Pediatric emergency medicine trisk 1723 1723
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (46.3 KB, 1 trang )
Management/Diagnostic Testing of Tachycardia. The gold standard for
arrhythmia diagnosis is a 12- or 15-lead EKG. Using the EKG, the rhythm may
be classified into narrow or wide, and regular or irregular. The mechanism can be
discerned from the rate and the P wave relationship to the QRS. Extremely
regular tachycardia suggests a re-entrant circuit as the mechanism. Any
irregularity of the rate or rhythm may reveal the mechanism of the arrhythmia and
therefore these irregularities should be recorded on an EKG for scrutiny after the
patient is stabilized.
When a patient presents to the ED with tachycardia a standard approach should
be taken. First, determine if the patient is stable or unstable. An unstable patient
should rapidly be prepared for cardioversion or defibrillation according to
Pediatric Advanced Life Support (PALS) guidelines. A simple rhythm strip
should be recorded through the external defibrillator. If the patient is pulseless,
high-quality CPR should be initiated, airway and IV access should be secured.
Unstable nonsinus tachycardia should be cardioverted or defibrillated.
Synchronization should be employed in all rhythms except ventricular fibrillation
(VF) to prevent the shock from being delivered at a vulnerable time on the T
wave, potentially inducing VF. If tachycardia persists, the shock should be
repeated with higher energy according to PALS guidelines (see Chapter 9
Cardiopulmonary Resuscitation ). After delivery of the shock, CPR should
resume immediately. One provider should check the rhythm strip while another
team member re-assesses the patient. If the rhythm has converted to normal sinus
rhythm and the patient is stable, obtain an EKG, and assess for CHF. The patient
should constantly be monitored for any deterioration in condition or change in
rhythm. Inotropes are arrhythmogenic, so if necessary they should be initiated
with care. Consult cardiology and admit to an intensive care unit skilled in care of
dysrhythmias.
If the patient is stable, obtain an EKG with long rhythm strip to determine
whether the QRS is narrow or wide and whether the rhythm is regular or
irregular. That information drives subsequent actions.
Narrow Complex, Irregular Tachycardia. An irregularly, irregular, narrow QRS
rhythm, is almost always atrial fibrillation (or less commonly, atrial flutter/IART
with variable conduction). These rhythms will respond to synchronized
cardioversion (0.5 to 1 J/kg), or medication for rate control. Due to the risk of
stroke, one should avoid cardioversion in a patient who has been in atrial
fibrillation for 48 hours or more, or who is unable to tell when tachycardia
started. Either beta-blockers or calcium channel blockers may be used (but not in
