Pediatric cardiopulmonary resuscitation.

Abstract

Outcomes following pediatric out-of-hospital arrests are much worse than in-hospital arrests. Survival to hospital discharge typically occurs in less than 10 % of these children, and many have severe neurological sequelae. These poor outcomes are in part because of prolonged periods of ‘no flow’ and in part because of specific diseases (e.g., traumatic cardiac arrest and sudden infant death syndrome [SIDS]). The major role of CPR is to supply vital organs and tissues with blood flow, oxygen and nutrients. Coronary perfusion pressure below 15 mmHg during CPR is a poor prognostic factor for a return of spontaneous circulation. The most critical elements are to “push hard” and “push fast”. Because there is no flow without chest compressions, it is important to minimize interruptions in chest compressions. The best ratio depends upon many factors including the compression rate, the tidal volume, the blood flow generated by compressions, and the time that compressions are interrupted to perform ventilations. A chest compression to ventilation ratio of 15:2 delivered the same minute ventilation as CPR with a chest compression to ventilation ratio of 5:1 in a manikin model of pediatric CPR, but the number of chest compressions delivered was 48 % higher with the 15:2 ratio. Intraosseous vascular access has largely replaced the need for endotracheal drug administration. Absorption of drugs into the circulation after endotracheal administration depends on dispersion over the respiratory mucosa, pulmonary blood fl ow, and the matching of the ventilation (drug dispersal) to perfusion. Myocardial dysfunction and vascular instability are common folowing resuscitation from cardiac arrest. Therefore in infants and children with cardiovascular dysfunction after cardiac arrest it is reasonable to administer vasoactive drugs (epinephrine, dopamine, dobutamine and norepinephrine) titrated to improve myocardial function and organ perfusion. VF is an uncommon, but not rare, EKG rhythm during out-of-hospital pediatric cardiac arrests. The incidence of VF varies by setting and age. In special circumstances, such as tricyclic antidepressant overdose, cardiomyopathy, post-cardiac surgery, and prolonged QT syndromes, VF is a more likely rhythm during cardiac arrest. Commotio cordis, or mechanically-initiated VF due to relatively low-energy chest wall impact during a narrow window of repolarization (10-30 msec before the T wave peak in swine models) is reported predominantly in children 4-16 years old. Defibrillation (defined as termination of VF), is necessary for successful resuscitation from VF cardiac arrest. The goal of defibrillation is return of an organized electrical rhythm with pulse. Provision of high quality CPR can improve outcome and save lives. Because pediatric cardiac arrests are commonly due to progressive asphyxia and/or shock, the initial treatment of choice is prompt CPR. The earlier that VF can be diagnosed, the more successfully we can treat it. ECMO is commonly used for circulatory support in pediatric cardiac surgical patients with refractory low cardiac output, persistent hypoxemia, arrhythmias, cardiac arrest, or failure to wean from CPB. CPR guidelines recommend target values for selected CPR parameters related to rate and depth of chest compressions and ventilations, avoidance of CPRfree intervals, and complete release of sternal pressure between compressions. An approach to “Push Hard, Push Fast, Minimize Interruptions, Allow Full Chest Recoil and Don’t Over-ventilate” can markedly improve myocardial, cerebral, and systemic perfusion, and will likely improve outcomes. Outcomes from pediatric cardiac arrest and CPR appear to be improving. The evolution of practice to understand the pathophysiology and timing, intensity, duration, and variability of the hypoxic-ischemic insult leads to goal directed therapy gated to the phase of cardiac arrest encountered.