Bag-mask ventilation can be as effective as, and possibly safer than, endotracheal intubation for short periods of time in an out-of-hospital setting. If skilled personnel and proper equipment are available, pediatric patients requiring resuscitation should be endotracheally intubated. Before intubation, the patient should be ventilated with 100% oxygen using a bag and mask. Cricoid pressure should be used to minimize inflation of the stomach. Many conscious patients may benefit from the use of induction medications (sedatives, analgesics, and paralytics) to assist intubation, but caution is necessary to prevent further cardiovascular compromise from vasodilating effects of many sedatives. The correct size of the tube may be estimated according to the size of the child’s mid-fifth phalanx or the following formula: 4 + (patient age in years/4).
When the endotracheal tube is in place, the adequacy of ventilation and the position of the tube must be assessed. Use of both clinical assessment and confirmatory devices is recommended. Clinical assessment may include looking for adequate chest wall movement and auscultation of the chest to detect bilateral and symmetric breath sounds. Confirmatory devices such as end-tidal carbon dioxide (CO2) monitoring devices are useful for validation of endotracheal placement, but low levels of detected CO2 may be seen secondary to lack of pulmonary circulation. If the patient’s condition fails to improve or deteriorates, consider the possibilities of tube Displacement or Obstruction, Pneumothorax, or Equipment failure (mnemonic DOPE).
The major role of endotracheal intubation is to protect or maintain the airway and ensure the delivery of adequate oxygen to the patient. Because hypoxemia is the final common pathway in pediatric cardiopulmonary arrests, providing oxygen is more important than correcting the respiratory acidosis. The clinician should deliver 100% oxygen at a rate of 8 to 10 breaths/min during CPR, or 12 to 20 breaths/min for a patient who has a perfusing rhythm. Use only the tidal volume necessary to produce visible chest rise. Care should be taken not to hyperventilate the patient.
When mechanical means fail to re-establish adequate circulation, pharmacologic intervention is essential (Table 38-4).If intravascular access is not present or rapidly established, administration through an intraosseous route is recommended. Some drugs can also be administered effectively through the endotracheal tube.
Epinephrine, a catecholamine with mixed α-agonist and β-agonist properties, constitutes the mainstay of drug therapy for CPR. The α-adrenergic effects are most important during acute phases of resuscitation, causing an increase in systemic vascular resistance that improves coronary blood flow. Standard dose therapy is recommended for the first and subsequent boluses. There is no benefit offered by high-dose epinephrine. Vasopressin, an endogenous hormone, causes constriction of capillaries and small arterioles and may be useful. Insufficient data support its routine use, but vasopressin may be considered in children failing standard medication administration.
The routine use of sodium bicarbonate is currently not recommended. Sodium bicarbonate may be judiciously used to treat toxidromes or hyperkalemic arrest; however, oxygen delivery and elimination of CO2 must be established first. Side effects include hypernatremia, hyperosmolality, hypokalemia, metabolic alkalosis (shifting the oxyhemoglobin curve to the left and impairing tissue oxygen delivery), reduced ionized calcium level, and impaired cardiac function.
Routine administration of calcium is not recommended. It may be useful in cases of documented hypocalcemia, calcium channel blocker overdose, hypermagnesemia, or hypokalemia, but is otherwise not beneficial and potentially harmful.
Hypoglycemia is not uncommon in infants and children who sustain cardiac arrest. Blood glucose should be checked and hypoglycemia should be promptly treated with glucose.