14.7
運動負荷試験
概要
運動負荷試験は、一般的にトレッドミル試験として知られ、心血管機能を評価し、心臓病を診断するために使用される非侵襲的手順です。
定義
運動負荷試験は、トレッドミルまたはエアロバイクを使用して、運動に対する心臓の反応を測定します。胸部電極は、心電図を介して心臓の電気的活動を記録し、血圧は定期的に監…
運動負荷テストは、トレッドミルやエアロバイクを使用して運動に対する心臓の反応を測定することにより、心血管機能を評価し、心臓の状態を診断します。
検査の前に、看護師は患者に手順について通知し、快適な服装と運動靴を着用するように指示し、患者がカフェイン、アルコール、タバコを避けながら3時間絶食することを確認します 24時間前。
看護師は 10 本の ECG リードを取り付け、前胸部リードを標準位置に配置します。次に、左右の腕電極を鎖骨の2cm下に配置し、左右の脚電極を胴体下部の胸郭の下に配置します。
テスト中、運動は低強度のウォームアップフェーズから始まり、ECG、心拍数、血圧を継続的にモニタリングしながら徐々に増加します。
ECGの大幅な変化が発生した場合、または胸痛や呼吸困難などの症状が現れた場合、テストは目標心拍数で停止します。
陰性の結果では、ECGの変化は示されていません。肯定的な解釈には、STセグメントの抑制、T波逆転、または虚血または不整脈を示す他のECG変化が含まれる場合があり、これらはさらなる治療を必要とする可能性があります。.
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Q1: What is the purpose of an exercise stress test?
An exercise stress test evaluates cardiovascular function and diagnoses heart conditions by measuring the heart's response to exertion using a treadmill or stationary bicycle. The test discovers coronary artery disease symptoms, assesses existing heart condition severity, determines safe exercise levels, and evaluates the effectiveness of heart treatments.
Q2: How should patients prepare for an exercise stress test?
Patients should wear comfortable clothing and athletic shoes, fast for three hours before the test, and avoid caffeine, alcohol, and tobacco for 24 hours prior. Some medications like beta-blockers and calcium channel blockers may need to be paused 48 hours before testing. The nurse cleans the skin and obtains a resting 12-lead ECG for comparison.
Q3: What parameters are monitored during an exercise stress test?
During the test, continuous monitoring includes electrocardiogram (ECG) to detect ischemic changes and arrhythmias, heart rate to ensure target levels are reached, blood pressure to assess cardiovascular response, and symptoms like chest pain or dyspnea. Physical appearance, skin color, sweating, and perceived exertion are also observed throughout the procedure.
Q4: When does an exercise stress test stop?
The test stops when the patient reaches their target heart rate, which is 85% of maximum heart rate calculated by subtracting age from 220. It also terminates if significant ECG changes occur or symptoms develop, including severe chest pain, dyspnea, dizziness, leg cramps, or other abnormalities requiring immediate cessation.
Q5: What do positive and negative exercise stress test results indicate?
A negative result shows no ECG changes, indicating normal heart function during exertion. A positive result may include ST-segment depression, T-wave inversion, or other ECG changes indicating myocardial ischemia or arrhythmia, which may require further diagnostic testing or treatment interventions.
Q6: What happens after the exercise stress test is completed?
After exercise, the patient is monitored for 10 to 15 minutes until heart rate returns to normal. Monitoring continues until the patient is stable with no concerning symptoms. If myocardial ischemia signs like chest pain or ECG changes such as ST-segment depression or T-wave inversion occur, additional monitoring and interventions may be necessary.
Q7: What are the risks associated with exercise stress testing?
Stress tests are generally safe, but minimal risks include chest pain, fainting, or rarely myocardial infarction. Medical personnel and emergency equipment are available throughout the procedure to manage adverse events. Patients are informed about potential post-test symptoms and specific instructions for abnormal results.