The resuscitation of children differs from that of adults in a number of important ways. For example, the most common cause of primary cardiac arrest in adults is coronary artery disease, whereas respiratory failure and shock are more common causes among children and infants; hypoxemia, hypercapnia, and acidosis subsequently lead to bradycardia, hypotension, and secondary cardiac arrest in children. After resuscitation, survival to discharge may be greater among children and adolescents than in infants or adults.^1,2,3,4 The survival rate without devastating neurologic sequelae in children varies by age, ranging from 1% to 2% in infants and young children to 11% for adolescents in whom a shockable rhythm is more common; survival rates as high as 30% have been seen after sudden out-of-hospital witnessed ventricular fibrillation.^5,6,7 The best chance for a good outcome is to recognize impending respiratory failure or shock and intervene to prevent the development of cardiopulmonary arrest.

Age-related differences are important considerations when treating children. An appropriate drug dose for a 6-month-old infant may be excessive for a 1-month-old newborn but inadequate for a 5-year-old child. Other aspects of resuscitation, such as endotracheal tube size, tidal volumes, cardiac compression rates, and respiratory rates, vary with a child’s age. Equipment selection and medication dosing are based on age and body weight. Valuable time can be lost in weight estimation, dosage calculations, and equipment selection. Emergency personnel must be able to find the proper equipment rapidly. Equipment can be stored on shelves or in drawers labeled by age and weight, or a system of color codes can be used in which color-coded shelves, carts, or equipment organizers correspond to specific length categories as illustrated in Figure 109-1.

The American Heart Association Guidelines⁸ use the following age group delineations: newborn, 1 month or less in age; infant, 1 month to 1 year of age; and child, 1 year of age to the onset of puberty. As in adults, the priorities of resuscitation are airway, oxygenation, ventilation, and shock management. An important change in the 2010 American Heart Association Guidelines is the order of basic life support assessment. Instead of using ABC (airway, breathing, circulation) as a mnemonic, the American Heart Association recommends CAB, emphasizing the importance of chest compressions beginning as rapidly as possible (Figure 109-2). Reasons for this change in approach include the following: (1) starting with chest compressions reduces the delay to the start of the first compression; (2) all rescuers can start chest compressions immediately, because airway management requires manipulation and positioning of the patient; and (3) simplifying the basic life support resuscitation approach is consistent for all patients regardless of the arrest cause.^8,9 Cardiopulmonary arrest should be prevented whenever possible with prompt recognition of and intervention for compromised physiology.¹⁰ International consensus guidelines for basic life support procedures are listed in Table 109-1.^8,11

ANATOMY

A child’s airway is much smaller than an adult’s, and airway size varies by age. Anatomic and functional differences are more pronounced in infants and young children. The airway is higher and more anterior in a child’s neck than in an adult’s. The tongue and epiglottis are relatively larger, and, thus, more likely to obstruct the airway. Infants <6 months are primarily nasal breathers, so keeping the nasal passages clear is vital if spontaneous ventilation is present. Infants >6 months are able to breathe through their mouths. During CPR, ventilation by the oral route is sufficient to maintain adequate ventilation.

POSITIONING

When a child is supine, the prominent occiput causes flexion of the neck on the chest and occludes the airway. Correct airway occlusion by mild extension of the neck to the sniffing position. Overextension or hyperextension of the neck, acceptable for adults, causes obstruction and may kink the trachea, because the cartilaginous support is poor.

Maintain the sniffing position by placing a towel or other object beneath the shoulders. Despite good head position, a child’s hypotonic mandibular tissues may still allow the relatively large tongue to occlude the airway posteriorly. This condition can be relieved by a chin lift or jaw thrust that elevates the mandible anteriorly and separates the tongue from the posterior pharyngeal wall. Use the jaw thrust technique in a child with a possible cervical spine injury because it minimizes the movement of the neck and allows maintenance of a neutral position of the cervical spine. The jaw thrust may be superior to the standard chin lift and is also useful in maintaining an open airway during bag-valve mask ventilation.¹² If these maneuvers are unsuccessful, consider an oral airway device or endotracheal tube.

