Pediatric Emergencies and Resuscitation

Published on 27/03/2015 by admin

Last modified 27/03/2015

Print this page

This article have been viewed 12115 times

Chapter 62 Pediatric Emergencies and Resuscitation

Injuries are the leading cause of death in American children and young adults and are responsible for more childhood deaths than all other causes combined (Chapter 5.1). Children are particularly vulnerable to injury for a number of reasons, including their small size, relative physical uncoordination, and limited ability to predict or understand danger. In addition, the immaturity of their developing bones, ligaments, and muscles; their thin body walls; and their relatively large heads, compared with total body surface area, make young children susceptible to serious or fatal injury from falls and collisions.

Most injuries in childhood are unintentional, and many are preventable. Motor vehicle–related injuries account for nearly half of all pediatric deaths in the USA every year, many of which are related to speeding, aggressive driving, failure to use proper passenger restraints, and/or alcohol. Consistent use of bicycle helmets could reduce the severity of head injuries, the leading cause of death when a bicyclist is struck by a car, by more than 80%. Four-sided fencing around swimming pools and use of flotation devices for every passenger in a boat could greatly reduce the risk of drowning, the second leading cause of accidental death in children younger than 5 yr and the third major cause of death in adolescents.

Serious injuries can become fatal when appropriate medical care is delayed.

Rapid, effective bystander cardiopulmonary resuscitation (CPR) for children is associated with survival rates as high as 70%, with good neurologic outcome. However, bystander CPR is still provided for less than 50% of children who experience cardiac arrest outside medical settings. This has lead to long-term survival rates of <20%, with most survivors suffering a poor neurologic outcome.

Approach to the Emergency Evaluation of a Child

The first response to a pediatric emergency of any cause is a systematic, rapid general assessment of the scene and the child to identify immediate threats to the child, care providers, or others. If an emergency is identified, the emergency response system (emergency medical services [EMS]) should be activated immediately. Care providers should then proceed through primary, secondary, and tertiary assessments as allowed by the child’s condition, safety of the scene, and resources available. This standardized approach provides organization to what might otherwise be a confusing or chaotic situation and reinforces an organized thought process for care providers. If, at any point in these assessments, the caregiver identifies a life-threatening problem, the assessment is halted and lifesaving interventions are begun. Further assessment and intervention should be delayed until other caregivers arrive or the condition is successfully treated.

General Assessment

Upon arrival at the scene of a compromised child, a caregiver’s first task is a quick survey of the scene itself. Is the rescuer or child in imminent danger because of circumstances at the scene (fire, high-voltage electricity)? If so, can the child be safely extricated to a safe location for assessment and treatment? Can the child be safely moved with the appropriate precautions (i.e., cervical spine protection), if indicated? A rescuer is expected to proceed only if these safety conditions have been met.

Once the caregiver and patient’s safety has been ensured, the caregiver performs a rapid visual survey of the child, assessing the child’s general appearance and cardiopulmonary function. This action should be very quick (only a few seconds) and should include assessment of (1) general appearance (determining color, tone, alertness, and responsiveness); (2) adequacy of breathing (distinguishing between normal, comfortable respirations and respiratory distress or apnea); and (3) adequacy of circulation (identifying cyanosis, pallor, or mottling). A child found unresponsive from an unwitnessed collapse should be approached with a gentle touch and the verbal question, “Are you OK?” If there is no response, the caregiver should immediately shout for help and send someone to both activate the emergency response system (EMS) and locate an automated external defibrillator (AED) (Fig. 62-1). The provider should then determine whether the child is breathing and, if not, provide 2 rescue breaths as described later under Recognition and Treatment of Respiratory Distress and Failure. If the child is adequately breathing, then the circulation is quickly assessed. Any child with a heart rate below 60 beats/min or without a pulse requires immediate CPR, as described under Cardiac Arrest. If the caregiver witnesses the sudden collapse of a child, the caregiver should have a higher suspicion for a sudden cardiac event. In this case, rapid deployment of an AED is of paramount importance. The provider should very briefly delay care of the child to activate EMS and locate the nearest AED.

