MANUAL PHYSIOLOGY PRACTICAL - Repository:The Medical ...

FM/UOJ
Experiment C 4
ISCHAEMIC PAIN
When the blood supply of an active organ is inadequate, there occurs a
crippling pain which is distinct from muscular fatigue and cramp. Since this is related
to ischaemia, it is called ischemic pain. Ischaemia can be absolute when a blood vessel
is completely blocked; it can be relative when the blood supply is less than required,
generally, as a result of partial obstruction of vessels. The pain of angina pectoris,
myocardial infarction pulmonary infarction and intermittent claudication of calf muscle
are caused by ischaemia
The aim of this practical is to study some aspects of the causation of this pain
and to give an experience of the nature of this pain to students. The efficacy of varying
combinations of exercise and arterial occlusion in producing ischaemic pain is assessed.
Principle:
Varying combinations of exercise and arterial occlusion are carried out in
producing ischaemic pain, in order to determine the role of each of these factors in the
production of the pain.
Apparatus:
a. A wooden rod, stop watch and sphygmomanometer cuff.
Procedure:
Students will work in pairs: One student will make the observations on the
other. The subject must be seated comfortably, with his right arm resting on a table.
The following procedures are to be carried out on the same arm in the given order,
allowing the arm to recover fully after each procedure before the next is begun.
A. Exercise the right forearm of the subject for four minutes, by gripping the
wooden rod in the manner mentioned above.
B. Occlude the circulation through the right arm for four minutes, without any
exercise. Describe the sensations in the arm during occlusion and on release of
pressure.
C. Now combine A and B by performing the exercise after occluding the
circulation in the arm. Note the time of onset of pain. Continue the exercises till
the pain is unbearable, and note the time again. Then release pressure. Note the
quality of pain and the time taken for the pain to disappear after the pressure is
released.
D. Repeat C but reduce the rate of exercise to once in two second.
E. Repeat C but increase the rate of exercise to twice every second.
F. Repeat C. When the pain is quite marked, stop the exercise but maintain the
pressure in the cuff for another minute and then release it.
Circulation
Page | 93