BASIC AIRWAY ADJUNCTS

Nasopharyngeal airways can be useful adjuncts for maintaining airway patency during resuscitation, particularly in the awake child; however, nasopharyngeal airway insertion can cause nasal trauma or bleeding due to small nasal passages and hypertrophic adenoid tissue in the posterior nasopharynx. Oral airways should be used only in unconscious children. Oral airways are most useful in children who need a continuous jaw thrust or chin lift to maintain airway patency. Oral airways are inserted with a tongue depressor to push the tongue down into the mandible so that the airway can be inserted under direct vision.

Advanced airway management in neonates and infants and the difficult pediatric airway are discussed in chapter 111.

The back blow and chest thrust are recommended maneuvers to clear an infant’s airway. The American Heart Association specifically discourages two common maneuvers used with adult patients: (1) do not use the “Heimlich maneuver” for patients <1 year old, because of the potential for injury to abdominal organs; and (2) do not use blind finger sweeps, because of the possibility of pushing the foreign body farther into the airway.^8,11

CONSCIOUS CHILDREN

A child who is choking but is able to maintain some ventilation or vocalization should be allowed to clear the airway by coughing. Once a child cannot cough, vocalize, or breathe, a sequence of steps must be instituted immediately. Choking infants are treated with an alternating sequence of five back blows and five chest thrusts.¹¹ With the infant’s torso positioned prone and head down along the rescuer’s arm, or the older child draped prone and head down across the rescuer’s knees, deliver five blows to the interscapular area. Then reposition the infant supinely along the rescuer’s arm, or place the larger infant on the floor, as for external cardiac compression, and deliver five chest thrusts (cardiac compressions) (Figures 109-3 and 109-4). Continue this sequence until the airway obstruction is relieved or the child becomes unconscious. In older children, use the obstructed airway (“Heimlich”) maneuver, with the rescuer kneeling or standing behind the child. Place the rescuer’s clenched fist at the level of the umbilicus, and deliver firm upward thrusts until the obstruction is cleared or the child becomes unconscious.

UNCONSCIOUS CHILDREN

If a child loses consciousness due to a presumed airway obstruction, begin chest compressions immediately. After 30 compressions, open the airway and look for a foreign body in the mouth. Attempt to deliver two rescue breaths. If successful, then check for a pulse. If the obstruction is still present, then continue with alternating cycles of compressions and attempted rescue breaths until the obstruction is relieved. Chest compressions will circulate blood if there is a loss of perfusion (unconsciousness) and may relieve the obstruction. After each cycle and before each attempt at ventilation (lone rescuer: 30 to 2; two rescuers: 15 to 2), inspect the airway to see if an object is present and remove visible objects. Do not perform blind finger sweeps.

The foregoing recommendations are directed primarily at first responders or healthcare providers who have neither access to nor the skills to use airway management equipment. For unconscious children in EDs, direct laryngoscopy, visualization, and removal of the foreign body with McGill forceps can be attempted. Until this equipment is ready, use basic life support techniques.

MOUTH TO MOUTH

The size of the child dictates whether to use mouth-to-mouth or mouth-to-mouth-and-nose ventilation. The rate of ventilation is shown in Table 109-1. Perform ventilations slowly to avoid the generation of high airway pressures, which can impede venous return, cause barotrauma, and result in gastric distention and regurgitation.¹¹

BAG-VALVE MASK

The self-inflating bag-valve mask system is most commonly used for ventilation. Ventilation bags used for infants and children should have a minimum volume of 450 mL, and 1000 mL for older children and adolescents.¹¹ Pediatric lung compliance is very good, and children can tolerate relatively high pressures. Pneumothoraces usually result from the administration of excessive tidal volume rather than from high pressures. The tidal volume necessary to ventilate children is the same as that for adults: 10 to 15 mL/kg. Because it is impractical to calculate the tidal volume in emergency situations, start ventilation with the smallest volume that causes adequate chest rise. Carefully monitor the rate of ventilation to avoid excessive hyperventilation.

OXYGEN

It is reasonable to provide 100% oxygen during CPR; however, once circulation has been restored, studies suggest improved outcomes when normal arterial oxygen and carbon dioxide levels are maintained. Wean oxygen to maintain saturations of >93% and assure eucapnia.^11,13,14

Monitor the brachial pulse in infants <1 year old; for older children, the femoral or carotid pulse is most easily accessible.¹¹ Begin cardiac compression in the absence of pulse or with poor perfusion (heart rate ≤60 beats/min). Perform compressions over the lower sternum, not the midsternum.⁸ The depth of compressions should be about one third of the anteroposterior chest diameter.

