Term
Intracellular Fluid
Extracellular Fluid |
|
Definition
fluid within cells. potassium, protein, phosphate, sulfate
fluid outside cells - interstitial fluid and plasma sodium and chloride
Cell membrane is the barrier to movement. O2 and CO2 diffuse but the ions must be pumped. Water crosses by osmosis which is driven by the number of particles |
|
|
Term
Dissociation
Electrolytes dissociate into ions in solution
NaCL --> Na+ + Cl-
Cations = Anions |
|
Definition
|
|
Term
DEFINITIONS
Diffusion - movement of particles down a gradient
Osmosis - movement of water across membrane in response to solute. Water moves toward the side with the greatest number of solute particles
Tonicity = the impact of the osmotic pressue on a cell
Isotonic - conc of particles in solution = conc of particles in rbc
Hypotonic - distilled h10 add rbc h20 would move into rbc (toward high conc of particles causing the particle to sweel
Hypertonic - Cells shrink in hypertonic solutions - h20 moves out of the cell.
Difference in height between the two is osmotic pressure. |
|
Definition
|
|
Term
Total body water = 60%
Intracellular is 2/3 of this
Interstitial is 2/3 of extracellular fluid the rest is transcellular fluid, csf, peritoneal fluid, pleural fluid, etc. 5% is plasma |
|
Definition
|
|
Term
Capillary Interstitial Exchange - 4 main fources that control the movement of water between the capillary and interstitial spaces
1. The capillary filtration pressure which PUSHES water out of the capillary into the interstitial fluid
2. The capillary colloidal osmotic pressure which PULLS water back into the capillary
3. The interstitial or tissue hydrostatic pressure which OPPOSES the movement of water out of the capillary
4. The interstitial colloidal osmotic pressure which PULLS water out of the capillary into the interstitial spaces.
Outward Pressure |
|
Definition
|
|
Term
| 1. Capillary Filtration/hydrostatic pressure - outward forces |
|
Definition
Pushes water out of capillary and into interstitial though a mechanical (not osmotic) force
- also higher at the arterial end then the venous end
- aka capillary hydrostatic pressure |
|
|
Term
| 2. Capillary Colloidal Osmotic Pressure - Inward Pressure |
|
Definition
| - pressure generated by the plasma proteins that are too large to pass through the pores of the capillary wall. It pulls fluids back into the capillary. |
|
|
Term
|
Definition
a swelling produced by an increase in interstitial fluid volume. Not evident until it is increased by 2.5 to 3.5 L
Causes:
1. Increased capillary filtration (hydrostatic pressure - More fluid leaves the capillary space.)
- Usually from an increased venous pressure
- Can be from increased pressure at the arterial end of the capillary
- Increased vascular volume (venous pressure) - heart failure, kidney disease, premenstrual sodium retention, pregnancy, environmental heat stress, thiazolidinedione therapy
- Venous obstruction - liver disease with portal vein pbstruction, acute pulmonary edema, venous thrombosis
- Decreased arteriolar resistance, calcium channel blocking drug responses
2. Decrease the capillary colloidal osmotic pressure
- less fluid in the capillary
- usually from low albumin
- Increased loss of plasma proteins - protein loss kidney disease, extensive burns
- Decreased production of plasma proteins - liver disease, starvation, malnutrition
3. Increase capillary permeability
- plasma leaks out of capillaries
- Inflammation, allergic reactions, malignancy, tissue injury and burns
4. Produce obstruction to lymph flow
- prevents return of proteins and fluids to circulation
- Malignant obstruction of lymphatic sutures, surgical removal of lymph nodes
Manifestations - determined by location - feet vs lung vs brain
