Pulmonary Capillary Wedge Pressure

Question 1

The ____ is also used to measure the pulmonary capillary wedge pressure (PCWP) (also called pulmonary artery wedge pressure).

Answer 1

pulmonary artery catheter

Question 2

___ is measured by slowly inflating the balloon via the balloon inflation port on the pulmonary artery catheter.

Answer 2

PCWP

Question 3

As the balloon inflates, the pulmonary arterial waveform on the monitor will change to the ____ .

Answer 3

wedged pressure waveform

Question 4

Proper inflation of the balloon usually requires no more than ___ ( ____depending on size of balloon) of air.

Answer 4

1.5 mL (0.75 to 1.5 mL

Question 5

The balloon is ___ as soon as the reading of PCWP is obtained.

Answer 5

deflated

Question 6

The ____ reading is typically taken at end-expiration for both spontaneous breathing and mechanically ventilated patients

Answer 6

PCWP

Question 7

This practice should be done consistently for consistent ____ measurements and meaningful interpretation of hemodynamic data.

Answer 7

PCWP

Question 8

____ reflects the left ventricular preload.

Answer 8

PCWP

Question 9

The components of the ____ waveform are similar to the CVP or right atrial wave- form.

Answer 9

PCWP

Question 10

the ___ wave of the PCWP waveform reflects left atrial contraction

Answer 10

a

Question 11

____ downslope represents the decrease in left atrial pressure following contraction.

Answer 11

x

Question 12

The ____ wave, if present, is seen along the x downslope, and it occurs during closure of the mitral valve.

Answer 12

c

Question 13

The ____ wave indicates left ventricular contraction and passive atrial filling.

Answer 13

v

Question 14

The ___ downslope is due to the decrease in blood volume and pressure following the opening of the mitral valve

Answer 14

y

Question 15

Increased PCWP measure- ments are often observed in conditions where ____ or ____ is present in the left heart

Answer 15

partial obstruction / excessive blood flow

Question 16

Two common changes in the PCWP waveform are the ___ and ___ waves.

Answer 16

a and v waves

Question 17

The __ wave of the PCWP waveform may be increased in conditions leading to higher resistance to left ventricular filling.

Answer 17

a

Question 18

The a wave of the PCWP waveform may be increased in conditions leading to higher resistance to left ventricular filling. Some examples are _____, ______, and ______.

Answer 18

mitral valve stenosis,
left ventricular hypervolemia or failure,
and decreased left ventricular compliance.

Question 19

The ____ wave of the PCWP waveform may be increased due to mitral valve insufficiency.

Answer 19

v

Question 20

The v wave of the PCWP waveform may be increased due to mitral valve insufficiency. This condition leads to ____ (backward flow) of blood from the left ventricle to the left atrium through the incompetent mitral valve.

Answer 20

regurgitation

Question 21

The normal range for PCWP is from ____.

Answer 21

8 to 12 mm Hg

Question 22

______ can affect wedge pressure readings since over distension of the alveoli com- presses the surrounding capillaries and raises the capillary and arterial pressures.

Answer 22

Positive pressure ventilation or PEEP

Question 23

A higher than normal wedge pressure may also be seen in ______.

Answer 23

left ventricular dysfunction

Question 24

This is because _____ causes backup of blood flow in the left heart and pulmonary circulation.

Answer 24

left ventricular failure

Question 25

A PCWP reading of _____along with a near- normal PAP suggests presence of left ventricular dysfunction or left heart failure.

Answer 25

≥18 mm Hg

Question 26

The ___ measurement may be used to distinguish cardiogenic and noncardio- genic pulmonary edema.

Answer 26

PCWP

Question 27

____ that is caused by left ventricular failure, the PCWP is usually elevated (≥18 mm Hg) along with a near-normal PAP.

Answer 27

pulmonary edema

Question 28

In pulmonary edema where the PCWP is normal, the cause may be ______ or an increase in ____ (e.g., ARDS).

Answer 28

acute pulmonary hypertension / capillary permeability

Question 29

~Increase in pulmonary blood flow Left heart pathology

~Mechanical factor

Give examples of

Answer 29

PCWP Increase /
Hypervolemia
Left ventricular failure;
Mitral valve disease Overwedging of balloon

Question 30

Mechanical ventilation
Decrease in pulmonary blood flow

Answer 30

PCWP Decrease /
PEEP
Hypovolemia

Question 31

Since ___ or ___ waveform may occur during inflation of the balloon, and it resembles that of a wedged pressure tracing, using the PCWP tracing alone on the monitor to verify the wedged position may not be always reliable.

Answer 31

artifact or dampened

Question 32

Three methods are available to confirm a properly wedged pulmonary artery catheter:

Answer 32

(1) PAP diastolic-PCWP gradient;
(2) postcapillary-mixed venous PO2 gradient; and
(3) postcapillary-mixed venous O2 saturation gradient.

Question 33

Under normal conditions, the PAP diastolic value is about _____ higher than the average wedge pressure of the same individual (PAP Diastolic-PCWP Gradient)

Answer 33

1 to 4 mm Hg

Question 34

However, the PAP diastolic value may be lower than actual with _____.

Answer 34

forceful spontaneous inspiratory efforts

Question 35

The PCWP may be higher than actual if there is significant downstream obstruction such as _____

Answer 35

mitral valve disease

Question 36

The PO2 of a blood gas sample from the distal opening of a properly wedged catheter should be at least ____ than that from a systemic artery.

Answer 36

19 mm Hg higher

Question 37

The PCO2 should be at least _____.

Answer 37

11 mm Hg lower

Question 38

These differences are expected because a ___ wedged catheter does not allow mixing of shunted venous blood with the postcapillary (oxygenated) blood.

Answer 38

properly

Question 39

This procedure may not be feasible for a hypovolemic patient because up to ___ of waste (mixed venous) blood sample may be required before reaching the postcapil- lary blood sample

Answer 39

40 mL

Question 40

This procedure may not be feasible for a hypovolemic patient because up to 40 mL of waste (mixed venous) blood sample may be required before reaching the postcapil- lary blood sample

Answer 40

Postcapillary-Mixed Venous PO2 Gradient.

Question 41

If the pulmonary artery catheter is capable of monitoring oxygen saturation by the oximetry method, the oxygen saturation value of a properly wedged catheter should be about ____ than the one recorded with the balloon deflated

Answer 41

20% higher

Question 42

If the pulmonary artery catheter is capable of monitoring oxygen saturation by the oximetry method, the oxygen saturation value of a properly wedged catheter should be about 20% higher than the one recorded with the balloon deflated

Answer 42

Postcapillary-Mixed Venous O2 Saturation Gradient.