Foreign body removal maneuvers consist of a sequence of five back blows and five chest thrusts for infants and the Heimlich maneuver for children (Fig. 13.1). Blind finger sweeps should not be performed in children because a partial obstruction can be turned into a full obstruction if the foreign body is pushed further into the airway. Because of the pliability of the esophageal wall, foreign bodies in the esophagus can impinge on the trachea and result in airway obstruction. If the foreign body cannot be removed with basic life support maneuvers and the patient decompensates, the clinician can attempt to remove any visible foreign body with Magill forceps. Intubation may be required, and it may be possible to push the foreign body into a mainstem bronchus, most commonly on the right side. If this maneuver fails and the patient cannot be intubated, the last resort is either needle cricothyrotomy or a surgical airway. In a stable patient, bronchoscopy with maintenance of the patient’s position of comfort is the treatment of choice.

Fig. 13.1 Foreign body removal techniques in infants and children.

Airway Management

Airway management in children can be anxiety provoking; the same preparation guidelines outlined in Chapter 1 should be followed. Signs of respiratory failure include an increased or decreased respiratory rate, nasal flaring, grunting, retractions, cyanosis, apnea, or altered mental status. Hypoxia, compromised airway protection, altered mental status, and impending respiratory failure are common indications for pediatric airway intervention. Because most pediatric cardiac arrests are secondary to respiratory failure, early airway intervention is crucial.

Anatomy

The pediatric airway differs significantly from the adult airway (Box 13.1), and some special techniques are helpful when intubating a child. An oral or nasal airway can assist in maintaining airway patency. Because of the large occiput in a young child, typically those younger than 1 year, a towel roll placed beneath the patient’s shoulders often improves airway alignment. To visualize the very anterior pediatric airway, the operator must look up during intubation and may need to squat or raise the bed for adequate viewing. To see the glottic opening, a straight blade is recommended to lift up an infant’s floppy omega-shaped epiglottis. Because of infants’ small mouths, an assistant may need to pull the baby’s cheek to the side to allow passage of the laryngoscope and endotracheal tube.^1,²

Box 13.1 Ways in Which a Child’s Airway Differs Anatomically from an Adult’s Airway

The prominent occiput can cause airway obstruction and impede glottic visualization during intubation; a 1-inch towel roll should be placed below the shoulders

Dependence on nasopharynx patency; nasal airways should be avoided in children younger than 1 year because their larger adenoidal tissue can bleed

Copious secretions

Loose primary teeth

The relatively larger tongues can obstruct the airway and often necessitate an oral or nasal airway

The epiglottis is omega (Ω) shaped and floppy; a straight laryngoscope blade is used to lift the epiglottis out of view

The larynx is more anterior and cephalad

The cricoid is the narrowest portion of the airway

Small tracheal diameter and distance between rings, which makes tracheostomy or cricothyrotomy more difficult; the American Heart Association recommends needle cricothyrotomy for difficult airways (see text discussion of this modality)

Much shorter tracheal length (newborn, 4 to 5 cm; 18-month-old child, 7 to 8 cm)

The endotracheal tube may easily be dislodged; frequently reassess position of the tube

Greater airway resistance

Increased risk for aspiration and diaphragmatic dependence *

^* Decompress the stomach to facilitate ventilation; a rough guide to nasogastric tube size is twice the endotracheal tube size.

Rapid-Sequence Intubation in Children

The intubating time line and drugs of choice are listed in Tables 13.1 and 13.2. Postintubation assessment includes confirmation that the endotracheal tube is in correct position. First listen over the stomach and then over the axillae for breath sounds. A confirmatory device such as an end-tidal carbon dioxide monitor, a carbon dioxide chart (e.g., Pedi-Cap, which should change from purple to yellow with proper tube placement), or an esophageal detector should be used.^3,⁴ A nasogastric or orogastric tube should also be placed as soon as possible because any amount of gastric distention can make ventilation and oxygenation of a child difficult. A rough rule of thumb for nasogastric and orogastric tube size is two times the endotracheal tube size.

