ABG, PFT, heart sounds Flashcards
(48 cards)
List the normal values for the following:
- pH
- pO2
- pCO2
- HCO3
- BE
- saO2
- pH = 7.35-7.45
- pO2 = 80-100 mmHg
- pCO2 = 35-45 mmHg
- HCO3 = 22-26 mEq/L
- BE = -2 - +2 mEq/L
- saO2 = 95-100%
What is step one of interpreting ABG?
Determine if pH value reflects acidemia or alkalemia
- above or below 7.4
What is step two of interpreting ABG?
Classify the pathophysiologic state on the basis of the relationship between pH and PaCO2 values
- inverse relationship = respiratory
- direct relationship = metabolic
What is step three of interpreting ABG?
Determine the adequacy of alveolar ventilation on basis of PaCO2 value.
- < 30 mmHg= Alveolar hyperventilation
- 30-50 mmHg= Adequate alveolar ventilation
- > 50mmHg= Ventilatory failure
What is step four of interpreting ABG?
Determine the Extent of respiratory and metabolic components.
- absolute value of difference between reported PaCO2 and 40; Divide by 100
- Subtract half of this value from 7.4 if reported PCO2 is > 40; Add the entire value to 7.4 if the reported PaCO2 is < than 40.
- Classify problem as “ACUTE” if reported pH is the same as or farther from normal than expected pH; Classify as “CHRONIC” if the reported pH is closer to normal than expected pH
What is step five of interpreting ABG?
Classify if compensated, partially compensated, or uncompensated
- if pH is normal and PaCO2 and HCO3 are BOTH abnormal, then the patient is compensated
- If pH is abnormal and PaCO2 and HCO3– are BOTH abnormal, then the patient is partially compensated
- If pH is abnormal, and either PaCO2 OR HCO3– are abnormal, then the patient is uncompensated
What causes a right shift in the oxygen dissociation curve?
conditions that enhance release of oxygen
- increased CO2
- Increased DPG 2,3
- Increased exercise
- Decreased pH
- Increased altitude
- increased temperature
What causes a left shift in the oxygen dissociation curve?
conditions that keep oxygen tightly attached to Hb
- decreased CO2
- decreased body temp
- increased pH
What are the levels of oxygen that indicate hypoxemia?
60-80 mm Hg: Mild hypoxemia
40-60 mm Hg: Moderate hypoxemia
< 40 mm Hg: Severe hypoxemia
Normal range:
- adults 60-80 mmHg
- infants 40-70 mmHg
What is the first thing to do when evaluating PFTs?
Look at the time volume plot to determine acceptability
- check for variable effort, cough, early glottic closure
- 6s of smooth continuous exhalation and/or a plateau in the volume time curve of at least 1s
- should have normal early peak, no abrupt cessation of flow, no sharp sudden spikes
What are the lung auscultation sites on the R anterior side of the body?
- R upper lobe apical segment
- R upper lobe anterior segment
- R middle lobe medial segment
- R middle lobe lateral segment
- R lower lobe anterior basilar segment
What are the lung auscultation sites on the L anterior side of the body?
- L upper lobe apical segment
- L upper lobe anterior segment
- L lower lobe anterior basilar segment
What are the lung auscultation sites on the L posterior side of the body?
- L upper lobe posterior segment
- L lower lobe superior basilar segment
- L lower lobe posterior basilar segment
- L lower lobe lateral basilar segment
What are the lung auscultation sites on the R posterior side of the body?
- R upper lobe posterior segment
- R lower lobe superior basilar segment
- R lower lobe posterior basilar segment
- R lower lobe lateral basilar segment
- lingular segment under armpitish area
Values for FVC and FEV1 that are over ___ of predicted are defined as within the normal range
80%
The FEV1/FVC ratio is expressed as a percentage, and a normal young individual is able to forcibly expire at least ___ of his/her vital capacity in one second.
A ratio under ___ suggests underlying obstructive physiology; however, the FEV1/FVC ratio declines as a normal sequelae of aging.
80% ; 70%
- reduced ratio is the primary criteria for diagnosing obstructive lung disease
What would the FEV1 values be to indicate normal, mild, moderate, and severe obstruction?
normal = >80% mild = 65-80% moderate = 50-65% severe = <50%
What shape do flow volume curves make when there is an obstruction
there is a rapid peak then curve descends more quickly than normal and takes on a concave shape, reflected by a marked decrease in FEF 25-75
What values are reduced proportionately with restrictive lung disease?
FEV1 and FVC
- note, FEV1/FVC ratio will be normal or even elevated; can’t get air in but can get it out
What differences will you see on flow volume loop for restrictive disease?
the shape will be the same, but the curve will be much smaller
How do you interpret PFT values?
- look if FEV1 is normal (>80%), or abnormal (<80%)
- look at FEV1/FVC ratio (<80% = obstruction, >80% = possible restriction)
- Look at FVC (>80% = pure obstruction, <80% = can’t r/o concurrent restriction)
What does a thrill on the R base of the heart indicate?
- Aortic stenosis
2. Systemic hypertension
What does a thrill on the L of the heart indicate?
- pulmonic stenosis
2. pulmonic hypertension
What does a heave on the L lower sternal border indicate?
- ventricular hypertrophy
2. chronic lung disease