Heart Biomarker Evaluation in Apnea Treatment

3.3.4.1 Explaining the Procedure

7. Preparing a subject for testing:
   • Explain the procedure to the subject:
     • See the sample Script at the end of this procedure manual. The purpose of the study is to test how reactive the subject’s blood vessels are. Healthy blood vessels tend to respond with changes in blood flow when a blood pressure cuff is inflated. We will make this assessment by measuring changes in the blood flow in the finger tips using a sensor worn over the finger tip. It will be important to compare the blood flow in the finger of one hand where a blood pressure cuff was used to temporarily reduce blood flow and compare that to the finger of a hand where a blood pressure cuff was not placed on the arm.
     • Note that the occlusion is harmless but may be uncomfortable
     • Some markings on the skin from the BP cuff are possible but harmless and will pass with time.
     • Strange sensations (such as tingling in your fingers) during and after the occlusion are common and transient.
     • Instruct the subject that throughout the test he/she should refrain from talking, except in an emergency.
     • Ask the participant to relax and not to stretch or move the fingers during testing and to keep fingers from touching each other and not touching anything.
     • The test is not over when the occluding cuff is deflated and the subject should not move until instructed to do so.