Unit 3 Week 9 Pulmonary Tests and Diagnostic Procedures Flashcards
ABGs are crucial to the assessments of problems related to:
acid-base balance
alveolar ventilation
oxygenation
what does a typical ABG report contain?
arterial pH, partial pressures of CO2, O2, oxygen saturation, bicarbonate concentration, and base excess
what is the normal value for ABG pH?
7.4
7.35-7.45
what is the normal value for ABG PCO2?
40
35-45
what is the normal value for ABG PO2?
97
>80
what is the normal value for ABG Hco3-?
24
22-28
what is the normal value for ABG O2 saturation?
97%
>95%
PaCO2 directly reflects adequacy of:
alveolar ventilation
what PaCO2 level is considered hyperventilation? hypoventilation? ventilatory failure?
- Hyperventilation—PaCO2 <40 mm Hg
- Hypoventilation—PaCO2 >40 mm Hg
- Ventilatory failure—PaCO2 >50 mm Hg
what is normal human blood pH? what is considered acidemia? alkalemia?
normal: 7.4
acidemia: <7.4
alkalemia: >7.4
what are the causes of respiratory acidosis?
hypoventilation: over sedation, head trauma, NM disorders, cardiac arrest, chest trauma, COPD, pneumonia
what are common symptoms of respiratory acidosis?
tachycardia, confusion, drowsiness, dizziness, minimal if chronic (COPD)
what are the causes of respiratory alkalosis?
hyperventilation: anxiety/fear/panic, excessive mechanical ventilation
hypoxemia
CHF
PE
what are the common symptoms of respiratory alkalosis?
numbness and tingling of lips and extremities, dizziness, and sinus arrhythmias
what are the causes of metabolic acidosis?
increased production of acids: ketoacidosis or lactic acidosis
decreased acid excretion by kidneys: renal failure
loss of alkali: diarrhea
what are the common symptoms of metabolic acidosis?
DOE, deep rapid breathing, disorientation, fatigue, weakness
what are the causes of metabolic alkalosis?
loss of acid from GI tract or kidney: vomiting or laxative abuse
increased HCO3 reabsorption or generation: excessive use of antacids
what are the common symptoms of metabolic alkalosis?
tetany, hypertonic muscles, numbness, asymptomatic
If a patient has acidosis/alkalosis with increased PaCO2, what type of acidosis do they likely have?
respiratory acidosis/alkalosis
If a patient has acidosis/alkalosis with decreased PaCO2, what type of acidosis do they likely have?
metabolic acidosis/alkalosis
How do you tell if ABGs are compensated or non-compensated?
if pH is off, it is non-compensated. If pH is normal = compensated
When PaCO2 and HCO3- are both out of normal range, (high or low) then the body is trying to compensate.
If one (PaCO2 or HCO3-) is normal, and other is out of normal range, either it is recent onset (acute) or the body cannot compensate
What are the three stages of hypxemia?
▪ Mild Hypoxemia: PaO2 = 60 – 80 mmHg
▪ Moderate Hypoxia: PaO2 = 40 – 60 mmHg
▪ Severe Hypoxia: PaO2 = <40 mmHg
