Pediatric Emergencies and Resuscitation

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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.)

Figure 62-9 “C–E” grip to secure bag-valve-mask to a child’s face with appropriate seal.

The provider may have to move the head and neck through a range of positions to find the one that best maintains airway patency and allows maximal ventilation. In infants and young children, optimal ventilation is often provided when the child’s head is in the neutral “sniffing” position without hyperextension of the head (Fig. 62-10). Poor chest rise and persistently low oxygen saturation values indicate inadequate ventilation. In this setting, the care provider should recheck the mask’s seal on the child’s face, reposition the child’s head, and consider suctioning the airway if indicated. If these maneuvers do not restore ventilation, then the provider should consider endotracheal intubation.

Figure 62-10 Appropriate head position for bag-valve-mask ventilation.

(From American Academy of Pediatrics and the American Heart Association; Short J, editor: Textbook of neonatal resuscitation, ed 5, Elk Grove, IL, 2006, American Academy of Pediatrics, pp 3–18.)

Endotracheal Intubation

A child requires intubation when at least one of these conditions exists: (1) the child is unable to maintain airway patency or protect the airway against aspiration (as occurs in settings of neurologic compromise), (2) the child is failing to maintain adequate oxygenation, (3) the child is failing to control blood carbon dioxide levels and maintain safe acid-base balance, (4) sedation and/or paralysis is required for a procedure, and (5) care providers anticipate a deteriorating course that will eventually lead to the first 4 conditions. There are few absolute contraindications to tracheal intubation, but experts generally agree that in settings of known complete airway obstruction, endotracheal intubation should be avoided, and emergency cricothyroidotomy performed instead. Another important consideration is to ensure that caregivers provide appropriate cervical spine protection during the intubation procedure when neck or spinal cord injury is suspected.

The most important phase of the intubation procedure is the preprocedure preparation, when the provider ensures all the equipment and staff needed for safe intubation are present and functioning. An easy pneumonic for this is SOAP MM: suction (Yankauer suction catheter attached to wall suction); oxygen (both preoxygenation of the patient and devices needed to deliver oxygen, such as a bag-valve-mask device); airway (appropriately sized endotracheal tube and laryngoscope); people (all those needed during and immediately after the procedure, such as respiratory therapists and nurses); monitor (to monitor the child’s oxygen saturation, heart rate, and blood pressure); and medications (to sedate the child and allow the provider to control the airway). A simple formula for selecting the appropriately sized ET tube is as follows:

Analgesia is recommended to reduce metabolic stress, discomfort, and anxiety during intubation. Pretreatment with a sedative, an analgesic, and possibly a muscle relaxant is recommended unless the situation is an emergency (i.e., apnea, asystole, unresponsiveness) and the administration of drugs would cause an unacceptable delay.

Because many intubations in critically ill children are emergency procedures, caregivers should be prepared for rapid sequence intubation (RSI) (Fig. 62-11; Table 62-4). The goals of RSI are to induce anesthesia and paralysis and to complete intubation quickly. This approach minimizes elevations of intracranial pressure and blood pressure that may accompany intubation in awake or lightly sedated patients. Because the stomach generally cannot be emptied before RSI, the Sellick maneuver (downward pressure on the cricoid cartilage to compress the esophagus against the vertebral column) should be used to prevent aspiration of gastric contents.

Figure 62-11 A-E, Intubation technique.

(From Fleisher G, Ludwig S: Textbook of pediatric emergency medicine. Baltimore, 1983, Williams & Wilkins, p 1250.)