Figure 62-1 Pediatric basic life support algorithm. AED, automated external defibrillator; ALS, advanced life support; CPR, cardiopulmonary resuscitation.

(From Berg MD, Schexnayder SM, Chameides L, et al: 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care, part 13, Circulation 122[suppl 3]:S862–S875, 2010, Fig 3, p S866.)

Primary Assessment

Once the emergency response system has been activated and the child is determined not to need CPR, the caregiver should proceed with a primary assessment that includes a brief, hands-on assessment of cardiopulmonary and neurologic function and stability. This assessment includes a limited physical exam, evaluation of vital signs, and measurement of pulse oximetry if possible. Again, a standardized approach is best. The American Heart Association, in its pediatric advanced life support (PALS) curriculum, supports the structured format of Airway, Breathing, Circulation, Disability, Exposure (ABCDE). The goal of the primary assessment is to obtain a focused, systems-based assessment of the child’s injuries or abnormalities, so that resuscitative efforts can be directed to these areas; if the caregiver identifies a life-threatening abnormality, further evaluation is postponed until appropriate corrective action has been taken.

The exam and vital sign data can be interpreted only if the caregiver has a thorough understanding of normal values. In pediatrics, normal respiratory rate, heart rate, and blood pressure have age-specific norms (Table 62-1). These ranges can be difficult to remember, especially if used infrequently. However, several standard principals apply: (1) no child’s respiratory rate should be >60 breaths/min for a sustained period; (2) normal heart rate is roughly 2-3 times normal respiratory rate for age; and (3) a simple guide for pediatric blood pressure (BP) is that the lower limit of systolic BP should be <60 mm Hg for neonates; <70 mm Hg for 1 mo–1 yr olds; <70 mm Hg + (2 × age) for 1-10 yr olds; and <90 mm Hg for any child older than 10 yr.

Table 62-1 NORMAL VITAL SIGNS ACCORDING TO AGE

Airway and Breathing

The most common precipitating event for cardiac instability in infants and children is respiratory insufficiency. Therefore, rapid assessment of respiratory failure and immediate restoration of adequate ventilation and oxygenation remain the first priority in the resuscitation of a child. Using a systematic approach, the caregiver should first assess whether the child’s airway is patent and maintainable. A healthy, patent airway is open and unobstructed, allowing normal respiration without noise or effort. A maintainable airway is one that is either already patent or can be made patent with a simple maneuver. To assess airway patency, the provider should look for breathing movements in the child’s chest and abdomen, listen for breath sounds, and feel the movement of air at the child’s mouth and nose. Abnormal breathing sounds (i.e., snoring or stridor), increased work of breathing, and apnea are all findings potentially consistent with airway obstruction. If there is evidence of airway obstruction, then maneuvers to relieve the obstruction should be instituted before the caregiver proceeds to evaluate the child’s breathing (see under Recognition and Treatment of Respiratory Distress and Failure, Initial Management).

Assessment of breathing includes evaluation of the child’s respiratory rate, respiratory effort, abnormal sounds, and pulse oximetry. Normal breathing appears comfortable, is quiet, and occurs at an age-appropriate rate. Abnormal respiratory rates include apnea and rates that are either too slow (bradypnea) or too fast (tachypnea). Bradypnea and irregular respiratory patterns require urgent attention, as they are often signs of impending respiratory failure and apnea. Signs of increased respiratory effort include nasal flaring, grunting, chest or neck muscle retractions, head bobbing, and “seesaw” respirations. Hemoglobin oxygen desaturation, as measured by pulse oximetry, often accompanies parenchymal lung disease apnea or airway obstruction. However, providers should keep in mind that adequate perfusion is required to produce a reliable oxygen saturation measurement. A child with low oxygen saturation is a child in distress. Central cyanosis is a sign of severe hypoxia and indicates an emergency need for oxygen and respiratory support.

