Developed by Robert A. Bruce, the Bruce protocol is a diagnostic test administered primarily as part of a cardiology exam. During this unique cardiac function test, patients are required to walk on a treadmill for several minutes at various speeds and inclines. As a result of this exam, doctors are better able to detect or predict heart conditions such as angina and coronary artery disease.
Also known as exercise tolerance or exercise testing, the Bruce protocol is often used to diagnose patients who have previously complained of chest pain or who have a history of heart disease. The test is also useful in helping to evaluate or diagnose lung diseases. While other exercise stress tests are sometimes administered, doctors largely consider the Bruce protocol to be a thoroughly accurate instrument in diagnosing cardiovascular and respiratory problems.
During the Bruce protocol, patients are tested in seven different stages, each consisting of three-minute intervals. At the earliest stage a patient is asked to walk a treadmill at a slow pace with a minor incline while connected to instruments used to record such vital signs as blood pressure and heart rate. As the test advances, the incline is slowly increased as is the treadmill speed. The total time spent on the Bruce protocol is intended to be varies depending on whether the patient is unable to complete the test due to chest pain, dizziness, extreme fatigue or drastic changes in blood pressure. If any of these conditions occurs, the test is immediately halted.
Electrocardiographs are checked at the completion of each stage within the test to monitor heart function, and a patient’s blood pressure is periodically evaluated, as well. It is also not unusual for a test to be stopped before completion due to the feedback received from the medical instruments used to monitor a patient’s vital signs. While vital signs may indicate that a patient is in real danger if continuing exercise stress, tests are often stopped due to an otherwise healthy patient’s lack of physical fitness, which literally prohibits her or him from physically completing all seven stages of the Bruce protocol.
Whether the Bruce protocol is stopped due to a patient’s vital signs or physical inability to complete it, heart and blood pressure monitoring continues for several minutes. Such helps doctors understand the changes that are taking place in a person’s cardiovascular system after rigorous exercise. For several minutes immediately following a test, patients may still feel dizziness or shortness of breath and heart arrhythmias may still occur.