Table 13.1 Paralytic Agents Commonly Used for Intubation in Children*

Table 13.2 Induction Agents for Intubation in Children

Pharmacologic Agents for Rapid-Sequence Intubation in Children

Potential combinations of agents for rapid-sequence intubation are listed in Table 13.3. Pretreatment with multiple agents is not recommended because placement of an advanced airway may be delayed. Atropine has recently been called into question for routine use in pediatric intubation, but it is recommended in infants younger than 1 year to avoid the bradycardia associated with airway manipulation in this population. The dose of atropine ranges from 0.01 to 0.02 mg/kg (minimum dose, 0.1 mg).

Table 13.3 Clinical Scenarios for Intubation and Recommended Induction Agents

CLINICAL SCENARIO	INDUCTION AGENTS
Isolated head injury	Propofol Thiopental Etomidate ? Do not use ketamine *
Status epilepticus	Thiopental Propofol Etomidate Midazolam

Asthma

Ketamine

Etomidate

DO NOT USE thiopental

Respiratory failure

Ketamine

Etomidate

Propofol

^* Several intensive care unit studies have shown that in intubated patients, ketamine does not increase intracranial pressure and may help maintain cerebral perfusion pressure. However, no emergency department studies have been performed to date.

Adapted from a presentation by Sacchetti A. Boston: American College of Emergency Physicians Scientific Assembly; 2003.

Principles of Endotracheal Intubation

Recommended endotracheal tube sizes are listed in Box 13.2. With the advent of high-volume, low-pressure cuffed endotracheal tubes, the dictum of using only uncuffed endotracheal tubes in children younger than 8 years has changed. It is not only acceptable but at times preferable (high peak pressure) to use a cuffed endotracheal tube in children. For an approximate guide to tube size, use 4 + (age ÷ 4) for uncuffed tubes and 3.5 + (age ÷ 4) for cuffed tubes. Cuff inflation pressure should be kept less than 20 to 25 cm H₂O. Cuffed endotracheal tubes are not recommended for use in neonates.^5,⁶

Table 13.4 summarizes the procedure for rapid-sequence intubation in children.

Table 13.4 Procedure for Rapid-Sequence Intubation in Children

Time to intubation 5 min	Start preoxygenation
Time to intubation 3 min	Give any premedication (atropine, lidocaine)
Intubation time	Push induction and paralytic agents
After the patient is relaxed	Intubate:
	Apply cricoid pressure
	Use the BURP (backward, upward, and rightward pressure) technique*
Immediately after intubation	Release cricoid pressure
	Secure the endotracheal tube
	Place a nasogastric tube

^* Too much pressure can occlude the airway.

An incorrect endotracheal tube size can lead to an inability to ventilate if the tube is too small or result in airway trauma (e.g., subglottic edema) if the tube is too large. Easy formulas for estimating the depth of endotracheal tube placement are as follows:

3 × endotracheal tube size; for example, a 4.0-mm tube placed with the 12-cm mark at the gum line

10 + age in years = number of centimeters of the tube to the lips

For premature infants, the following estimations of tube depth based on body weight are helpful:

Approximate laryngoscope sizes are listed in Table 13.5. The Broselow-Luten resuscitation tape can also be used to select the weight-based appropriate size. It is important to remember that the actual blade size needed is determined by the individual patient’s weight, body habitus, and anatomic variability. Preparation is essential; having laryngoscope blades available that are one size smaller and one size larger than anticipated prevents costly delays.

Table 13.5 Choosing Laryngoscope Size and Type for a Child

AGE OR WEIGHT	LARYNGOSCOPE SIZE	LARYNGOSCOPE TYPE
2.5 kg	0	Straight
0-3 mo	1.0	Straight
3 mo-3 yr	1.5-2.0 or 1.5	Straight or curved
3 mo-3 yr	1.5-2.0 or 1.5	Wisconsin
3-12 yr	2.0-4.0	Straight or curved

Once endotracheal tube placement is confirmed, the tube must be secured. The endotracheal tube can be dislodged very easily, particularly in young infants with small tracheal widths. A cervical collar, even in the nontrauma setting, can minimize tube motion and dislodgement.