Assessment/treatment - weight, visual, measurement of affected part, elevate lower extremities, support stockings and diuretics
Can get edema around the cavities - pleural, pericardial, peritoneal - may require damage |
|
|
Term
|
Definition
| The lymphatic system accessory system by which fluid can be returned to the circulatory system. Normally the forces moving fluid out of the capillary into the interstitial are greater than those returning fluid to the capillary. Any excess fluid that may leak into the interstitium are picked up by the vessels of the lymphatic system and returned to circulation. |
|
|
Term
Sodium & Water Balance
REgulation |
|
Definition
regulation of water balance - 60% of total body weight in adults and 75% in infants. Intake is drink, food, metabolism
regulation of sodium balance - most plentiful outside the cell. Intake from the gI - output is renal, skin, and urine |
|
|
Term
| Sodium and Water Regulation - Homeostasis Disturbed by an increase in the ECF by fluid gain or fluid and Na+ gain (sodium) |
|
Definition
1. Increase in blood volume and arterial distention
2. Increase in Naturetic Peptide release (hormone)
3. Results in three things
- decrease in aldosterone release which results in increased urinary sodium loss
- decrease in ADH antidiuretic hormone which increases urinary water loss and also decreases thirst and decreses water intake |
|
|
Term
| Sodium and Water REgulation - Homeostasis disturbed by a decrease in the ECF by fluid loss or Na+ loss |
|
Definition
Decrease in blood volume and blood pressure
- increased renin secretion and angiotensin II activiation causes two effects
1. Increased aldosterone release which increses urinary sodium retintion
2. Increased ADH antidiuretic hormone which results in a decreased urinary water loss. Also an increased thirst and increased water intake |
|
|
Term
|
Definition
Hypothalmus controls thirst - which contains osmoreceptors
Stimulationby low ECF or cellular dehydration. Renin aldosterone system also stimulates thirst.
- Hypodipsia - decreased ability to sense thirst. Can be caused by lesions of the hypothalmus
- Polydipsia - excessive thirst.
a. True thirst - accompanies dehydration.
b. Inappropriate thirst from Chronic Renal Failure or Heart Failure from high angiotensin.
c. Psychogenic polydipsia compulsive drinking in psychiatric disorders
ADH disorders (Antidiuretic hormones)
1. Diabetes Insipidus - decrease in adh or response with an increase in urinary output and dehydration
Neurogenic DI - trauma results in a Rx wtih adh admin
Nephrogenic DI = renal response of ADH decreased
2. SIADH - syndrome of Inappropriate Diuretic Hormone
- too much ADH results in a decrease of urinary output and water retenition . ADH secretion by a tumor causes of dilutonal hyponatremia , Rx is diuretics and fluid restriction |
|
|
Term
| Disorders of Water and Sodium Balance - Isotonic |
|
Definition
3. Isotonic Fluid Volume Deficit - loss of fluid from the ECF. Causes: include vomiting, diarrhea, NG suction
Manifestations: thirst, weight loss, oliguria (not enough urine),
RX: correct prob and replace loss with isotonic fluid -
Note: ICF is not effected by this
4. Isotonic fluid volume excess - gain of isotinc fluid in ECF
Causes: renal or heart failure, cortisol excess,
Manifestations: weight gain, edema, distended neck veins, pulmonary edema, ascites
RX: sodium restriction and diuretics
Note: ICF not impacted |
|
|
Term
| Disorders of Water and Sodium Balance - non isotonic balance |
|
Definition
1. Hyponatremia - low Na+ serum <135 and low serum osmolality
Loss of sodium in excess with or even without water loss
Gain of water without sodium
Causes: SIADH renal disease which results in water retention.