Place patients on a hard surface to improve the effectiveness of compressions. Palpate pulses during compression to assess the adequacy of the compression depth and rate. With bag-valve mask ventilation, pause chest compressions only long enough to deliver effective ventilations; however, once an advanced airway is established, chest compressions do not need to be paused for ventilations. See chapter 111 for further discussion.

INFANTS

Use the two-thumb technique when two healthcare providers are present. Compress at a rate of at least 100 per minute. The compression-to-ventilation ratio is 15:2 for two healthcare providers performing CPR on an infant.⁸ If the patient is intubated, then compressions and ventilations may be performed without synchronization, but the rate of compressions should be maintained at 100 per minute.

CHILDREN 1 YEAR OLD TO THE ONSET OF PUBERTY

Compress the lower half of the sternum with the heel of one hand. If unable to adequately depress the sternum with one hand, then use the two-hand technique. The rate of compression is at least 100 compressions per minute. If there are two healthcare providers, then perform compressions in a series of 15:2 compressions to ventilations. If there is only one healthcare provider, perform 30 compressions for every 2 ventilations. If the patient is intubated, then compressions and ventilations may be performed without synchronization, but keep the rate of compressions at 100 per minute.

CHILDREN AFTER PUBERTY (ADOLESCENTS)

Children who are of pubertal age or older are treated as adults with respect to basic life support.⁸ Use the two-hand technique of chest compressions. The compression-to-ventilation ratio and rate of compressions are the same as with children, 15:2 for two-person CPR and 30:2 for one-person CPR with a rate of 100 compressions per minute.

VASCULAR ACCESS

Difficulty in obtaining rapid IV access is certainly one of the major differences between adult and pediatric resuscitation. Keep several important facts in mind. First, a significant portion of children respond to airway management alone because most cardiac arrests in children are secondary to hypoxia from respiratory arrest. Do not waste time securing vascular access in children at the expense of airway management. Intraosseous infusion and fluid administration are quick, safe routes for resuscitation drugs (see chapter 112, “Intravenous and Intraosseous Access in Infants and Children”). If vascular access is needed rapidly, establish an intraosseous site until venous access is obtained. Once the child is intubated, use the tracheal route to administer drugs, such as lidocaine, epinephrine, atropine, and naloxone (mnemonic: LEAN). Although the ideal endotracheal doses for drugs other than epinephrine have never been studied in children, current recommendations support the use of two to three times the respective IV dose.^8,10

The most frequently used peripheral sites are the scalp, arm, hand, antecubital veins, and external jugular vein. If central venous access is needed, then the femoral vein is the most familiar and least complicated site. The general order of peripheral venous attempts during resuscitation should be antecubital, then hand or foot.

FLUIDS

If hypotension is due to volume depletion, give isotonic fluid boluses of 20 mL/kg as rapidly as possible and repeat as needed.¹⁰ Use a syringe attached to a three-way stopcock and extension tubing to rapidly deliver aliquots of fluid, until the entire bolus is administered. This method is far superior to the use of gravity or pressure bags.

Deliver the bolus in <20 minutes and more rapidly, if possible. Reassess the child’s condition after each bolus. If blood pressure normalizes, maintain fluid administration at the minimum rate to keep the vein open or at a rate to compensate for ongoing fluid losses. Adjust fluids and electrolytes based on calculations or laboratory results after emergency stabilization. If volume depletion is corrected with three to four fluid boluses but hypotension persists, consider a pressor agent.

Always use a pediatric microdrip assembly when resuscitating children to prevent accidental overhydration and for easy monitoring of the total volume given. It is easy to overhydrate infants and children, even when IV lines are set to keep the vein open, if adult equipment is used for children.

Proper dosage of medications in children requires knowledge of the patient’s weight, knowledge of the dose (usually given in milligrams per kg), and error-free calculation and delivery. Use a chart with precalculated drug doses to reduce dosage errors (Tables 109-2 and 109-3).