2. Acid-Base Flashcards
pH
Hydrogen (indirect measurement of hydrogen ion concentration)
• the greater concentration of H ion more acidic and the lower the pH; less concentration more alkaline and the higher the pH
• anything 6.8-7.8 = no life
Reflection of the balance between carbonic acid and bicarbonate
carbonic acid: exhalable; results from aerobic metabolism of glucose (acid regulated by the lungs) and bicarbonate: nonexhalable; results from aerobic metabolism of fats and proteins and anaerobic metabolism of glucose (base regulated by the kidneys)
respiratory system acidosis
you increase respiratory rate (hyperventilation) you eliminate, “blow off,” CO2 (acid) therefore decreasing your CO2 acid—giving you ALKLAOSIS by reducing acid
respiratory system alkalosis
you decrease your respiratory rate (hypoventilation) you retain CO2 (acid) therefore increasing your CO2 (acid)—giving you ACIDOSIS by increasing acid load
Renal system acidosis
You have Acidosis when you have excess H+ and decreased HCO3- causing a decrease in pH. The Kidneys try to adjust for this by excreting H+ and retaining HCO3- base.
renal system alkalosis
You have Alkalosis when H+ decreases and you have excess (or increased) HCO3- base. The kidneys excrete HCO3- (base) and retain H+ to compensate. The respiratory system tries to compensate with hypoventilation to retain CO2 (acid)
pH normal*
7.35-7.45
pH decreased*
Acidosis
pH increased*
Alkalosis
pCO2 normal*
35-45
pCO2 decreased*
Alkalosis
pCO2 increased*
Acidosis
HCO3 normal*
22-26
HCO3 decreased*
Acidosis
HCO3 increased*
Alkalosis
pO2 normal*
80-100
pO2 decreased*
hypoxemia
pO2 increased*
O2 therapy
SaO2 normal*
85-100%
SaO2 decreased*
hypoxemia
metabolic acidosis
Decrease pH (lower than 7.35), decrease HCO3 (lower than 22) (If PaCO2 decreased then compensating)
metabolic acidosis caused by direct
direct loss of bicarb (too much acid, too little bicarb)
metabolic acidosis causes
increase H production(DKA, hyper-metabolism)
decrease H elimination (renal failure)
decrease HCO3 production (dehydration, liver failure)
increase HCO3 elimination (diarrhea, fistulas
metabolic acidosis s/s
o Associate with: diarrhea, diuretics, TPN, DKA, early renal insufficient, excessive chloride
o Symptoms: headache, drowsiness, pherial vasodilaiton especially pH below 7, drop in blood pressure, cold clammy, dysrythemia, shock
metabolic acidosis treatment
bicarb, through IV, monitor K level closely
o chronic state: pts with renal failure may need hemodialysis
Metabolic alkalosis
increase pH (above 7.45) increase bicarb (above 26)
Metabolic alkalosis causes
increase bicarb (anatacids, admin of Na bicarb) decreaes H (NG suctioning, vomitting, hypercortisolism)
Metabolic alkalosis most common cause
vomiting, GI suctioning
Metabolic alkalosis s/s
related to hypocalcemia; tingling fingers and toes, n/v/d, dizziness, anxious, seizures, hypertonic muscles, tremors, muscle cramping, low calcium levels, dysrhythmias
Metabolic alkalosis treatment
correct underlying cause, monitor I&O carefully, may give sodium chloride (NS), treat low K – done with K/Chloride mixture, give tagament
respiratory acidosis
Decrease pH (less 7.35), increase PaCO2 (greater than 48)
respiratory acidosis is an
emergency inadequate ventilation, examples (pumeono thorax, overdose, obstructive sleep apnea, pulmonary edema, excessive O2, prolonged bed rest where actelsis, improper ventilator symptoms)
respiratory acidosis s/s
- At first: increase heart rate, increase respirations, increase blood pressure, mental cloudiness, PCO2 great than 60
- As progresses – respirations shallow, headache, elevated K, ventricular fiblar, capillary edema, dilated blood vessels
- Chronic state: COPD (milder symptoms)
respiratory acidosis treatment
improve ventilation – bronchilodilators, antibiotics – infection, thrombolytics; pulmonary hygeiene, incourage fluids to keep secretions thin – 2-3L per day, O2 as needed mechanical ventilation, gradual CO2 drop, high semi flowlers position
respiratory acidosis causes
Hypoventilation, CNS depression, Headache, tachycardia, diaphoresis
Respiratory alkalosis
Increase pH (greater 7.45), decrease PaCO2 (less than 35)
Respiratory alkalosis causes
Hyperventilation, gram-negative bacteremia, respiratory stimulation
Respiratory alkalosis most common caused by
most caused by hyperventilation – decrease carbonic acid, anxiety, hypocemia, aspirin toxicity, gram negative bacteria, inaprpriate ventialar settings
Respiratory alkalosis s/s
respirations increase and deep, decrease blood pressure, low K, numbness, tingling, light headedness, inability to concentrate, COC, riging in ear
Respiratory alkalosis treatment
slow down respirations, breath in paper bag, sedatives treat underlying cause
