A4 Cardiopulmonary 1

Front 1

Spirometry measure what capacity?

Back 1

vital capacity

Front 2

Normal FEV1/FVC ratio

Back 2

80%

Front 3

Value of FEV1/FVC for restrictive

Back 3

above 80%; can be normal

rEstrictive = Elevated
Obstructive = lOw

Front 4

Value of FEV1/FVC for obstructive

Back 4

below 75-80%


rEstrictive = Elevated
Obstructive = lOw

Front 5

Five causes of restrictive pattern of lung disease

Back 5

Fibrosis
pneumoconiosis (asbestosis, coal miners)
sarcoidosis

neuromuscular disease (ALS, MD)
chest wall abnormalities (obesity, kyphoscoliosis)

Front 6

labs/PFT results that show a response to bronchodilator that is + for asthma

Back 6

increase in FEV1 and/or FEV of 12% or 200 ml

Front 7

intrathoracic lesion shows what on PFT?

Back 7

intrathoracic = inspiration OK on flow loop, but expiration flattened

inspiration pulls the lesion apart, but expiration pushes it together, causes obstruction

Front 8

extrathoracic lesion shows what on PFTs?

Back 8

extrathoracic = expiration OK on flow loop, but inspiration flattened

expiration pushes lesion open, but inspiration sucks it closed

Front 9

Formula for calculating lung volume with nitrogen or helium

Back 9

C1V1 = C2V2

You will know the concentration and volume of the introduced gas, and can measure the concentration of exhaled gas; calculate the missing parameter (lumg volume)

Front 10

Gas (He, N) determination of lung volume will underestimate volume if patient has [obstructive, restrictive] disease.

Back 10

obstructive

(air trapping)

Front 11

What lung volumes are changed with obstructive disease?

Back 11

Air trapping = increased residual volume

This also increases functional reserve and total lung volume.

The RV/TLC ratio will be increased because of larger residual volume

Front 12

What are three things that can increase diffusing capacity and give a mistaken reading?

Back 12

obesity
asthma
polycythemia

Front 13

What are the four steps to interpreting PFTs?

Back 13

1. FEV1/FVC ratio: if below lower limit of normal (80%), obstructive
2. FVC: if below LLN, this will confirm restrictive in the ratio was normal, and will suggest a mixed condition if the ratio was low.
3. TLC and RV, if available. A decreased TLC will confirm restrictive if the ratio was normal or high; a decreased TLC with obstructive condition (low ratio) will diagnose a MIXED condition (obstructive + restrictive). If RV and TLC are high in an obstructive condition, this shows air trapping.
4. DLCO. Reduced DLCO in restrictive suggests chest wall or neuromuscular problem. Reduced DLCO in obstructive suggests COPD/emphysema rather than asthma. Reduced DLCO in normal ratio and TLC suggests pulmonary hypertension or early ILD.

Front 14

Normal FEV1/FVC
Normal lung volumes
reduced DLCO

Back 14

pulmonary hypertension
early ILD

Front 15

Low FEV1/FVC
Normal lung volumes (TLC, FVC)
Reduced DLCO

Back 15

COPD, emphysema

Front 16

FEV1/FVC low (<80%)
FVC low (<80%)
TLC low (<80%)
DLCO low (<60)

Back 16

mixed obstructive and restrictive

Front 17

FEV1/FVC normal
FVC low (<75%)

Back 17

restrictive

Front 18

FEV1/FVC normal
FVC normal (>80%)

Back 18

normal

Front 19

FEV1/FVC normal
FVC normal
but symptomatic, wheezing
reduced peak flow

Back 19

possible asthma
but examine flow loop for intrathoracic or extrathoracic restriction

Front 20

Consider for restrictive pattern + reduced DLCO

Back 20

pneumonitis
interstitial lung disease

Front 21

Hypovolemic hyponatremia: goal sodium?

Back 21

120 (safe range)

Front 22

Hypovolemic hyponatremia: limit on repletion

Back 22

12 meq first 24 hours
18 meq first 48 hours

Front 23

hyponatremia: why order uric acid?

Back 23

uric acid is very low in SIADH

Front 24

Hyponatremia:
urine sodium high (>20)
significance?

Back 24

If urine sodium is high, urine sodium >20 (20 - 25). Sodium is being excreted correctly, but water retained (SIADH).
Not perfect: Note that low sodium intake can give falsely low urine sodium in SIADH.

Front 25

Hyponatremia:
urine sodium low (<20)
significance?

Back 25

If urine sodium is low ( < 20, or < 25 in some texts), hypovolemia is likely cause.

Front 26

Treatment for SIADH

Back 26

fluid restriction (mild)
demeclocycline (ADH receptor antagonist.`