Table 62-4 RAPID SEQUENCE INTUBATION

STEP	PROCEDURE	COMMENT/EXPLANATION
1	Obtain a brief history and perform an assessment	Rule out drug allergies; examine the airway anatomy (e.g., micrognathia, cleft palate)
2	Assemble equipment, medications, etc.	See lists below
3	Preoxygenate the patient	With bag/mask, nasal cannula, hood or blow-by
4	Premedicate the patient with lidocaine, atropine	Lidocaine minimizes the ICP rise with intubation and can be applied topically to the airway mucosa for local anesthesia
4	Premedicate the patient with lidocaine, atropine	Atropine helps blunt the bradycardia associated with upper airway manipulation and reduces airway secretions
5	Induce sedation and analgesia	Sedatives:
		Thiopental (2-5 mg/kg): Very rapid onset; can cause hypotension.
		Diazepam (0.1 mg/kg): Onset 2-5 min; elimination in 30-60 min or more.
		Ketamine (2 mg/kg): Onset 1-2 min; elimination in 30-40 min. May cause hallucinations if used alone; causes higher ICP, mucous secretions, increased vital signs, and bronchodilation.
		Analgesics:
		Fentanyl (3-10 µg/kg, may repeat 3-4×): Rapid administration risks “tight chest” response, with no effective ventilation. Effects wear off in 20-30 min.
		Morphine (0.05-0.1 mg/kg dose): May last 30-60 min; may lead to hypotension in hypovolemic patients.
6	Pretreat with nondepolarizing paralytic agent	Small dose of a nondepolarizing paralytic agent (see below), with intent of diminishing the depolarizing effect of succinylcholine, which is administered next
7	Administer muscle relaxants	Succinylcholine dose is 1-2 mg/kg; causes initial contraction of muscles, then relaxation. This depolarization can, however, raise ICP and blood pressure. Onset of paralysis in 30-40 sec; duration is 5-10 min.
7	Administer muscle relaxants	Increased use of pretreatment with a nondepolarizing muscle relaxant, especially rocuronium (1 mg/kg), which has a very rapid onset and short duration. Other nondepolarizing agents include vecuronium and pancuronium, both dosed at 0.1 mg/kg.
8	Perform a Sellick maneuver	Pressure on the cricoid cartilage, to occlude the esophagus and prevent regurgitation or aspiration
9	Perform endotracheal intubation	ET: Select the proper size for the age and weight of the child
		Laryngoscope blades: A variety of Miller and the Macintosh blades
		Patient supine; the neck is extended moderately to the “sniffing” position
10	Secure the tube and verify the position with a roentgenogram	ET secured with tape to the cheeks and upper lip or to an adhesive patch applied to the skin near the mouth.
11	Begin mechanical ventilation	Verify tube placement before ventilating with positive pressure; if an ET tube is in one bronchus, barotraumas may occur

ET, endotracheal tube; ICP, intracranial pressure.

Once the patient is intubated, proper tube placement should be assessed by auscultation of breath sounds, evidence of symmetric chest rise, and analysis of exhaled carbon dioxide (CO₂) by a colorimetric device placed within the respiratory tubing near the endotracheal tube or a device that directly measures carbon dioxide elimination (i.e., capnogram or capnograph). Chest radiography is necessary to confirm appropriate tube position.

Recognition and Management of Shock

In simple terms, shock occurs when oxygen and nutrient delivery to the tissues is inadequate to meet metabolic demands (Chapter 64). The definition of shock does not include hypotension, and it is important for care providers to understand that shock does not begin when blood pressure drops but merely worsens and becomes more difficult to treat once blood pressure is abnormal.

Early compensated shock, whereby oxygen delivery is mostly preserved through compensatory mechanisms, is defined by the presence of normal blood pressure. When compensatory mechanisms fail, the shock progresses to decompensated shock, which is defined by hypotension and organ dysfunction. In irreversible shock, organ failure progresses and death ensues.

Shock is also often described according to the underlying pathophysiology, which dictates the appropriate therapeutic response. Hypovolemic shock is the most common type of shock in children worldwide, usually related to fluid losses from severe diarrhea. Hemorrhage is a cause of hypovolemic shock after trauma or intestinal hemorrhage. When hypovolemia occurs as a result of third spacing of intravascular fluids into the extravascular compartment, the shock is described as distributive shock. The most common causes of distributive shock are sepsis and burn injuries, in which release of inflammatory cytokines causes massive capillary leak of fluid and proteins, leading to low oncotic pressure and intravascular volume. In settings of profound myocardial dysfunction, a child has tissue hypoperfusion from cardiogenic shock. The most common causes of cardiogenic shock are congenital heart disease, myocarditis, and cardiomyopathies. Obstructive shock occurs when cardiac output is lowered by obstruction of blood flow to the body, as occurs when a ductus arteriosus closes in a child with ductus-dependent systemic blood flow in pericardial tamponade, tension pneumothorax, or massive pulmonary embolism.

The evaluation of a child in shock should proceed as described in the preceding sections on primary, secondary, and tertiary assessments. If the child presents in a hospital setting, providers should obtain central venous and arterial access to permit a more thorough laboratory assessment of all organ systems, including studies of renal and liver function, acid-base balance and presence of lactic acidosis, hypoxemia and/or hypercapnia, and evidence of coagulopathy or disseminated intravascular coagulation (DIC). Chest radiography and more sophisticated assessments, such as echocardiography, may also be useful. Respiratory and cardiovascular support should be provided as indicated.

