Chapter 26 (Lecture) Flashcards
if the cause of the imbalance is respiratory, often what will try to compensate
kidneys
if the cause of imbalance is metabolic, what will try to compensate
respiratory system
- breathing is imparied so PCO2 levels are high and blood pH is low
- if the kidneys are trying to compensate, HCO3- levels will also elevate
respiratory alkalosis
- breathing rate is increased - PCO2 levels will be lower and pH will be higher
- if the kidneys are trying to compensate HCO3- levels will begin to fall
respiratory alkalosis
- the is a renal problem-blood pH is lower and blood HCO3- levels are lowered
- respiratory systems compensates by increasing the increasing the rate and depth of breathing–so PCO2 levels go down below normal
metabolic acidosis
- there is a renal problem–blood pH is higher and blood HCO3- levels are elevated
- respiratory systems compensates by decreasing the rate and depth of breathing–so PCO2 levels go up and pH levels go down
metabolic alkalosis
- caused by any condition that impairs gas exchange, also shallow breathing can cause it
- most common cause of acidosis
- PCO2 increases and pH decreases
respiratory acidosis
- hyperventilation, tumor affecting respiratory center
- CO2 is washed out of the body too quickly
- PCO2 decreases and pH increases
respiratory alkalosis
- severe diarrhea, renal failure, starvation, excessive alcohol intake
- low blood pH and low blood HCO3- levels
- not caused by CO2 fluctuations
metabolic acidosis
- vomiting or suctioning of acidic gastric contents, excessive bicarbonate intake
- increasing blood pH and increasing HCO3- levels
metabolic alkalosis
normal pH range of plasma
7.35-7.45
normal range of PCO2 in plasma
35-45 mmHg
normal range of HCO3- in plasma
22-26 mEq/L
- the ultimate acid-base regulatory system
- slowest action, but it is the only system that can get rid of acids generated by metabolism (phosphoric, lactic, ketoic acids)
- kidneys can also conserve and generate new bicarbonate ions as needed
renal regulation
increased H+ leads to increased CO2 levels and to
increased respiration
buffer types
- physiological (respiratory and renal)
- chemical
- 1-2 times stronger than chemical buffers
- acts more slowly than chemical buffers
- works with CO2 levels
- increased H+ leads to increased CO2 levels and to increased respiration
respiratory regulation
- intracellular proteins are the most powerful ICF buffers in the body
- can bind or release H+ when necessary
protein buffer system
- does the same as a bicarbonate buffer, but works more in the nephron than in the plasma
- has a more powerful effect on the ICF and nephron
phosphate buffer system
NaH2PO4
- converts strong acids and bases into weak acids and bases
- primary buffer in the ECF
bicarbonate buffer system
H2CO3
- one or two molecule systems that resist changes in pH
- bind H+ if pH drops
- release H+ is pH rises
chemical buffers
types of chemical buffers
- bicarbonate
- phosphate
- protein
dissociate completely in solution and greatly affect pH
strong acids
ex: HCl
partially dissociate and act as buffers
weak acids
ex: H2CO3
whenever pH drops below 7.35
acidosis
fluid inside of cells, makes up about 40% or 25L of body weight
intracellular compartment
whenever pH rises above 7.45
alkalosis
decreased calcium ions in plasma
hypocalcemia
causes of hypocalcemia
nutritional, vitamin D deficiencies, burns
symptoms of hypocalcemia
- neuromuscular excitability
- tetany
- depressed excitability of the heart
increased calcium ions in the plasma
hypercalcemia
causes of hypercalcemia
hyperparathyroidism, too much vitamin D
symptoms of hypercalcemia
- bone wasting
- fractures
- kidney stones
- cardiac arrhythmias
- depressed respiration
total body water =
40L or roughly 60% of total body weight
all fluid outside of cells, makes about 20% or 15L of body
extracellular compartment
subcompartments within the extracellular fluid
- interstitial fluid
- plasma
- lymph
- CSF
- synovial fluid
- different than extracellular composition due to the presence of selectively permeable cell membrane
- most proteins, larger molecules remain in the intracellular fluid
- water moves in and out via osmosis
intracellular compartment composition
- fluid and electrolyte intake must equal output by kidneys, liver, and lungs
- substances such as RBC, albumins stay in the blood vessels
extracellular compartment composition
water intake should = ……. each day
water ouput
average daily water intake/output should equal
2500ml/day
water is obtained through
- 60% drinking
- 30% moist food
- 10% internal metabolic pathways
water is lost through
- urine = 60%
- feces = 4%
- sweat = 8%
- skin diffusion and lung evaporation (heat) = 28%
calcium levels are regulated by which hormone majorly
parathyroid hormone
smaller extent calcitonin
decreased blood calcium =
increased PTH secretion; raises blood calcium
PTH targets
bone, kidneys, GI tract
increased blood calcium =
decreased calcitonin; lowers blood Ca