Manifestations: neuro symptoms like a headache and disorientation muscle cramps weakness
Rx: limit water intake, giver hypertonic sodium solutions if severe
2. Hypernatremia serum Na+ <145 and serum osmolaity is > 295
Results from gain of sodium or loss of water
Causes: lack of water access, hypodypsia, excess sodium bicarbonate
Manifests: as weight loss polycythemia (invcrease in RBC or a decrease of plasma but either way there is an increase), thirst, neur symptoms
RX: Give rehydration fluids, slowly to avoid cerebral edema |
|
|
Term
| Potassium Balance Regulation |
|
Definition
Normal Serum Volume
Renal Regulation - potassium filtered nad partially reapbsorbed, excretion is fine tuned by aldosterone sesnitive sodium reabsorption/potassium secretion in DCT (distal and cortical collecting tubules)
ECF/ICF shifts - sodium and potassium pump
Cellular dehydration --> increase potassium shift out of cells
Intercellular acidosis --> increase potassium shift out of cells. If
you have a patient in ketoacidosis you give them potassium because if you don't now they are going to be low in the serum soon (no way to measure within the cells)
Insulin and Epi stimulate pump - increse in potassium movement back into the cells such as after a meal. |
|
|
Term
|
Definition
Disorders of the potassium bvalance
Resting membrane potential determined by ECF/ICF and K+
Hyperkalemia reduces the ration
Hypokalemia increase the ration
Hypookalemia K+ <3.5 mEqL
Causes: by decrease intake, GI loss from vomiting or diarrhea, renal loss diuretics, shfits into cells such as epi and insulin as seen during the treatment of ketoacidosis.
Manifests: PR prolonged T wave flatttened, PVC (?) weakness fatigue muscle cramp
RX: Replace IV if rapid replacement needed
Hyperkaliemia - K+ > 5.0
Causes: decrease in renal elimination (such as CRF), increase movement from ECF (acidosis)
Mainfestations: peaked T wave, short QT, wide QRS weakness and muscle cramps
Rx: CaCl2 to reverse ECG changes, beta-agonists, insulin |
|
|
Term
|
Definition
Regulation of Calcium -
Parathyroid hormone increases calcium absorption for gut (via Vit D), decrease in renal elimination, stimulates osteoclasts
Calcitonin results in a decrease of calcium which increases renal elimination, stimulates osteoblasts |
|
|
Term
|
Definition
Hypoparathyroidism - PTH deficit is a decrease of Calcium
From: Congenital absence of the gland, acquired surgical removal or irradiation
Manifests as tetany, prolonged QT
RX: Iv calcium gluconate, Vit D
Hyperparathyroidism - Excess PTH results in an Increase in Calcium levlels
From parathyroid adenoma
Skelteal abnormalities may be asymptomatic |
|
|
Term
| Disorders of Calcium Balance |
|
Definition
Most of the body's calcium is in the bone.. In ECF 1/2 the calcium bound to albumin and 1/2 free
Hypocalcemia - total serum ca++ <8.5
Causes: Renal Loss and Hypoparathyroidism
Manifestations: Nerve and Muscle Excitability
Ca++ stabilizes membranes --> tingling spasms and seizures
Chvostek sign - contracture of facial muscls from light tap
Trosseau sign - carpal spasms from inflating BP cuff
RX: replace calcium
Hypercalcemia - total serum calcium > 10.5
Causes: bone resorbtion (cancer) and hyperparathyoidism
Manifestations: decreased neural excitability |
|
|
Term
| Disorders of Magnesium Balance |
|
Definition
Hypomagnesia < 1.8
causes: diarrhea, malabsorbtion, laxative abuse
Manifestations: tachycardia and hypertension
Hypermagnesia > 11.6
Causes: renal disease, + magnesium containg meds
Manifestations: hypotension, cardia arrest (bradycardia) |
|
|
Term
|
Definition
| Reabsorbtion in distal and cortical tubes stimulated by the PTH |
|
|
Term
| 3 levels of Ph and regulation in the blood |
|
Definition
pH is important because many enzymes are sensitive to ot and cardiac and neural function is decreased when Ph is decreased.