The treatment of shock focuses on the modifiable determinants of oxygen delivery while reducing the imbalance between oxygen demand and supply. A multipronged approach is recommended; it consists of optimizing the oxygen content of the blood, improving the volume and distribution of cardiac output, correcting metabolic derangements, and reducing oxygen demand. Blood oxygen content is maximized when hemoglobin values are normal and 100% of available hemoglobin is saturated with oxygen. Transfusion should be considered in the presence of hemorrhagic or distributive shock, in which crystalloid volume resuscitation has led to hemodilution and anemia. High oxygen saturations may be achieved by simple maneuvers such as oxygen administration via nasal cannula or face mask, but supportive measures that provide positive pressure, such as CPAP, BiPAP, or even mechanical ventilation, may be necessary. Therapies to increase cardiac output should be selected on the basis of underlying pathophysiology. For hypovolemic and distributive shock, aggressive volume resuscitation, guided by arterial and central venous pressures, is the mainstay of therapy. In obstructive shock, relief of the obstruction is critical. The ductus arteriosus can often be reopened with prostaglandin administration, and tamponade physiology can be relieved with appropriate drain placement, as described under Nonvascular Emergency Procedures.

Recognition of Bradyarrhythmias and Tachyarrhythmias

In the advanced life support setting, arrhythmias are most usefully classified according to the observed heart rate (slow or fast) and its effect on perfusion (adequate or poor). If, in the primary survey, a caregiver finds a child with an abnormal heart rate plus poor perfusion and/or altered mental status, then the rhythm is inadequate no matter its rate. In those settings, the child is diagnosed with shock, and further evaluation is halted until appropriate resuscitation has been initiated.

Bradyarrhythmias

By definition, a child is bradycardic when the heart rate is slower than the normal range for age (see Table 62-1). Sinus bradycardia can be a harmless incidental finding in an otherwise healthy person and is not commonly associated with cardiac compromise. A relative bradycardia occurs when the heart rate is too slow for a child’s activity level or metabolic needs. A clinically significant bradycardia occurs when the heart rate is slow and there are signs of systemic hypoperfusion (i.e., pallor, altered mental status, hypotension, acidosis). Symptomatic bradycardia occurs most often in the setting of hypoxia but can also be caused by hypoglycemia, hypocalcemia, other electrolyte abnormalities, and intracranial hypertension. Bradyarrhythmias are often the most common pre-arrest rhythms in young children.

Initial management of symptomatic bradycardia includes support or opening of the airway and confirming or establishing adequate oxygenation and ventilation (Fig. 62-12). After the child’s breathing has been secured, the child should be reassessed for continued bradycardia and poor perfusion—if cardiac compromise was solely the result of respiratory insufficiency, support of the child’s airway and breathing may have been sufficient to restore normal hemodynamics. If respiratory support does not correct the perfusion abnormalities, then further care is based on the quality of perfusion and the degree of bradycardia. A heart rate less than 60 beats/min with poor perfusion is an indication to begin chest compressions. If the child’s heart rate is above 60 beats/min, vascular access should be obtained; resuscitative epinephrine should be administered, and it should be repeated every 3-5 min for persistent symptomatic bradycardia. If increased vagal tone (e.g., in the setting of head injury with raised intracranial pressure) or primary atrioventricular block is suspected, atropine can also be given. For cases of refractory bradycardia, cardiac pacing should be considered. During the resuscitation of a child with bradycardia, providers should assess and treat factors known to cause bradycardia, referred to collectively as the 6 Hs (hypoxia, hypovolemia, hydrogen ions [acidosis], hypokalemia or hyperkalemia, hypoglycemia, hypothermia), and 4 Ts (toxins, tamponade, tension pneumothorax, and trauma [causing hypovolemia, intracranial hypertension, cardiac compromise or tamponade]) (Table 62-5).

Figure 62-12 Pediatric advanced life support bradycardia algorithm. ABCs, airway, breathing, and circulation; AV, atrioventricular (conductor); ECG, electrocardiogram; HR, heart rate.

(From Kleinman ME, Chameides L, Schexnayder SM, et al: 2010 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care, part 14, Circulation 122 [suppl 3]:S876–S908, 2010, Fig 2, p S887.)

