Trường hợp điện khử cực bắt đầu trong cơ tim? Điện khử cực bắt đầu từ nút xoang nhĩ. Nút xoang nhĩ nằm ở đâu? Tại chỗ nối của cấp trên tĩnh mạch chủ và tâm nhĩ phải. Sau khi rời khỏi nút xoang nhĩ, con đường của quá trình khử cực điện là gì? Nó tiến bộ thông qua mô tâm nhĩ và những con đường internodal mô nối truyền nhĩ thất. | 68 PALS Pediatric Advanced Life Support Review o Where does electrical depolarization begin in the myocardium Electrical depolarization begins in the sinoatrial node. o Where is the sinoatrial node located At the junction of the superior vena cava and the right atrium. o After leaving the sinoatrial node what is the pathway of electrical depolarization It advances via atrial tissue and the internodal pathways to the atrioventricular junctional tissue. o What happens to depolarization at the atrioventricular junction It slows temporarily. o Where does it go then It then progresses via the bundle of His and its divisions to depolarize the ventricular myocardium. o What is the first deflection on the surface ECG called The P wave. o What does the P wave signify It represents the depolarization of both atria. o What does the PR interval represent The delay in conduction at the AV junction and the time to spread the impulse through the bundle of His. o What represents the depolarization of the ventricles The QRS complex. o What do the ST segment and the T wave represent Ventricular repolarization. o What are the two key factors in influencing differences in normal heart rate in children Age and physical activity. o What two primary pathological conditions may influence heart rate in children Fever and volume loss fluid loss . vomiting or diarrhea and hemorrhage . o T F A febrile infant with normal cardiovascular function can have a heart rate of 200 beats per minute or higher. True. These infants can have heart rates up to 200 beats per minute. CHAPTER 7 Cardiac Rhythm Disturbances 69 o When should you continuously monitor the ECG in children When they have evidence of respiratory or cardiovascular instability including children who have sustained a cardiopulmonary arrest. o What can the ECG tell you about the effectiveness of myocardial contractility and the quality of tissue perfusion Nothing. o With what must you correlate information derived from the ECG in the .
