain to herniated and permanent brain damage. Other tissue swell as they pump electrolytes out to the extracellular fluid. Correctly/treating this problem to quickly can cause osmotic injury and demyelination.
What are the causes of Hypernatremia?
Water loss and excess sodium cause hypernatremia
Inability to secrete antiduiretic hormone -> kidney to excrete large amounts of water
-> Central Diabetus insipidus
Excess sodium in the extracellular fluid can lead to overhydration, the body responds with by an increased secretion of aldostrone which retains water.
What are three conditions that are prone to causing intracellular edema?
- Hypernatruremia
- Depression of the metabolic systems of tissues
- Lack of adequate nutrition to the cells
What’s the difference between intracellular and extracellular edema?
Intracellular edema can be caused by a decrease in blood flow which causes decreased function of ionic pumps and ions leak into the cell causing water to follow. -> edema
Death of tissue
Extracellular edema has two major causes: failure of the lymphatic system to pick up interstitial fluid or increase capillary filtration. Leading to too much fluid in the extracellular spaces.
How is the kidney anatomically organized?
Covered with a capsule
Followed by a renal cortex made of Bowmen’s capsules and proximal and distal convoluted tubules
The renal medulla has renal pyramids and the renal pelvis with the major and minor calyces.
What’s the structure of Nephron
A Bowman’s tubule with a proximal tubule leading to the loop of Henle and back to the distal tubule back to the collecting tube.
There’s cortical nephrons with glomeruli in the outer Cortex and short loops of henle
Then juxtamedullary nephrons with glomeruli deep in the renal cortex with long loops of henle. Have long efferentarterioles with peritubular capillaries
How does blood flow in and out of the kidney?
Into the renal artery,
through interlobar arteries and
breaking into accurate arteries and into interlobular arteries,
finally afferent arterioles
lead to glomerular capillaries and efferent arterioles.
Peritubular capillaries lead out into interlobular veins,
out arcuate veins and interlobar veins
and out of the kidney in renal veins.
What is the micturition reflex? And the steps?
Micrurition contractions begins as the bladder fills
Sensory signals from stretch receptors: from sacral region of spinal Conrad via pelvic nerves, and flexively back to the bladder through parasympathetic nerves.
Happen spontaneously after bladder is partially filled, and is self-regenerative but disapates after a few seconds.
As the bladder fills more the contractions get stronger and happen more often. When strong enough a second reflex occurs
Pudendall nerves inhibit external sphincter
-> higher brain centers in the pons keep this partially inhibited until time to peee.
Cortical centers and the sacral micturition centers initiate the felled and inhibit the external urinary sphincter.
