* This is the Professional Version. *
Cardiopulmonary Resuscitation in Infants and Children
Despite the use of CPR, mortality rates for cardiac arrest (see Cardiac Arrest) are 80 to 97% for infants and children. The mortality rate is almost 25% for respiratory arrest alone. Neurologic outcome is often severely compromised.
About 50 to 65% of children requiring CPR are < 1 yr; of these, most are < 6 mo. About 6% of neonates require resuscitation at delivery (see Neonatal Resuscitation); the incidence increases significantly if birth weight is < 1500 g.
Standardized outcome guidelines should be followed in reporting outcomes of CPR in children; eg, the modified Pittsburgh Outcome Categories Scale reflects cerebral and overall performance (see Pediatric Cerebral Performance Category Scale*).
Pediatric Cerebral Performance Category Scale*
Standards and guidelines for CPR from the American Heart Association are followed (see see Figure: CPR Techniques for Health Care Practitioners). For protocol after a person has collapsed with possible cardiac arrest, see Cardiopulmonary Resuscitation (CPR) in Adults : Overview and see Cardiopulmonary Resuscitation (CPR) in Adults : Circulation.
After CPR has been started, defibrillation (see Cardiopulmonary Resuscitation (CPR) in Adults : Defibrillation) and identification of the underlying cardiac rhythm (see Cardiopulmonary Resuscitation (CPR) in Adults : Monitor and IV) are done.
Bradycardia in a distressed child is a sign of impending cardiac arrest. Neonates, infants, and young children are more likely to develop bradycardia caused by hypoxemia, whereas older children initially tend to have tachycardia. An infant or child with a heart rate < 60/min and signs of poor perfusion that do not rise with ventilatory support should have cardiac compressions (see see Figure: Chest compression.). Bradycardia secondary to heart block is unusual.
After adequate oxygenation and ventilation, epinephrine is the drug of choice (see Cardiopulmonary Resuscitation (CPR) in Adults : First-line drugs).
BP should be measured with an appropriate-sized cuff, but direct invasive arterial BP monitoring is mandatory in severely compromised children.
Because BP varies with age, an easy guideline to remember the lower limits of normal for systolic BP (< 5th percentile) by age is as follows: < 1 mo, 60 mm Hg; 1 mo to 1 yr, 70 mm Hg; and > 1 yr, 70 + (2 × age in yr). Thus, in a 5-yr-old child, hypotension would be defined by a BP of < 80 mm Hg (70 + [2 × 5]). Of significant importance is that children maintain BP longer because of stronger compensatory mechanisms (increased heart rate, increased systemic vascular resistance). Once hypotension occurs, cardiorespiratory arrest may rapidly follow. All effort should be made to start treatment when compensatory signs of shock (eg, increased heart rate, cool extremities, capillary refill > 2 sec, poor peripheral pulses) are present but before hypotension develops.
Equipment size, drug dosage, and CPR parameters vary with patient age and weight (see CPR Techniques for Health Care Practitioners, see Table: Drugs for Resuscitation*, and see Table: Guide to Pediatric Resuscitation—Mechanical Measures). Size-variable equipment includes defibrillator paddles or electrode pads, masks, ventilation bags, airways, laryngoscope blades, endotracheal tubes, and suction catheters. Weight should be measured rather than guessed; alternatively, commercially available measuring tapes that are calibrated to read standard patient weight based on body length can be used. Some tapes are printed with the recommended drug dose and equipment size for each weight. Dosages should be rounded down; eg, a 2 ½-yr-old child should receive the dose for a 2-yr-old child.
Guide to Pediatric Resuscitation—Mechanical Measures
Susceptibility to heat loss is greater in infants and children because of a large surface area relative to body mass and less subcutaneous tissue. A neutral external thermal environment is crucial during CPR and postresuscitation and may range from 36.5° C in a neonate to 35° C in a child. Hypothermia with core temperature < 35° C makes resuscitation more difficult (distinct from the beneficial effects of postresuscitation hypothermia Postresuscitative Care : Neurologic support).
Upper airway anatomy is different in children. The head is large with a small face, mandible, and external nares, and the neck is relatively short. The tongue is large relative to the mouth, and the larynx lies higher in the neck and is angled more anteriorly. The epiglottis is long, and the narrowest portion of the trachea is inferior to the vocal cords at the cricoid ring, allowing the use of uncuffed endotracheal tubes. In younger children, a straight laryngoscope blade generally allows better visualization of the vocal cords than a curved blade because the larynx is more anterior and the epiglottis is more floppy and redundant.
In asystole, atropine and pacing are not used.
VF and pulseless VT occur in only about 15 to 20% of cardiac arrests. Vasopressin is not indicated. When cardioversion is used, the absolute energy dose is less than that for adults; waveform can be biphasic (preferred) or monophasic (see Guide to Pediatric Resuscitation—Mechanical Measures). For either waveform, the recommended energy dose is 2 joules/kg for the first shock, increasing to 4 joules/kg for subsequent attempts (if necessary—see Cardiopulmonary Resuscitation (CPR) in Adults : Defibrillation).
Automated external defibrillators (AEDs) with adult cables may be used for children as young as 1 yr, but an AED with pediatric cables (maximum biphasic shock of 50 joules) is preferred for children between 1 yr and 8 yr. There is insufficient evidence to recommend for or against the use of AEDs in children < 1 yr. For pad placement, see Cardiopulmonary Resuscitation (CPR) in Adults : Defibrillation.
* This is the Professional Version. *