Table 62-5 POTENTIALLY TREATABLE CONDITIONS ASSOCIATED WITH CARDIAC ARREST

CONDITION	COMMON CLINICAL SETTINGS	CORRECTIVE ACTIONS
Acidosis	Pre-existing acidosis, diabetes, diarrhea, drugs and toxins, prolonged resuscitation, renal disease, and shock	Reassess the adequacy of cardiopulmonary resuscitation, oxygenation, and ventilation; reconfirm endotracheal tube placement Hyperventilate Consider intravenous bicarbonate if pH <7.20 after above actions have been taken

Cardiac tamponade Hemorrhagic diathesis, cancer, pericarditis, trauma, after cardiac surgery, and after myocardial infarction

Administer fluids; obtain bedside echocardiogram, if available

Perform pericardiocentesis; immediate surgical intervention is appropriate if pericardiocentesis is unhelpful but cardiac tamponade is known or highly suspected

Hypothermia Alcohol abuse, burns, central nervous system disease, debilitated patient, drowning, drugs and toxins, endocrine disease, history of exposure, homelessness, extensive skin disease, spinal cord disease, and trauma

If hypothermia is severe (temperature <30°C), limit initial shocks for ventricular fibrillation or pulseless ventricular tachycardia to 3; initiate active internal rewarming and cardiopulmonary support; hold further resuscitation medications or shocks until core temperature is >30°C

If hypothermia is moderate (temperature 30-34°C), proceed with resuscitation (space medications at longer intervals than usual), passively rewarm child, and actively rewarm truncal body areas

Hypovolemia, hemorrhage, anemia Major burns, diabetes, gastrointestinal losses, hemorrhage, hemorrhagic diathesis, cancer, pregnancy, shock, and trauma

Administer fluids

Transfuse packed red blood cells if hemorrhage or profound anemia is present

Thoracotomy is appropriate when a patient has cardiac arrest from penetrating trauma and a cardiac rhythm and the duration of cardiopulmonary resuscitation before thoracotomy is <10 min

Hypoxia Consider in all patients with cardiac arrest Reassess the technical quality of cardiopulmonary resuscitation, oxygenation, and ventilation; reconfirm endotracheal tube placement Hypomagnesemia Alcohol abuse, burns, diabetic ketoacidosis, severe diarrhea, diuretics, and drugs (e.g., cisplatin, cyclosporine, pentamidine) Administer 1-2 g magnesium sulfate IV over 2 min Poisoning Alcohol abuse, bizarre or puzzling behavioral or metabolic presentation, classic toxicologic syndrome, occupational or industrial exposure, and psychiatric disease

Consult a toxicologist for emergency advice on resuscitation and definitive care, including an appropriate antidote

Prolonged resuscitation efforts may be appropriate; immediate cardiopulmonary bypass should be considered, if available

Hyperkalemia Metabolic acidosis, excessive administration of potassium, drugs and toxins, vigorous exercise, hemolysis, renal disease, rhabdomyolysis, tumor lysis syndrome, and clinically significant tissue injury If hyperkalemia is identified or strongly suspected, treat* with all of the following: 10% calcium chloride (5-10 mL by slow IV push; do not use if hyperkalemia is secondary to digitalis poisoning), glucose and insulin (50 mL of 50% dextrose in water and 10 units of regular insulin IV), sodium bicarbonate (50 mmol IV; most effective if concomitant metabolic acidosis is present), and albuterol (15-20 mg nebulized or 0.5 mg by IV infusion) Hypokalemia Alcohol abuse, diabetes, use of diuretics, drugs and toxins, profound gastrointestinal losses, hypomagnesemia If profound hypokalemia (<2-2.5 mmol of potassium V) is accompanied by cardiac arrest, initiate urgent IV replacement (2 mmol/min IV for 10-15 mmol)*; then reassess Pulmonary embolism Hospitalized patient, recent surgical procedure, peripartum, known risk factors for venous thromboembolism, history of venous thromboembolism, or pre-arrest presentation consistent with a diagnosis of acute pulmonary embolism

Administer fluids; augment with vasopressors as necessary

Confirm the diagnosis, if possible; consider immediate cardiopulmonary bypass to maintain patient’s viability

Consider definitive care (e.g., thrombolytic therapy, embolectomy by interventional radiology or surgery)

Tension pneumothorax Placement of a central catheter, mechanical ventilation, pulmonary disease (including asthma, chronic obstructive pulmonary disease, and necrotizing pneumonia), thoracentesis, and trauma Needle decompression, followed by chest tube insertion

IV, intravenously.

* Adult dose. Adjust for size of child. See Table 62-6.

From Eisenbery MS, Mengert TJ: Cardiac resuscitation, N Engl J Med 344:1304–1313, 2001.

Tachyarrhythmias

Tachyarrhythmias represent a variety of rhythm disturbances of both atrial and ventricular origin. Sinus tachycardia is a normal physiologic response to the body’s need for increased cardiac output or oxygen delivery, as occurs with fever, exercise, or stress. It can also occur in more pathologic states, such as hypovolemia, anemia, pain, anxiety, and metabolic stress. Tachyarrhythmias that do not originate in the sinus node are often categorized as narrow complex rhythms (those originating in the atrium, such as atrial flutter or supraventricular tachycardia [SVT]) and wide complex rhythms (those rhythms of ventricular origin, such as ventricular tachycardia).

