Tests: ECGs, PFTs... Flashcards
Leads showing LATERAL MI
St elevation: I, aVL (also V5, V6)
reciprocal: II, III, aVF
Leads showing INFERIOR MI
ST-elevation: II, III, aVF
reciprocal: aVL
leads showing SEPTAL MI
ST elevation: V1, V2
leads showing ANTERIOR MI
ST elevation: V4, V5
* often w/ V-fib (common complication)
leads showing POSTERIOR MI
reciprocal change (ST depression): V1-V4 * "carousel" shaped pattern
Normal Jugular Venous Distention measurements
8 cm above sternal angle or less.
R atrium = 5 cm into body from sternal angle
location for palpating apical impulse
in 5th interspace, just medial to midclavicular line
= 1st 1/3 of systole
Bell of stethoscope used to hear
low pitched sounds
- diastolic murmur
- S3, S4
diaphragm of stethoscope used to hear
high pitched sounds
- S1 & S2 (*S1 longer than S2)
- ejection & midsystolic clicks
- aortic regurg. murmur
heart sounds (murmur) caused by
vibration of heart valves & heart system during valve closure or blood flow turbulence
possible causes of S2 splitting
- Variable splitting, w/ inspiration: physiologic, RBBB, pulmonary stenosis
- Fixed wide splitting: atrial septal defect
- Variable reversed splitting (“paradoxical”): LBBB, LV failure, HTN
midsystolic click indicates
systolic mitral valve prolapse,
* later w/ increased LV volume.
causes of S3 & S4
S3 = early rapid filling S4 = vigorous atrial contraction
likely causes of Ejection clicks
- bicuspid valve
- pulmonary stenosis
- dilatation of aorta or pulmonary artery
cause of opening snap
rheumatic mitral stenosis.
innocent flow murmur
twangy, crescendo-decrescendo systolic murmur;
from high flow through normal valves.
determining axis of heart on ECG
using limb leads:
lead w/ the most deflection = same axis
OR isoelectric lead = perpendicular to axis
(I = 0, II = +60, aVL = -30, III = 120, aVF = +90)
* >90 = R shift, <-30 = L shift.*
P wave > 2.5 in lead II
Right atrial enlargement
prolonged P wave on ECG (> 1 mm, negative @ end)
Left atrial enlargement,
P wave changes = in lead I, changes = early and negative
typical ABG results for pneumonia
Low V/Q –> hypoxemia due to focal shunt.
* may have increased PaCO2 if severe lung damage.
Characteristics of a “quality” sputum sample
> 25 WBCs and < 10 epithelial cells @ x100 magnification
often risk oral or other contamination when obtaining sample
obstructive disease PFT
FEV1/FVC < LLN = obstructive disease
(Mild: FEV1 > 70% predicted; Severe: < 50% predicted)
* high RV & often high TLC (bc air trapping)!
= slow emptying (bc decreased elastic recoil)
ie: asthma, COPD, upper airway obstruction
PFT for restrictive disease
TLC < 80% predicted w/ symmetrically low RV (not if just poor effort)
(also often low FVC and high FEV1/FVC).
ie: interstitial lung disease, pulmonary fibrosis
Variable Extrathoracic Upper airway obstruction
when tracheal P < atmospheric P w/ Inspiration (only, not expiration) –> trachea narrows.
==> reduced INspiratory limb (bottom) on Flow volume loop
ie: laryngeal tumor
Obstructive vs. Restrictive Flow Volume Loops
Obstructive: scooped out expiratory limb, otherwise normal shape
Restrictive: small, squished loop (shorter & earlier on horizontal axis)
Variable Intrathoracic Upper Airway obstruction
when pleural P > tracheal P => trachea narrows.
==> reduced EXpiratory limb (top) on Flow Volume Loop
Fixed Upper Airway obstruction
BOTH INspiratory & EXpiratory limbs reduced on flow volume loop
(could be intrathoracic or extrathoracic)
measuring RV (residual volume) of lung
- cannot measure directly bc RV = volume left after maximal expiration!
==> RV = FRC - ERV
(ERV = expiratory reserve volume)
Measuring TLC (total lung capacity)
1. body plethysmography
- Gas dilution
(neither very accurate)
DLCO
measures rate of gas transport from alveoli to hemoglobin
(aka: diffusion into blood)
* Low CO exhaled = high DLCO = normal. (high CO exhaled = bad)
- -> abnormal if decreased alveolar surface area or low hemoglobin
Aortic stenosis murmur & ECG
High, late, loud systolic murmur w/ S4.
ECG: strain & LVH
Mitral stenosis murmur & ECG
opening snap + soft diastolic murmur,
loud S1 & P2 (from pulm. htn);
ECG: broad biphasic P wave, RVH, +/- atrial fibrillation
