Ch. 35 Electrolytes and Acid-Base Status Flashcards
Electrolytes are the ____ of elements found in the body fluids or all organisms
ions
what are positive ions called?
cations
what are negative ions called?
anions
what are the major functions of electrolytes in the body?
maintenance and activation of enzyme systems
acid-base regulation
what does acid-base balance refer to?
the body’s pH balance
What is normal blood pH?
7.35 - 7.45
What is acidosis?
LOW blood pH (<7.3)
What is alkalosis?
HIGH blood pH (>7.4)
When the blood pH falls out of range, the function of the body’s proteins are diminished/destroyed: True or False?
TRUE
What are buffer systems responsible for?
Counteracting acids
What 2 major body systems work to regulate blood pH in the presence of acid-base IMBALANCE?
renal system
respiratory system
Bicarbonate buffer acts when the blood pH is too _______?
acidic
What is the PRIMARY blood buffer system?
The bicarbonate-carbonic acid buffer
Any metabolic condition that results in the build up of acids in the body can result in ______ ________
metabolic acidosis
What is base excess? What does a negative value indicate? a positive value?
the amount of acid or base required for 1L of blood to have a normal pH while the PO2 is held at a constant 40mmHg.
neg value= metabolic acidosis
pos value= metabolic alkalosis
What are the 7 major electrolytes in plasma?
calcium, magnesium, sodium, inorganic phosphorus, potassium, bicarbonate, and chloride
Changes in electrolyte concentrations can result from _________
_________
_________
- incr/decr. intake
- shifts between ICF and ECF
- incr renal retention or incr loss of electrolytes via the kidneys, GI tract, or resp. system
Sodium is the major ____ of plasma and ECF
CATION
What are the main functions of sodium?
water distribution
maintaining body fluid osmotic pressure
Hypernatremia
high blood sodium
Hyponatremia
low blood sodium
what organ is sodium filtered through?
the kidneys
What conditions are associated with high blood sodium levels?
water deprivation, hyperventilation, osmotic diuresis
what conditions are associated with low blood sodium?
GI disorders (V,D)
ketonuria
hypoadrenocorticism (Addison’s)
CHF
Potassium is the major ICF ______?
CATION
What are the major functions of K+ in the body?
- muscular function
- cardiac function
- nerve impulse/transmission
- carbohydrate metabolism
hyperkalemia
high blood potassium
hypokalemia
low blood potassium
Animals with acidosis can have hyperkalemia: true or false?
TRUE
What conditions is hypokalemia associated with?
inadequate K+ intake alkalosis fluid loss 2' to V/D anorexia ketonuria diuresis
What conditions are associated with hyperkalemia?
metabolic acidosis
UO
renal insufficiency
Chloride is the major ECF _____?
ANION
What are the major functions of chloride?
water distribution
osmotic pressure
normal anion/cation ratio
Hyperchloremia
high blood chloride
hypochloremia
low blood chloride
What organ helps regulate bicarbonate levels in the blood?
the kidneys
What is the major function of magnesium?
production/destruction of acetylcholine
hypermagnesemia
high blood magnesium
hypomagnesemia
low blood magnesium
Tetanus can result as an imbalance of magnesium and calcium: true or false?
true
More than 99% of Ca is found in bones, the other 1% functions to ______
- maintain neuromuscular excitability and tone
- maintenance of enzyme activity
- facilitation of blood coagulation
- maintenance of inorganic ion transfer across cell membranes
If the phosphorus falls, the calcium rises and vice versa: true or false?
TRUE
hypercalcemia
high blood calcium
hypocalcemia
low blood calcium
what are the major functions of inorganic phosphorus?
(80% found in bones) other 20%: 1. energy storage, release, and transfer 2. carb metabolism 3. composition of nucleic acids, phospholipids, etc.
The total number of negative charges (anions) = the total number of positive charges (cations) when properly maintained via the buffer systems. When out of balance, this change is termed the _____ _____
anion gap
What is the anion gap primarily used to identify?
metabolic acidosis
What conditions is an increased anion gap assocaited with?
- lactic acidosis
- renal failure
- diabetic ketoacidosis
Where is most CK found in the body?
cardiac muscle, skeletal muscle, and the brain
When skeletal/cardiac muscle is damaged, CK is _______
INCREASED
CK can be used to determine liver disease when AST is high but there is no other signs of liver dz: true or false?
true
Troponin assay evaluates what?
cardiac muscle damage
brain natriuretic peptide (BNP) is a hormone secreted by monocytes that functions to _____?
maintain blood pressure
Increased BNP occurs with ____?
What can it help diagnose?
ventricular filling pressure, can help with dx of heart failure
Increased lactate indicates ______ or _______?
hypoxia or hypoperfusion
Increased lactate levels can also be seen with what condition?
Peritonitis
What are the primary organs of the endocrine system? (4)
the adrenal glands, pituitary gland, and thyroid gland, and parathyroid glands
Adrenal dysfunction is often a result of the misuse of what?
steroids
What is the major hormone released by the adrenal glands?
cortisol
Hyperadrenocorticism is also called what?
Cushing’s disease
Hypoadrenocorticism is also called what?
Addison’s disease
Cushing’s disease is most often caused by what?
overzealous steroid therapy
What is primary hypoadrenocorticism?
adrenal-dependent
What is secondary hypoadrenocorticism?
pituitary-dependent
ACTH and cortisol levels can be used to differentiate between _____ and ______ hypoadrenocorticism?
primary and secondary
Primary hypoadrenocorticism is associated with ____ levels of ACTH, whereas secondary is associated with ____ levels of ACTH
normal to high
low to undetectable
What does the ACTH test evaulate?
the degree of adrenal gland response to the administration of exogenous ACTH
What does the dexamethasone suppression test evaulate?
the adrenal glands response to dexamethasone
What is the difference in usage for the low dose dexamethasone suppression test and the high dose test?
low dose- confirms or replaces the ACTH test for Cushing’s disease
hihg dose- used to differentiate pituitary causes of Cushing’s vs adrenal causes
What does the corticotropin-releasing hormone stimulation test differentiate?
differentiates between pituitary depending Cushings and primary Cushings
What do thyroid hormones affect?
metabolic rate and growth
Thyroxine is composed of what 2 hormones?
thyroxine (T4) and triiodothyronine (T3)
Drugs that may INCREASE t4 concentrations include ….
insulin
estrogens
Drugs that may DECREASE t4 concentrations include…..
glucocorticoids, anticonvulsants, antithyroid drugs, penicillins, trimethoprim sulfamides, diazepam, androgens, sulfonylureas
TSH response test used for borderline thyroid cases: true or false?
true
TSH RESPONSE test usually used for canine hypothyroidism: T or F?
true
Feline hyperthyroidism is usually caused by __________?
functional thyroid adenomas
free T4 is the fraction of thyroxine that is ________?
NOT bound to protein
In cases of GI malabsorption, what is usually indicated to obtain a definitive diagnosis?
intestinal biopsy
GI malassimilation can be classified into 2 categories: ______ and ______
malabsorption
maldigestion
Maldigestion results from _______?
altered gastric secretion, lack of digestive enzymes
malabsorption usually caused by ______?
acquired disease of the small intestine or bacterial overgrowth
fecal occult blood tests what?
occult blood (not seen by naked eye)- r/o GI bleeding
d-Xylose absorption test most often performed on what species?
horses
Serum folate and cobalamin are usually ______ with malabsorptive conditions
DECREASED
What part of the GI tract is folate absorbed?
the proximal intestine
What part of the GI tract is cobalamin absorbed?
the ileum
What is plumbism?
lead poisoning