As in the bradycardia algorithm, the initial management of tachycardia includes confirmation that the child has an adequate airway and life-sustaining breathing and circulation (Fig. 62-13). For children with persistent symptoms, further treatment is based on whether the QRS complex of the electrocardiogram (ECG) is narrow (≤0.08 sec) or wide (>0.08 sec). For narrow complex tachycardia, providers must distinguish between sinus tachycardia and SVT. In sinus tachycardia, (1) the history and onset are consistent with a known cause of tachycardia, such as fever or dehydration and (2) P waves are consistently present, are of normal morphology, and occur at a rate that varies somewhat. In SVT, (1) onset is often abrupt without prodrome and (2) P waves are absent or polymorphic, and when present, their rate is often fairly steady at or above 220 beats/min. For children with SVT and good perfusion, vagal maneuvers can be attempted. In cases in which SVT is associated with poor perfusion, providers should rapidly move to convert the child’s heart rhythm back to sinus rhythm. If the child already has IV access, then adenosine can be given via IV with rapid “push.” Adenosine has an extremely short half-life, so a proximal IV is best, and the adenosine should be set up with a three-way stopcock so it can be given and immediately flushed into the circulation. If the child does not have IV access, or adenosine does not successfully convert the heart rhythm back to sinus rhythm, then synchronized cardioversion, using 0.5-1 joule/kg, should be performed. In cases of wide complex tachycardia, providers should move immediately to cardioversion and increase the dose to 2 joules/kg if 1 joule/kg is not effective. As with cases of bradycardia, providers should review the 6 Hs and 4 Ts to identify factors that might be contributing to the tachycardia (see Table 62-5).

Figure 62-13 Pediatric advanced life support tachycardia algorithm. AV, atrioventricular (conductor); ECG, electrocardiogram; HR, heart rate.

Recognition and Management of Cardiac Arrest

Cardiac arrest occurs when the heart fails as an effective pump and blood flow ceases. Outwardly, the patient in cardiac arrest presents as unresponsive and apneic with no palpable pulse. Internally, the cessation of nutrient flow causes progressive tissue ischemia and organ dysfunction. If not rapidly reversed, cardiac arrest leads to progressive deterioration in brain and heart function such that resuscitation and recovery are no longer possible.

Pediatric cardiac arrest is rarely the cause of a sudden coronary event or arrhythmia. Instead, cardiac arrest in children is most often the end result of progressive asphyxia, caused by tissue hypoxia, acidosis, and nutrient depletion at the end stages of respiratory deterioration, shock, or heart failure. Therefore, the most important treatment of cardiac arrest is anticipation and preventive: Intervening when a child manifests respiratory distress or early stages of shock can prevent deterioration to full-blown arrest. When sudden cardiac arrest does occur, it is most often associated with an arrhythmia, specifically ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). In sudden events such as these, the key to successful resuscitation is early recognition of the arrhythmia and prompt treatment with high-quality CPR and defibrillation.

The principle behind high-quality CPR is that adequate chest compressions—those that circulate blood around the body with a good pulse pressure—are the most important component of CPR. The caregiver providing chest compressions should push hard, push fast, allow for complete chest recoil, and minimize interruptions. Ideally, chest compressions should be interrupted only for ventilation, a rhythm check, or delivery of a defibrillating shock.

Cardiac arrest is recognized from general and primary survey findings consistent with a pale or cyanotic child who is unresponsive, apneic, and pulseless. Even experienced providers have a relatively high error rate when asked to determine presence or absence of pulse in a child. Therefore, any child found unresponsive and apneic can be presumed to be in cardiac arrest, and a rescuer should respond accordingly. A lone rescuer for an unwitnessed pediatric cardiac arrest in an outpatient setting should treat the arrest as asphyxial in nature and should immediately initiate CPR. The rescuer should perform initial rescue breaths and 2 min of chest compressions and ventilations before leaving the child to activate the emergency response system. For an in-hospital arrest, the provider should call for help and send someone else to activate the emergency response system while beginning CPR. A lone rescuer in an outpatient setting who witnesses a child suddenly collapse should treat the arrest as a primary arrhythmia, should immediately activate the EMS system, and should obtain an AED. Upon returning to the child, the rescuer should confirm pulselessness, turn on the AED, place the leads on the child’s chest, and follow the defibrillator’s voice commands.

