MANUAL PHYSIOLOGY PRACTICAL - Repository:The Medical ...

FM/UOJ
The mass of the tissue in the forearm is determined by displacement of water by
the forearm up to the level that was inserted into the plethysmograph. Since the bones
receive negligible blood supply the volume of the bones is deducted from the volume
of the fore arm and flow/min/100g tissue calculated.
Observation
Stick the tracing
Calculation
Increase of volume and the duration are determined from the tracing. Inspect
the tracing to observe the initial rising phase and a later stable phase when the veins
have become full. The initial rising phase is extended by extending the tracing. The
time is measured from the horizontal axis and the flow from the vertical axis.
If,
The increase in volume
The duration
Flow in T sec
Flow in 60 sec
= V ml
= T seconds
= V ml
= 60 x V ml/min
T
Results:
Circulation
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