Breathing

Bag-Valve-Mask Ventilation

Self-inflating, hand-squeezed resuscitators are commonly used in children because of the elasticity of the self-inflating bag, which allows independent refilling. Many of these bags have a pressure-limited pop-off valve, typically set at 30 to 35 cm H₂O to prevent barotrauma. Sometimes higher pressure is required, depending on the child’s pathophysiology. Correct mask sizing is vital for proper bag-valve-mask ventilation. The mask should fit snugly from the bridge of the nose to the cleft of the chin. A mask that is too large can place pressure on the eyes and cause vagal bradycardia. A mask that is too small will not allow adequate oxygenation and ventilation. The mask should be held with a “CE” grip—the holder’s thumb and index finger grip the mask and the third, fourth, and fifth fingers are placed on the angle of jaw. It is important to avoid pushing on the soft tissue below the mandible, which can cause airway obstruction.

The rate of bagged breaths per minute is best controlled by having the operator say “squeeze-release-release” as the patient is being ventilated. This practice helps decrease the rapid rate of ventilation and resultant adverse effects of overinflation. Patients in full arrest with an advanced airway in place should not receive more than 8 to 10 breaths/min via either a bag-valve-mask ventilator or an endotracheal tube. Complications of bag-valve-mask ventilation include gastric distention, pneumothorax, vomiting, aspiration, and hypoxia.

Appropriate bag size can be chosen as follows:

• For an infant or child up to 5 years of age: 450-mL bag

• For an older child: 750-mL or adult bag

To prevent confusion in resuscitation situations, neonatal 250-mL bags, which are inadequate for any child older than a newborn, should be well labeled and stocked in a separate area with other newborn resuscitation equipment.

Initial Ventilator Settings

Initial ventilator settings are typically chosen through assessment of the height and weight of the patient and the underlying cause of the respiratory distress.

For children weighing less than 10 kg, a pressure-limited system should be used. The infant should be given sufficient oxygen to relieve cyanosis and maintain normal oxygen saturation (92% to 96%) or normal PO₂ (60 to 90 mm Hg). The following are recommended initial ventilator settings:

Rate: 20 to 60 breaths/min (goal PaCO₂, 35 to 45 mm Hg)

Fraction of inspired oxygen (FIO₂): 100% (wean slowly based on pulse oximetry)

Positive end-expiratory pressure (PEEP): 3 to 5 cm H₂O

Peak inspiratory pressure: 15 to 35 cm H₂O (or sufficient to produce discernible chest wall movement)

Inspiratory time–to–expiratory time (I/E) ratio: 1 : 2 (inspiratory time of 0.4 to 0.7 second)

For children weighing more than 10 kg, a volume-limited system should be used. The following are recommended initial ventilator settings:

Volume: 10 to 15 mL/kg (if plateau pressure is greater than 35 mm H₂O and for asthmatics, decrease to 6 to 8 mL/kg)

Rate: an for infant, 20 to 30 breaths/min; for a child, 15 to 20 breaths/min

FIO₂: 100% (wean slowly based on pulse oximetry)

PEEP: 3 to 5 cm H₂O

I/E ratio: 1 : 2

The Difficult Pediatric Airway

Failed Intubation

In the event that endotracheal intubation is unsuccessful, several options are available for airway rescue. The laryngeal mask airway (LMA) has the advantages of easy placement without the need for laryngoscopy and little cardiac effect during the insertion process. Disadvantages include the lack of airway protection from vomiting or aspiration of gastric contents, the requirement that the patient be unconscious or sedated for placement, and the fact that an LMA is not a definitive airway. Furthermore, in children less than 30 kg, higher ventilatory pressure may be required because the LMA can fold the epiglottis over and cause partial upper airway obstruction.

Approximate LMA sizes are listed in Table 13.6.