The initial step in CPR for a child of any age is to restore ventilation and oxygenation as quickly as possible. Upon confirmation of unresponsiveness, apnea, and pulselessness, the provider should open the airway with a head-tilt/chin-lift maneuver (or jaw-thrust if cervical spine trauma is suspected) and provide 2 initial rescue breaths (Fig. 62-14). These breaths are deep and slow, lasting approximately 1 sec per breath. The breaths are adequate if they cause the chest to rise and fall and improve the child’s color. If the breaths appear inadequate, the child should be repositioned, and the breaths delivered again. If the breaths remain ineffective, the provider should assess the child for foreign body aspiration. After 2 effective rescue breaths, the child’s pulse should be assessed. If the child has a pulse but remains apneic (or with ineffective breathing), then the rescuer should continue to provide assisted ventilation at an age-appropriate rate. Infants and children ≤8 yr old should receive rescue breathing at a rate of roughly 15-20 breaths/min, or roughly 1 breath every 3-5 sec. Children >8 yr old should receive 10-12 breaths/min, or 1 breath every 5-6 sec.

Figure 62-14 Combined jaw-thrust/spine stabilization maneuver for the pediatric trauma victim.

If the child remains pulseless, chest compressions should be initiated. Chest compressions in infants <1 yr old may be performed by placing 2 thumbs on the midsternum with the hands encircling the thorax or by placing 2 fingers over the midsternum and compressing (Figs. 62-15 and 62-16). For children >1 yr old, the care provider should perform chest compressions over the lower half of the sternum with the heel of 1 hand, or with 2 hands as used for adult resuscitation (Fig. 62-17). In all cases, care should be taken to avoid compression of the xiphoid and the ribs. When feasible, a cardiac resuscitation board should be placed under the child’s back to maximize the efficiency of compressions. When a lone rescuer provides CPR, the universal ratio of 30 compressions to 2 ventilations is used. Pediatric patients in cardiac arrest are thought to have the best chance of survival if more frequent ventilation is offered. Therefore, the ratio should be lowered to 15 compressions to 2 ventilations for children ≤8 yr old as soon as a second care provider is available. In the outpatient setting, resuscitation effort should pause periodically to allow the provider to make an assessment of the possible return of spontaneous heart rate, pulse, and respirations. The goal of CPR is to re-establish spontaneous circulation at a level that is compatible with survival. If resuscitative efforts do not succeed in re-establishing life-sustaining breathing and circulation, the medical team must decide whether continued efforts are warranted or whether the resuscitation should be stopped. If EMS care is en route, bringing the potential for further escalation in care such as endotracheal intubation, vascular access, and medications, CPR should be continued as long as possible or deemed reasonable by the rescuers.

Figure 62-15 Cardiac compressions. Top, The infant is supine on the palm of the rescuer’s hand. Bottom, Performing CPR while carrying an infant or small child. Note that the head is kept level with the torso.

Figure 62-16 Thumb method of chest compressions. A, Infant receiving chest compressions with thumb 1 fingerbreadth below the nipple line and hands encircling chest. B, Hand position for chest encirclement technique for external chest compressions in neonates. Thumbs are side by side over the lower third of the sternum. In the small newborn, thumbs may need to be superimposed (inset). Gloves should be worn during resuscitation.

(From Fleisher GR, Ludwig S, editors: Textbook of pediatric emergency medicine, Philadelphia, 2010, Wolters Kluwer/Lippincott Williams & Wilkins Health, Fig. 2.2.)

Figure 62-17 Locating the hand position for chest compression in a child. Note that the rescuer’s other hand is used to maintain the head position to facilitate ventilation.

In the in-hospital setting, the ECG should dictate further resuscitative efforts. For children without a pulse and in asystole or electromechanical dissociation (pulseless electrical activity [PEA]), providers should continue rescue breathing and CPR, obtain vascular access, and give emergency IV epinephrine (Fig. 62-18). For continued asystole or PEA, epinephrine can be repeated every 3-5 min. Patient history, physical exam findings, and laboratory evaluation should be used to elicit correctable causes of arrest (such as the 6 Hs and 4 Ts) (see Table 62-5). CPR should be continued after epinephrine administration, to circulate the drug through the body. After 5 cycles of CPR, providers should reassess the child for the presence of a pulse or a change in the ECG rhythm that would necessitate a different response.

Figure 62-18 Pediatric advanced life support pulseless arrest algorithm.