Circulation

Cardiovascular function is assessed by evaluation of skin color and temperature, heart rate, heart rhythm, pulses, capillary refill time, and blood pressure. In nonhospital settings, much of the important information can be obtained without measuring the blood pressure; lack of blood pressure data should not prevent the provider for determining adequacy of circulation or implementing a lifesaving response. Mottling, pallor, delayed capillary refill, cyanosis, poor pulses, and cool extremities are all signs of diminished perfusion and compromised cardiac output. Tachycardia is the earliest and most reliable sign of shock, but is itself fairly nonspecific and should be correlated with other components of the exam, such as weakness, threadiness, and absence of pulses. An age-specific approach to pulse assessment will yield best results.

Disability

In the setting of a pediatric emergency, disability refers to a child’s neurologic function in terms of the level of consciousness and cortical function. Standard evaluation of a child’s neurologic condition can be done quickly with an assessment of pupillary response to light (if one is available) and use of either of the standard scores used in pediatrics: the Alert, Verbal, Pain, Unresponsive (AVPU) Pediatric Response Scale and the Glasgow Coma Scale (GCS) (Tables 62-2 and 62-3). The causes of decreased level of consciousness in children are numerous and include conditions as diverse as respiratory failure with hypoxia or hypercarbia, hypoglycemia, poisonings or drug overdose, trauma, seizures, infection, and shock. Most commonly, an ill or injured child has an altered level of consciousness because of respiratory compromise, circulatory compromise, or both. Any child with a depressed level of consciousness should be immediately assessed for abnormalities in cardiorespiratory status.

Table 62-2 AVPU NEUROLOGIC ASSESSMENT

A	The child is awake, alert, and interactive with parents and care providers
V	The child responds only if the care provider or parents call the child’s name or speak loudly
P	The child responds only to painful stimuli, such as pinching the nail bed of a toe or finger
U	The child is unresponsive to all stimuli

From Ralston M, Hazinski MF, Zaritsky AL, et al, editors: Pediatric advanced life support course guide and PALS provider manual: provider manual, Dallas, 2007, American Heart Association.

Table 62-3 GLASGOW COMA SCALE

Secondary Assessment

For care providers in community or outpatient settings, transfer of care of a child to emergency or hospital personnel may occur before a full secondary assessment is possible. However, before the child is removed from the scene and separated from witnesses or family, a brief history should be obtained for medical providers at the accepting facility. The components of a secondary assessment include a focused history and focused physical exam.

The history should be targeted to information that could explain cardiorespiratory or neurologic dysfunction and should take the form of a SAMPLE history (Signs/symptoms, Allergies, Medications, Past medical history, timing of Last meal, and Events leading to this situation). Medical personnel not engaged in resuscitative efforts can be dispatched to elicit history from witnesses or relatives. The physical exam during the secondary assessment is a thorough head-to-toe exam, although the severity of the child’s illness or injury could necessitate curtailing portions of the exam or postponing nonessential elements until a later time.

Tertiary Assessment

The tertiary assessment occurs in a hospital setting, where ancillary laboratory and radiographic assessments contribute to a thorough understanding of the child’s condition. A basic blood chemistry profile, complete blood count, liver function tests, coagulation studies, and arterial blood gas analyses give fairly broad (but somewhat nonspecific) estimates of renal function, acid-base balance, cardiorespiratory function, and presence or absence of shock. Chest radiographs can be useful to evaluate both the heart and lungs, although more detailed estimates of heart function and cardiac output can be made with echocardiography. Arterial and central venous catheters can be placed to monitor arterial and central venous pressure (see under Vascular Access).

Recognition and Treatment of Respiratory Distress and Failure

The goals of initial management of respiratory distress or failure are to rapidly stabilize the child’s airway and breathing and to identify the cause of the problem so that further therapeutic efforts can be appropriately directed.

Airway Obstruction

Children <5 yr old are particularly susceptible to foreign body aspiration and choking. Liquids are the most common cause of choking in infants, whereas small objects and food (e.g., grapes, nuts, hot dogs, candies) are the most common source of foreign bodies in the airways of toddlers and older children. A history consistent with foreign body aspiration is considered diagnostic. Any child in the proper setting with the sudden onset of choking, stridor, or wheezing has foreign body aspiration until proven otherwise.

