Monitoring & Normal Values

Question 1

Normal RA Pressure

Answer 1

0-5mmHg

This is the same as CVP

Question 2

Normal RV pressure

Answer 2

20-25/0-5mmHg

Question 3

Normal PA Pressure

Answer 3

20-25/10-15mmHg

The diastolic pressure is raised compared to the RV due to the presence of the pulmonary valve

Question 4

Normal Capillary Wedge Pressure

Answer 4

6-12mmHg

This is lower than the PA diastolic pressure to ensure forward flow

Question 5

Stroke Distance (in regards to oesophageal doppler)

Answer 5

Stroke distance is the area under the velocity time curve

SD x area = Stroke Volume

An increase of <5-10% following a fluid bolus suggests a plateau in the Starling curve for that patient has been reached.

Question 6

Peak Velocity (in regards to oesophageal doppler)

Answer 6

Peak velocity provides a good estimate of LV contractility.

It falls with increasing age (90-120 at age 20y, falling to 50-80cm/s at age 70)

Question 7

Flow time corrected (FTc; in regards to oesophageal doppler)

Answer 7

Corrected flow time is the duration of flow of blood in the aorta corrected for heart rate.

A normal FTc is 330-360ms.
It is increased in vasodilation and reduced in vasoconstriction (and therefore in hypovolaemia)