Table 13.6 Recommended Laryngeal Mask Airway Sizes

PATIENT AGE AND WEIGHT	SIZE
Neonates to 5 kg	1
Infants/children
5-10 kg
10-20 kg	2
20-30 kg
30-50 kg	3
Adults
50-70 kg	4
70-100 kg	5
>100 kg	6

Complications of LMA placement are partial upper airway obstruction, coughing or bronchospasm, aspiration or regurgitation, airway trauma, lingual nerve palsy, vocal cord paralysis, hypoglossal nerve paralysis, hoarseness, stridor, and pharyngeal or mouth ulcers.

Needle Cricothyrotomy (Jet Ventilation)

Needle cricothyrotomy should be used when endotracheal intubation is not successful. It is most often indicated in children younger than 10 to 12 years, in whom a surgical airway is technically difficult to perform. This chapter describes various oxygen setups that can be used in any emergency department to ventilate by needle cricothyrotomy without a jet ventilator attachment. The procedure for placing the needle is quite simple:

1. Identify the cricothyroid membrane; prepare with povidone-iodine solution if possible.

2. Use a 12- to 14-gauge angiocatheter attached to a syringe to puncture the cricothyroid membrane.

3. Direct the catheter at a 45-degree angle caudally (toward the patient’s feet). Placement of normal saline in the syringe helps demonstrate when air is aspirated.

4. Remove the needle from the angiocatheter.

With these methods the child can be oxygenated, but ventilation (CO₂ exhalation) is limited.

Methods of Ventilation

Once the angiocatheter is placed, one of the following methods may be chosen for ventilation:

• Attach the following items to the angiocatheter: a 3-mL syringe barrel, a 7.0 French (F) endotracheal tube adapter, and a bag-valve-mask ventilator. Turn the wall oxygen (O₂) up to 15 L and attempt to administer ventilation with the bag through the angiocatheter.

• Attach a 3.0 F endotracheal tube adapter directly to the angiocatheter and then a bag-valve-mask ventilator; turn the wall O₂ up to 15 L and attempt to administer ventilation with the bag and through the angiocatheter.

• Attach one prong of a nasal cannula to the angiocatheter and use the other prong for oxygen flow (1 second on for inspiration, 4 seconds off for expiration).

• Use an Enk Oxygen Flow Modulator Kit (Cook Medical).

• The QuickTrach kit (Rusch, Inc.) can also be used for cricothyrotomy.

Circulation

Volume resuscitation starts with 20 mL/kg of normal saline or lactated Ringer solution. In newborns, 10 mL/kg is a good starting point. Boluses may be repeated. In cases of hemorrhagic shock, if blood pressure does not improve after two or three boluses, packed red blood cells should be given at a dose of 10 mL/kg. The PALS formula for a blood pressure goal in children notes that the 5th percentile is 70 + (2 × age in years). Because this is only the 5th percentile, the preferred formula is 90 + (2 × age in years). Normal systolic blood pressure for term neonates is 60 mm Hg.

Shock results from inadequate blood flow and delivery of oxygen to meet the metabolic needs of the body. In children, the most common type of shock is hypovolemic. Compensated shock is defined by the presence of tachycardia, cool extremities, prolonged capillary refill time, and weak peripheral pulses with normal systolic blood pressure. Decompensated shock occurs when hypotension, weak central pulses, and weak or absent peripheral pulses develop. Table 13.7 lists the most commonly used medications for maintaining cardiac output and for postresuscitation stabilization.

Table 13.7 Postresuscitation Medications

MEDICATION	DOSE RANGE
Inamrinone	0.75-1 mg/kg IV/IO over 5-min period; may repeat twice, then 5-10 mcg/kg/min
Dobutamine	2-20 mcg/kg/min IV/IO
Dopamine	2-20 mcg/kg/min IV/IO
Epinephrine	0.1-1 mcg/kg/min IV/IO
Milrinone	Loading dose: 50 mcg/kg IV/IO over 10- to 60-min period, then 0.25-0.75 mcg/kg/min
Norepinephrine	0.1-2 mcg/kg/min
Sodium nitroprusside	Initially, 0.5-1 mcg/kg/min; titrate to effect up to 8 mcg/kg/min