Airway obstruction is treated with a sequential approach, starting with the head-tilt/chin-lift maneuver to open and support the airway, followed by inspection for a foreign body, and finger-sweep clearance or suctioning if one is visualized (Fig. 62-2). Blind suctioning or finger sweeps of the mouth are not recommended. A nasopharyngeal airway (NPA) or oropharyngeal airway (OPA) can be inserted for airway support, if indicated. A conscious child suspected of having a partial foreign body obstruction should be permitted to cough spontaneously until coughing is no longer effective, respiratory distress and stridor increase, or the child becomes unconscious.

Figure 62-2 Opening the airway with the head-tilt/chin-lift maneuver. One hand is used to tilt the head, extending the neck. The index finger of the rescuer’s other hand lifts the mandible outward by lifting the chin. Head-tilt should not be performed if a cervical spine injury is suspected.

(From Guidelines for cardiopulmonary resuscitation and emergency cardiac care. Emergency Cardiac Care Committee and Subcommittees, American Heart Association. Part V. Pediatric basic life support, JAMA 268:2251–2261, 1992.)

If the child becomes unconscious, the child should be gently placed on the ground, supine. The provider should then open the airway with the head-tilt/chin-lift maneuver and attempt mouth-to-mouth ventilation (Figs. 62-3 and 62-4). If ventilation is unsuccessful, the airway is repositioned, and ventilation attempted again. If there is still no chest rise, attempts to remove a foreign body are indicated. In an infant <1 yr old, a combination of 5 back blows and 5 chest thrusts is administered (Fig. 62-5). After each cycle of back blows and chest thrusts, the child’s mouth should be visually inspected for the presence of the foreign body. If identified within finger’s reach, it should be removed with a gentle finger sweep. If no foreign body is visualized, ventilation is again attempted. If this is unsuccessful, the head is repositioned, and ventilation attempted again. If there is no chest rise, the series of back blows and chest thrusts is repeated.

Figure 62-3 Rescue breathing in an infant. The rescuer’s mouth covers the infant’s nose and mouth, creating a seal. One hand performs the head-tilt while the other hand lifts the infant’s jaw. Avoid head-tilt if the infant has sustained head or neck trauma.

Figure 62-4 Rescue breathing in a child. The rescuer’s mouth covers the child’s mouth, creating a mouth-to-mouth seal. One hand maintains the head-tilt; the thumb and forefinger of the same hand are used to pinch the child’s nose.

Figure 62-5 Back blows (top) and chest thrusts (bottom) to relieve foreign body airway obstruction in the infant.

For a conscious child >1 yr old, providers should give a series of 5 abdominal thrusts (Heimlich maneuver) with the child standing or sitting (Fig. 62-6); this should occur with the child lying down if unconscious (Fig. 62-7). After the abdominal thrusts, the airway is examined for a foreign body, which should be removed if visualized. If no foreign body is seen, the head is repositioned, and ventilation attempted. If it is unsuccessful, the head is repositioned and ventilation is attempted again. If these efforts are unsuccessful, the Heimlich sequence is repeated.

Figure 62-6 Abdominal thrusts with the victim standing or sitting (conscious).

Figure 62-7 Abdominal thrusts with victim lying (conscious or unconscious).

Airway Narrowing

Airway obstruction can also be caused by airway narrowing, in both the upper and lower airways. Upper airway obstruction refers to narrowing of the extrathoracic portion of the airway, including the oropharynx, larynx, and trachea. In the upper airways, narrowing is most often caused by airway edema (croup or anaphylaxis). Lower airway disease affects all intrathoracic airways, notably the bronchi and bronchioles. In the lower airways, bronchiolitis and acute asthma exacerbations are the major contributors to intrathoracic airway obstruction in children, causing airway narrowing through a combination of airway swelling, mucus production, and circumferential smooth muscle constriction of smaller airways.

