Real-Life Decision Making
You are a newly graduated exercise physiologist who works in the cardiac
rehabilitation ward of a large hospital. You work with patients, helping them
strengthen their bodies and hearts so they can lead a normal life again.
Today, you have a number of patients you'll be working with. They
will all undergo a graded exercise test, or GXT. You notice that you have
15 patients to get through the testing today -- that's quite a few considering
each test takes between 30 and 45 minutes to complete. Hopefully, there won't
be any delays with any of the tests. It's going to be difficult enough
to try and squeeze them all in.
For a patient to take a GXT, they must walk or run on a treadmill.
As each patient's workload becomes progressively harder, you monitor
the changes in both the patient's blood pressure and heart rate.
Before the first patient begins testing, you record both her pulse and
blood pressure. The electrical activity of her heart (her resting EKG) is
also recorded.
Before the patient actually begins the test, you explain what information
the test will provide and how you can use the data. Then you tell her how
the test will work and what you expect to see.
You explain to her that every few minutes, you will increase the speed
and grade of the treadmill, thereby increasing her workload. Her blood pressure
and her heart rate should rise accordingly. If they don't rise (or if
only her heart rate rises) it could be a sign of ischemia. Ischemia is a condition
that means the patient's tissue is not receiving enough oxygen due to
insufficient blood flow.
You ask the patient to begin walking. After three minutes, you check her
blood pressure and heart rate. Both are increasing steadily as they should.
After another three minutes, you check again. Both the patient's heart
rate and blood pressure are still rising, although not as much as you expected.
You keep a close eye on the monitor where the results are shown. After two
minutes, you notice there has been no increase in the blood pressure at all.
You've never actually seen a GXT gives these kinds of results before,
but you decide to wait two more minutes in case the patient's blood pressure
changes.
Two more minutes go by and the patient's blood pressure isn't
looking good. Her systolic blood pressure has now dropped by 10 mmHg. This
drop could very possibly indicate ischemia.
What do you do?