For those children with pulseless VT or VF, emergency defibrillation is indicated (see Fig. 62-18). Providers should apply the pads to the child’s bare chest and back and follow the verbal instructions given by the AED. For younger children, a defibrillator (if available) set to the dose of 2 joules/kg should be used. Ideally, the AED used in a child ≤8 yr should be equipped with an attenuated adult dose or should be designed for children; if neither device is available, a standard adult AED should be used. CPR should be immediately restarted after defibrillation. Emergency dose epinephrine can also be administered with another 5 cycles of CPR to ensure its circulation throughout the child’s body. If the ECG rhythm continues to show VF or VT, defibrillation can be alternated with epinephrine. For refractory VF or VT, an IV antiarrhythmic, such as amiodarone or lidocaine, can be given (Tables 62-6 and 62-7).

Table 62-6 MEDICATIONS FOR PEDIATRIC RESUSCITATION AND ARRHYTHMIAS

MEDICATION	DOSE	REMARKS
Adenosine	0.1 mg/kg (maximum 6 mg)	Monitor ECG
Adenosine	Repeat: 0.2 mg/kg (maximum 12 mg)	Rapid IV/IO bolus
Amiodarone	5 mg/kg IV/IO; repeat up to 15 mg/kg	Monitor ECG and blood pressure
	Maximum: 300 mg	Adjust administration rate to urgency (give more slowly when perfusing rhythm is present)
	Maximum: 300 mg	Use caution when administering with other drugs that prolong QT interval (consider expert consultation)
Atropine	0.02 mg/kg IV/IO	Higher doses may be used with organophosphate poisoning
	0.03 mg/kg ET*
	Repeat once if needed
	Minimum dose: 0.1 mg
	Minimum single dose:
	Child, 0.5 mg
	Adolescent, 1 mg
Calcium chloride (10%)	20 mg/kg IV/IO (0.2 mL/kg)	Slowly
Calcium chloride (10%)	20 mg/kg IV/IO (0.2 mL/kg)	Adult dose: 5-10 mL
Epinephrine	0.01 mg/kg (0.1 mL/kg 1 : 10,000) IV/IO	May repeat q3-5 min
	0.1 mg/kg (0.1 mL/kg 1 : 1,000) ET*
	Maximum dose: 1 mg IV/IO; 10 mg ET
Glucose	0.5-1 g/kg IV/IO	D10W: 5-10 mL/kg
		D25W: 2-4 mL/kg
		D50W: 1-2 mL/kg
Lidocaine	Bolus: 1 mg/kg IV/IO
	Maximum dose: 100 mg
	Infusion: 20-50 µg/kg/min
	ET*: 2-3 mg
Magnesium sulfate	25-50 mg/kg IV/IO over 10-20 min; faster in Torsades de pointes
Magnesium sulfate	Maximum dose: 2g
Naloxone	<5 yr or ≤20 kg: 0.1 mg/kg IV/IO/ET*	Use lower doses to reverse respiratory depression associated with therapeutic opioid use (1-15 µg/kg)
Naloxone	≥5 yr or >20 kg: 2 mg IV/IO/ET*
Procainamide	15 mg/kg IV/IO over 30-60 min	Monitor EGG and blood pressure
Procainamide	Adult dose: 20 mg/min IV infusion up to total maximum dose of 17 mg/kg	Use caution when administering with other drugs that prolong QT interval (consider expert consultation)
Sodium bicarbonate	1 mEq/kg/dose IV/IO slowly	After adequate ventilation

ECG, electrocardiogram; ET, endotracheal tube; IO, intraosseous; IV, intravenous.

* Flush with 5 mL of normal saline and follow with 5 ventilations.

From ECC Committee, Subcommittees and Task Forces of the American Heart Association: 2005 American Heart Association guidelines for cardiopulmonary resuscitation and emergency cardiovascular care, Circulation 112:IV1–203, 2005.

Table 62-7 MEDICATIONS TO MAINTAIN CARDIAC OUTPUT AND FOR POST-RESUSCITATION STABILIZATION *

MEDICATION	DOSE RANGE	COMMENT
Inamrinone	0.75-1 mg/kg IV/IO over 5 min; may repeat 2×; then: 2-20 µg/kg/min	Inodilator
Dobutamine	2-20 µg/kg/min IV/IO	Inotrope; vasodilator
Dopamine	2-20 µg/kg/min IV/IO in low doses; pressor in higher doses	Inotrope; chronotrope; renal and splanchnic vasodilator
Epinephrine	0.1-1 µg/kg/min IV/IO	Inotrope; chronotrope; vasodilator in low doses; vasopressor in higher doses
Milrinone	50-75 µg/kg IV/IO over 10-60 min then 0.5-0.75 µg/kg/min	Inodilator
Norepinephrine	0.1-2 µg/kg/min	Inotrope; vasopressor
Sodium nitroprusside	1-8 µg/kg/min	Vasodilator; prepare only in D5W

IO, intraosseous; IV, intravenous.