Airway support for these processes is dictated by both the underlying condition and the clinical severity of the problem. In cases of mild upper airway obstruction, the child has minimally elevated work of breathing (evidenced by tachypnea and few to mild retractions). Stridor, if present at all, should be audible with only coughing or activity. Children with these findings can be supported with nebulized cool mist and supplemental oxygen as needed. In cases with moderate obstruction, in which the child has a higher work of breathing and more pronounced stridor, nebulized racemic epinephrine and oral or intravenous (IV) dexamethasone can be added. Children with severe upper airway obstruction have marked retractions, prominent stridor, and decreased air entry on auscultation of the lung fields. Most children with significant airway obstruction are also hypoxic, and many appear dyspneic and agitated. A child in severe distress needs to be closely observed, as the signs of impending respiratory failure may be initially confused with improvement. Stridor becomes quieter and retractions less prominent when a child’s respiratory effort begins to diminish. The child in respiratory failure can be distinguished from one who is improving by evidence of poor air movement on auscultation and lethargy or decreased level of consciousness from hypercarbia, hypoxia, or both. When anaphylaxis is suspected as the cause for upper airway edema, providers should administer an intramuscular (IM) or IV dose of epinephrine as needed (Chapter 143). No matter the cause, any child in impending respiratory failure should be prepared for endotracheal intubation and respiratory support.

In cases of lower airway obstruction, therapies are targeted to both relieving the obstruction and reducing the child’s work of breathing. Inhaled bronchodilators, such as albuterol, augmented by oral or IV corticosteroids, remain the mainstay of therapy in settings of mild to moderate acute distress due to lower airway obstruction. Children with more significant obstruction appear dyspneic, with tachypnea, retractions, and easily audible wheezing. In these cases, the addition of an anticholinergic agent, such as nebulized ipratropium bromide, or a smooth muscle relaxant, such as magnesium sulfate, may provide further relief, although the evidence for these measures remains controversial (Chapter 138). Supplemental oxygen and IV fluid hydration can also be useful adjuncts. As in cases of upper airway obstruction, impending respiratory failure in children with lower airway obstruction can be insidious. When diagnosed early in a school-aged child who is cooperative, respiratory failure can be averted through judicious use of noninvasive support, with continuous positive airway pressure (CPAP), bilevel positive airway pressure (BiPAP), or heliox (combined helium-oxygen therapy). Endotracheal intubation should be performed only by skilled providers, preferably in a hospital setting, because there is a high risk of respiratory and circulatory compromise in patients with lower airway obstruction during the procedure.

Parenchymal Lung Disease

Parenchymal lung disease includes a heterogeneous list of conditions, such as pneumonia, acute respiratory distress syndrome, pneumonitis, bronchopulmonary dysplasia, cystic fibrosis, and pulmonary edema. The commonalities of these conditions are their effects on the alveoli, including inflammation and exudation leading to consolidation of lung tissue, decreased gas exchange, and increased work of breathing. Clinical management of these conditions includes specific treatment as indicated (i.e., antibiotics for bacterial pneumonia) and supportive care in the form of supplemental oxygen, noninvasive respiratory support (with CPAP or BiPAP), or invasive mechanical ventilation.

Advanced Airway Management Techniques

Bag-Valve-Mask Positive Pressure Ventilation

Rescue breathing with a bag-valve-mask apparatus can be as effective as endotracheal intubation and safer when the provider is inexperienced with intubation. Bag-valve-mask ventilation itself requires training to ensure that the provider is competent to select the correct mask size, open the child’s airway, form a tight seal between the mask and the child’s face, deliver effective ventilation, and assess the effectiveness of the ventilation. An appropriately sized mask is one that fits over the child’s mouth and nose but does not extend below the chin or over the eyes (Fig. 62-8). An adequate seal is best achieved via a combination “C–E” grip on the mask, in which the thumb and index finger form the letter “C” on top of the mask, pressing the mask downward onto the child’s face, and the remaining three fingers form an “E” grip under the child’s mandible, holding the jaw forward and extending the head up toward the mask. Using this method, the care provider can secure the mask to the child’s face with one hand and use the other hand to compress the ventilation bag (Fig. 62-9).

Figure 62-8 Appropriate sizing technique for pediatric bag-valve-mask apparatus.

(From American Academy of Pediatrics and the American Heart Association; Short J, editor: Textbook of neonatal resuscitation, ed 5, Elk Grove, IL, American Academy of Pediatrics, 2006, pp 3–16.)