exam 2: acid-base Flashcards
What happens when there is an acid-base balance?
changes in H+ concentration
How do you measure acid-base balance?
in blood via pH
what happens when blood is acidic?
increase in H+ concentration
increase in CO2
decrease in HCO3-
ph < 7.35
What are clinical manifestations of acidosis?
CNS:
lethargy, confusion, CNS depression leading to coma
RESP:
deep, rapid kussmaul respiration
what happens when blood is alkaline?
decrease in H+ concentration
decrease in CO2
increase in HCO3-
pH > 7.45
what are clinical manifestations of alkaline?
CNS:
nervousness, hyperactive reflexes, convulsions
RESP:
slow, shallow respirations
cardiac dysrhythmias
How does the lungs help with regulating blood pH
by rapidly exhaling CO2
how does the kidneys help with regulating blood pH
promotes reabsorption of HCO3- by expelling reserves when body is too acidic
normal lab values for pH
7.35-7.45
normal lab values for PaCO2
35-45
normal lab values for HCO3-
21-28
normal lab values for PaO2
80-100
normal lab values for SaO2
95-100%
What is allen test?
to check for adequate arterial perfusion by drawing arterial blood
what are volatile body acids
can be eliminated as CO2 gas or H2CO3
what are nonvolatile body acids
can only be eliminated by the kidneys
- lactic, sulfuric, phosphoric
what happens when someone is in metabolic acidosis
low pH
normal or low HCO3-
what causes metabolic acidosis?
DKA, starvation, lactic acidosis-shock, hypoxemia,
severe diarrhea, renal failure
what are symptoms of metabolic acidosis?
headache, lethargy, kussmaul respirations, n/v, confusion, coma
what happens when someone is in metabolic alkalosis
high pH
high HCO3-
what causes metabolic alkalosis?
vomiting, gastric suction (HCl- loss)
diuretics (K/NA loss)
antacids
hyperaldosteronism
what are symptoms of metabolic alkalosis?
weakness, muscle cramps, hyperactive reflexes, tetany, confusion, slow and shallow respirations, nausea, seizures
what happens when someone is in respiratory acidosis?
low pH
high PaCO2
what causes respiratory acidosis?
hypoventilation (no adequate perfusion), respiratory depression (narcotics, head injury), respiratory muscle weakness, asthma, COPD, pneumonia, pulmonary edema, drowing
what are the symptoms of respiratory acidosis
bradycardia, hypotension, agitation, confusion, combativeness
what happens when someone is in respiratory alkalosis
high pH
low PaCO2
what causes respiratory alkalosis?
hyperventilation, hypermetabolic states, anxiety, fever, pain, pneumothorax
what are symptoms of respiratory alkalosis?
tachycardia, anxiety, confusion, diaphoresis, dizziness, coma
how does the body maintain normal pH through respiratory acid-base control
lungs during exhalation
how does the body maintain normal pH through renal acid-base control
exchange of H+ for Na+ in tubules (excrete in urine)
what is a buffer
chemical that can bind excessive H+ or OH- without a significant change in pH
what are the two primary buffers of the body
HCO3- and phosphate ions
what is a bicarbonate-carbonic acid buffering
- recycles bicarbonate by reabsorbing in kidney if there is good reserve
- create new bicarbonate if need more than reserve by using CO2 + H2) releasing the new bicarbonate into plasma to neutralize pH
what is a protein buffering
intracellular/plasma
- has negative charges and serves as a buffer for H+
-renal buffering (kidney): phosphate buffer and ammonia buffer (renal tubules)
what happens when gas is being transported?
delivery of O2 to the cells of the body
removal of CO2
what are the steps in O2 gas transportation
-ventilation of lungs
-diffusion of O2 from alveoli into capillary blood
-perfusion of systemic capillaries with oxygenated blood
-diffusion of O2 from systemic capillaries into the cells
what are the steps in transporting CO2 gas?
(reverse)
-diffusion of CO2 from cells into capillaries
-perfusion of pulmonary capillary bed by venous blood
-diffusion of CO2 into the alveoli
-removal of CO2 from lungs by ventilation