* Alternative formula for calculating an infusion: Infusion rate (mL/hr) = [weight (kg) × dose (µg/kg/min) × 60 (min/hr)]/concentration µg/mL).

Vascular Access

Venous Access

Veins suitable for cannulation are numerous, but there is considerable anatomic variation from patient to patient. In the upper extremities, the median antecubital vein, located in the antecubital fossa, is often the largest and easiest to access (Fig. 62-19). Many veins on the dorsum of the hand are also suitable for cannulation because they are often large and easily located on the flat surface of the dorsum of the hand, and their cannulation is well tolerated. The cephalic vein is usually cannulated at the wrist, along the forearm, or at the elbow. The median vein of the forearm is also suitable because it lies along a flat surface of the forearm. In the lower extremity, the great saphenous vein, located just anterior to the medial malleolus, is accessible in most patients. The dorsum of the foot usually has a large vein in the midline, passing across the ankle joint, but catheters are difficult to maintain in this vein because dorsiflexion tends to dislodge them. A second large vein on the lateral side of the foot, running in the horizontal plane, usually 1-2 cm dorsal to the lower margin of the foot, is preferable (Fig. 62-20). The most notable scalp veins are the superficial temporal (just anterior to the ear) and posterior auricular (just behind the ear).

Figure 62-19 Veins of the upper extremity.

(From Roberts JR, Hedges JR, editors: Clinical procedures in emergency medicine, ed 4, Philadelphia, 2004, Saunders.)

Figure 62-20 Veins of the lower extremity.

(From Roberts JR, Hedges JR, editors: Clinical procedures in emergency medicine, ed 4, Philadelphia, 2004, Saunders.)

Deeper and larger central veins can provide more reliable, larger-bore access for medications, nutritive solutions, and blood sampling than peripheral venous lines. They may be reached by percutaneous cannulation or surgical exposure. In infants and young children, the femoral vein is often the easiest to access and cannulate, but the internal jugular and subclavian veins may also be used (Figs. 62-21 and 62-22). Because of its proximity to the median nerve, the brachial vein is not often recommended for cannulation.

Figure 62-21 Femoral vein approach. Remember the mnemonic NAVEL for nerve, artery, vein, empty space, and lymphatics.

(From Putigna F, Solenberger R: Central venous access [website]. http://emedicine.medscape.com/article/940865-overview. Accessed February 7, 2011.)

Figure 62-22 Internal and external jugular veins. EJ, external jugular vein; FV, facial vein; IJ, internal jugular vein; RMV, retromandibular vein; ST, superior thyroid vein. The 2 heads of the sternocleidomastoideus are indicated by the lines.

(From Mathers LW, Smith DW, Frankel L: Anatomic considerations in placement of central venous catheters, Clin Anat 5:89, 1992. Reprinted by permission of Wiley-Liss.)

Intraosseous Access

Intraosseous (IO) needles are special rigid, large-bore needles that resemble those used for bone marrow aspiration. IO cannulation is recommended for patients for whom IV access proves difficult or unattainable, even in older children. If venous access is not available within 1 min in a child with cardiopulmonary arrest, an IO needle should be placed in the anterior tibia (with care taken to avoid traversing the epiphyseal plate). The needle should penetrate the anterior layer of compact bone, and its tip advanced into the spongy interior of the bone (Fig. 62-23). Any and all medications, blood products, and fluids may be administered through this route, including those involved in emergency resuscitations.

Figure 62-23 Intraosseous cannulation technique.

(From Zwass MS, Gregory GA: Pediatric and neonatal intensive care. In Miller RD, Eriksson LI, Fleisher LA, et al, editors: Miller’s anesthesia, ed 7, Philadelphia, 2009, Churchill Livingstone, Fig 84-1.)

Arterial Access

Arterial access is indicated when care providers need frequent blood sampling, particularly to assess adequacy of oxygenation, ventilation, or acid-base balance, and/or continuous blood pressure monitoring. The radial artery, the most commonly cannulated artery, lies on the lateral side of the anterior wrist, just medial to the styloid process of the radius (Fig. 62-24). The ulnar artery, just lateral to the tendon of the flexor carpi ulnaris, is used less often because of its proximity to the ulnar nerve. Useful sites in the lower extremity, particularly in neonates and infants, are the dorsalis pedis artery, on the dorsum of the foot between the tendons of the tibialis anterior and the extensor hallucis longus, and the posterior tibial artery, posterior to the medial malleolus. Arterial catheters require special care for insertion and subsequent management because the blood flow to tissue can be compromised and considerable hemorrhage can occur if an arterial catheter is dislodged.