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Barry Patho Fluids-B
Barry Patho Fluids-B
33
Medical
02/03/2011

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Term
DESCRIBE BLOOD AS FLUID COMPARTMENT
Definition
Blood contains both ICF (RBC’s) and ECF (plasma) but is considered a separate fluid compartment b/c self contained in circulatory sys.

Blood vol control is extremely important for CV dynamics:
Renal sys
Cardiovascular sys
Avg vol = 8% (5L) of TBW
Term
EXPLAIN CELL MEMBRANE REGARDING FLUID COMPARTMENT
Definition
Acts as boundary b/w ICF & ECF, composed of epithelial & endothelial cells
Term
TOTAL BODY WATER PROPERTIES(TBW)
Definition
Water is 60% of total body mass.
Dependent on:
Age-% dec as get older
Sex- males have higher % b/c of inc muscle mass
Body Type- obese have lower % b/c fat stores less water
Term
HOW IS WATER BALANCE MAINTAINED
Definition
Through a negative feedback mechanism:
Osmoreceptors- connected to hypothalamus (ADH) drive thirst & elimination.
`Inc in osmolarity or dec in vol of extracellular fluid stimulates thirst mechanism.
Term
HOW MUCH WATER FILTERED FROM THE CAPILLARIES
Definition
Every day the body filters 20L of water from the capillaries to the interstitial space. 18L are returned by reabsorbtion and 2L are returned by the lymphatic sys.
Term
PRINCIPLE OF OSMOTIC NEUTRALITY
Definition
Total number of + and - charges within a given compartment must be equal. Particular compartment must be electrically neutral. Does not mean you must have equal numberof pos and neg charges on both sides of the cell membrane. Must have the same number of pos/neg within each particular compartment.Ions kept in compartment so no net charges in a compartment exist.
Term
ECF CATIONS
Definition
Na+ 142 (MOST IMP. ECF CATION)
K+ 5
Ca2+ 5
Mg+ 2
TOTAL 154
Term
ECF ANIONS
Definition
HCO3- 24
Cl- 104
Phos 2
Proteins 16
Others 8
Total 154
Term
CATIONS OF ICF
Definition
ICF (meq/L)
Cations
Na+ 10
K+ 156 (MOST IMP ICF)
Ca2+ 4
Mg+ 26
Total 196
Term
ANIONS OF ICF
Definition
Anions
HCO3- 12
Cl- 4
Phos 40-95
Proteins 54
Others 31-86
Total 196 (avg)
Term
THE 4 TYPES OF PASSIVE TRANS. MECH
Definition
SIMPLE DIFFUSION
FACILITATED DIFFUSION
FILTRATION
OSMOSIS
Term
SIMPLE DIFFUSION
Definition
Simple- no carrier, occurs through membrane openings or intermolecular spaces, always happens in favor of the concentration gradient, based on the kinetic energy of the molecules which causes their movement r/t the concentrations, stops when concentrations are equal
Term
FACILITATED DIFFUSION
Definition
FACILITATED DIFFUSION: IN FAVOR OF CONC. GRADIENT. THERE'S A
MAXIMUM LIMIT DEPENDING ON THE CARRIERS AND THEIR ABILITY TO UNDERGO CONFORMATIONAL CHANGES. Requires carrier protein, there is a max limit based on the carriers & their ability to undergo conformational changes, if carrier unavailable, unable to balance gradient.
Term
FILTRATION
Definition
Filtration- movement of solvent & solute r/t hydrostatic pressure gradient, not concentration. THINK FORCE HYDROSTATIC PRESSURE THROUGH FILTER.
Term
OSMOSIS
Definition
Movement of solvent (water)The movement of water across a selectively permeable membrane from an area of high water potential (low solute concentration) to an area of low water potential (high solute concentration)
Term
TYPES OF ACTIVE TRANSPORT MECH
Definition
1. Active- against concentration gradient, requires carrier (usually lipoprotein that is removed from the substrate by an enzyme once reaches destination) if either energy or carrier unavailable, will not occur. REQ. NA/K PUMP (ATP ENERGY)

2.Bulk (VESICULAR):
Exocytosis- moving out of cell
Endocytosis- moving into cell
Phagocytosis- solid
Pinocytosis- fluid
Term
Osmotic Pressure
Definition
OSMOTIC PRESSURE-exact amt of pressure required to stop osmosis, expressed in # of particles (osmoles), not mass (grams)