regulation
1. Buffer system
a. Bicarbonate buffer system - adds hydrogen ions to the system
b. Protein buffer system - proteins can funcation as acidsa nd bases so more useful. Albumin and globulins are major plasma proteins
c. Potassium hydrgoen ion exchange
In acidosis it increases hydrogen in the ceela nd potassium leaves the cells (treatment of ketoacidosis often requires potassium replacement)
2. Respiratory control of CO2 - an increased production of meatbolic acids or CO2 stimulates chemoreceptors. decreases CO2 to more normal PH
3. Renal Control Kidney changes it's exretion of acid or base to compensate for Ph changes. |
|
|
Term
| Carbon Dioxide produced in cells and diffused in plasma arried in 3 forms |
|
Definition
70% transported as bicarbonate dissolved in plasma
10% co2 dissolved dissolved in plasma
20% transported as co2 bound to hemoglobin |
|
|
Term
| Ph test acidosis and alkalosis |
|
Definition
Lab tests tell Ph
abnormal Co2 shows problem is respiratory
abnormal bicarbonate - prob is metabolic
- respiratory system can adjust c02 to compensate for a metabolic disorder
- renal system can adjust bicarbonate to compensate for respiratory disorder
- mix acidosis or alkalosis is also possible |
|
|
Term
|
Definition
represents the other stuff in the anions - phosphate, sulfate, organic acids, protein.
increased in lactic acid and ketoacidosis - when large amounts fo lacatate and ketones are present. Normal in metabolic acidosis from diarrhea - chloride is retained as bicarbonate is lost. It helps to confirm diagnosis. |
|
|
Term
|
Definition
Ph is low
Decreased Bicarbonate
Increased minute ventilation may cause a decrease in CO2 to compensate
Causes - production of metabolic acids (keto, lactic acidosis) which will result in an increased anion gap. Diarrhea, acid ingestion, poisoning with ethylene glycol or methanol, kidney disease
Manifesta as Kussmaul breathing, weakness and fatigue, decreased cardiac function at a ph ~ 7.1
Rx correct cause. Sodium bicarbonate may be useful |
|
|
Term
|
Definition
Ph is increased
Increased bicarbonate is the cause
Decreased minute ventilation may cause an increase in CO2 to compensate
Cause excessive intake of anatacids
Loss of hydrogen ions from things like vomiting NG suction or binge/purge
ECF loss
Manifestations - hypoventilation, excitability, may be asymptomatic
Treatment - correct underlying problem, correct fluid and electrolyte abnormalities |
|
|
Term
|
Definition
Ph is decreased
Increased Co 2 is the cause
Bicarb will increase to compensate
Causes = decreased minute volume as chronic in COPD, acute in nartotic OD and neuromuscular disease
Increase in CO2 production from things like fever, sepsis, burns
Symptoms - depends on cause. May have hypoxia, menurological symptoms - headache, blurred vision, eventually coma
Treatment is to improve ventilation |
|
|
Term
|
Definition
Increase in Ph
Decreased CO2 is teh cause
Bicarbonate will decrease to compensate
Causes increased inute volume, central or peripheral stimulation, mechanical ventilation, anxiety or pain
Symptoms: decreased brain blood flow which will result in diziness, Increased pH results in an increase in calcium binding to protein
Treatment - correct the cause (hypoxia) rebreathing for anxiety |
|
|
Term
|
Definition
low potassium levels
low fluid level |
|
|
Term
|
Definition
high potassium levels
low fluid level |
|
|
Term
|
Definition
high blood sodium
low fluid |
|
|
Term
|
Definition
decreased blood sodium
decreased fluid
cause - diarrhea, heart failure, pancreatitis, burn, diarrhea |
|
|
Term
|
Definition
| Diabetic ketoacidosis, in which a person with diabetes cannot use sugar as energy source and resorts to the use of fats to satisfy its energy requirements, can also result in low potassium levels, or can cause hyperkalemia, abnormally high level of potassium. |
|
|
Term
|
Definition
| The single most important effect of antidiuretic hormone is to conserve body water by reducing the loss of water in urine. A diuretic is an agent that increases the rate of urine formation. Injection of small amounts of antidiuretic hormone into a person or animal results in antidiuresis or decreased formation of urine, and the hormone was named for this effect. |
|
|
Term
|
Definition
e. No change in compensatory variable it’s an uncompensated disorder
f. Change in compensatory variable but Ph still normal it’s a partially compensated
g. Change in compensatory variable but Ph normal it’s fully compensated. |
|
|