Term
Normal Osmolality of ICF & ECF
Definition
300 milliosmol/kg (for solutions use Osmolarity osmol/L)
Term
Tonicity
Definition
Ability of solution to change shape of cell by altering its internal fluid vol, but always be ref to isotonic environment
`Isotonic imbalance- no change, gain or loss of ECF resulting in a concentration = 5% glucose or 0.9% NaCl
`Hypertonic imbalance- cell shrinks, ECF concentration greater than 5% glucose or 0.9% NaCl
`Hypotonic imbalance- cell swells, ECF concentration less than 5% glucose or 0.9% NaCl
Term
Acid
Definition
`A molecule that contains H+ atoms that can be released as H+ in solutions. Ie. HCl & H2CO3 (carbonic acid) “Acidosis”
`Strong Acid- quickly dissociates releasing large amounts of H+ (HCl).
`Weak Acid- less tendency to dissociate & release H+ w/ w/ less enthusiasm (H2CO3)
Term
BASE
Definition
`A molecule that can accept H+ , called alkali b/c usually combo of alkaline metal (Na, K, Li) w/ highly basic ion (OH-). ie. HCO3-, proteins, Hb “Alkalosis”
`Strong Base- react quickly & strongly w/ H+ → quick removal of H+ from the solution by binding them to OH- → water
`Weak Base- binds w/ H+ much weaker than OH-
Term
OSMOLARITY
Definition
`SINCE IT'S NOT PRACTICAL TO MEASURE SOL. IN kg OF H2O (OSMOLALITY) WE DO
IT IN OSMOLES/LITER (OSMOLARITY)
`NORMAL OSMOLALITY OF ECF AND ICF IS 300 MILLIOSMOLES/kg
Term
H ION REGULATION
Definition
`AS WITH OTHER IONS, THE KIDNEYS PLAY A KEY ROLE IN THE REG. OF H+ BUT THIS IS NOT THE ONLY MECHANISM BECAUSE THE LUNGS, BLOOD AND CELLS ARE ALSO INVOLVED.
`PRECISE REG. OF H+ IS ESSENTIAL BECAUSE THE ACTIVITIES OF ALMOST ALL ENZYMES IN THE BODY ARE INFLUENCED BY H+. PROTEIN STRUCTURE DEPENDS ON pH AND EVERYTHING IN THE BODY IS PROTEIN-RELATED.
Term
Hb
Definition
Hb IN THE RBC AND PROTEINS IN THE OTHER CELLS OF THE BODY ARE AMONG THE MOST IMPORTANT BODY'S BASES.
Term
Regulators of H+ to maintain a 20:1 [HCO3-/H2CO3]
Definition
`Kidneys- distal tubules secrete H+ in urine and reabsorb or regenerate HCO3-, ammonia formation, phosphate buffering, most important, slower onset, long-term solution, regulate [H+] by ingestion, production by the body, & excretion
`Lungs- inc RR to dec amount of H2CO3 by blowing off CO2- and leaving water, rapid response to [H+] changes, short-term compensatory mechanism
`Blood/Protein- Hb is an intracellular buffer b/c its ability to bind w/ H+ to form HHb & HHbCO2, protein’s neg charge serves as a buffer b/c of H’s pos charge
`Cells- K+/Na+ enters & H+ exits (alkalosis) or K+/Na+ exits & H+ enters (acidosis) intracellular space
`Bone- exchanges of calcium, phosphate, & release of carbonate
Term
BASES
Definition
`BASES ARE OFTEN CALLED ALKALI
(A MOLECULE FORMED BY A COMBINATION OF ONE OR MORE ALKALINE METALS {Na, K, Li} WITH A HIGHLY BASIC ION LIKE OH{HYDROXIL})
`MOST ACIDS AND BASES RELATED WITH THE NORMAL ACID-BASE
REGULATION IN THE BODY ARE WEAK AND THE MOST IMPORTANT ONES ARE
H2CO3 AND HCO3-.
 
Term
Normal pH values
Definition
1. Arterial- 7.4
2. Venous/Interstitial Fluid- 7.35
3. Intracellular- 6.0-7.4
1. Hypoxia & poor blood flow dec pH
4. Urine- 4.5-8.0
5. Gastric- 0.8
6. Lower limits for life: 6.8-8.0
Term
THREE SYSTEMS THAT WILL ACT AGAINST CHANGES IN THE [H+]:
Definition
1.- BUFFER

2.- KIDNEYS

3.- LUNGS

IF pH BELOW 7.35 = ACIDOSIS
IF pH ABOVE 7.45= ALKALOSIS
Term
RESPIRATORY ACIDOSIS
Definition
Respiratory ACIDOSIS- dec ventilation & inc PCO2 (if no other underlying condition, urine will be acidic via metabolic compensation):
1.Hypoventilation- pathological or pharmaceutical
2.Diffusion imbalance- emphysema, shock, embolism
3.Obstruction- pneumonia, pulmonary edema, cystic fibrosis

(DIFF)=SEE
(OBSTRUCT)=PPC
Term
RESPIRATORY ALKALOSIS
Definition
Respiratory ALKALOSIS- inc ventilation & dec PCO2, usually b/c of hyperventilation by the lungs & rarely from physical or physiological conditions (if no other underlying condition, urine will be basic via metabolic compensation):
1.Psychoneurosis→ Hyperventilation
2.Going to high altitude- hyperventilation to compensate for low [O2]→ inc’d CO2 excretion
Term
METABOLIC ACIDOSIS
Definition
Metabolic ACIDOSIS- not caused by respiratory conditions:
1.Inc amounts of noncarbonic acid in the body:
`Inc H+ load:
a.Renal Failure→ dec excretion of metabolic acids
b.Ketoacidosis/Lactic Acidosis→ formation of excess amts of metabolic acids
c.Inc in metabolic acid via ingestion/infusion of acids (alcohol, ammonium chloride, ethylene glycol, methanol, salicylates, paraldehyde)
`Dec H+ load:
a.Uremia
b.Distal renal tubule acidosis
`Loss of bicarbonate from body:
1.Inability to reabsorb HCO3-
2.Diarrhea
3.Ureterosigmoidoscopy
4.Proximal renal tubule acidosis
Term
METABOLIC ALKALOSIS
Definition
Metabolic ALKALOSIS- results from the inc [HCO3-] in the extracellular fluids b/c of:
1.Excess in retention of HCO3-
2.Inc in excretion of H+ (vomiting)
3.Ingestion of alkaline drugs (NaHCO3, mylanta)
Term
CORRECTION AND COMPENSATION
Definition
THE COMPENSATION MECHANISMS WILL SOLVE OR COMPENSATE THE PROBLEM IN A TEMPORARY WAY WITHOUT SOLVING ITS CAUSE, WHILE THE CORRECTION ONES WILL SOLVE THE PROBLEM IN A PERMANENT WAY BY
CORRECTING ITS CAUSE.