Introduction
Cardiopulmonary arrest in pediatrics is a rare phenomenon. A sudden cardiac arrest is uncommon in children. In children, cardiac arrest occurs as a secondary event precipitated by a different set of causes. It occurs after a deterioration of the circulatory or respiratory function leading to respiratory failure with hypoxia (absence of oxygen in the tissues), acidosis, and decreased blood flow to the tissues or hemodynamic collapse. Respiratory failure resulting in lower than normal oxygen levels in the blood, increased carbon dioxide concentration in the blood, and an exceedingly acidic environment is the most common pathway for cardiac arrest in young children.
When Is Pediatric Resuscitation Indicated?
Pediatric resuscitation is indicated in the following cases:
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If the child becomes cyanotic or bluish discoloration of the skin due to reduced oxygen supply.
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If the child is asystolic (heart failure).
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Heart rate is less than 60 beats per minute.
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Shock.
How Is Pediatric Resuscitation Carried Out?
Pre-cardiac Arrest
Slow heart rate in a child is a sign of cardiac arrest, and infants, neonates, and young kids are more likely to develop bradycardia or slow heart rate due to lower than normal oxygen levels in the body (hypoxemia), whereas older children have a tendency towards increased heart rate (tachycardia). An infant or young child with a heart rate of less than 60 per minute and signs of poor perfusion, which does not rise with ventilatory support, should undergo cardiac compressions.
Chest Compression
During chest compressions in infants and children weighing less than 55 kg, the chest should be compressed one-third of the anteroposterior diameter, which is around four to five cm. In adolescents or children weighing more than 55 kg, the compression should be around five to six cm. The compression rate in infants and children is 100 to 120 compressions per minute.
Medications
Epinephrine is the drug of choice after proper ventilation and oxygenation and should be immediately administered after the establishment of intravenous (IV) or intraosseous (IO) access. 0.01 mg/kg of Epinephrine should be administered intravenously (IV), which can be repeated every three to five minutes. According to the present guidelines, immediate intraosseous access and Epinephrine administration for non-shockable rhythms should be given as the restoration of spontaneous circulation (ROSC), and the survival rate in children is related to the speed at which the first dose of Epinephrine is received.
If defibrillation or the use of electrical current for establishing the normal heart rhythm is unsuccessful after the administration of Epinephrine, then Amiodarone 5 mg/kg can be administered intravenously. It can be repeated up to two times for refractory ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT). Lidocaine can be given at a dose of 1 mg/kg intravenously, followed by a maintenance infusion of 20 to 50 mcg/kg/minute in case of unavailability of Amiodarone.
Blood Pressure
Blood pressure in children should be measured with an appropriate-sized cuff. Direct invasive arterial blood pressure should be monitored in severely compromised children. Children maintain their blood pressure longer because of stronger compensatory mechanisms such as increased systemic vascular resistance and increased heart rate. Once low blood pressure occurs, cardiorespiratory arrest follows rapidly. Treatment should be started when compensatory signs of shock such as cool extremities, increased heart rate, capillary refill of more than two seconds, and poor peripheral pulses are present but before low blood pressure develops.
Equipment
The size of the equipment, drug dosage, and cardiopulmonary resuscitation parameters all change with the age and weight of the children. Size-variable equipment includes ventilation bags, defibrillator paddles or electrode pads, masks, airways, endotracheal tubes, laryngoscope blades, and suction catheters. Weight should be correctly measured, or the commercially available measuring tapes calibrated to read the weight based on body length can be used. Some tapes come with the recommended drug dosage and equipment size for each weight.
Management of Temperature
Infants and kids are susceptible to loss of heat because of a larger surface area relative to body mass and less subcutaneous tissue. A neutral temperature is important during cardiopulmonary resuscitation and post-resuscitation. Hypothermia with a temperature lesser than 35 degrees Celsius makes resuscitation difficult. For children in a coma, the American Heart Association and American Association of Pediatrics guidelines advise therapeutic hypothermia of 32 to 36 degrees Celsius or normothermia of 36 to 37.5 degrees Celsius. Fever should be treated promptly.
Airway and Ventilation
The anatomy of the upper airway is different in children. The head is large with a small face, lower jaw, and nose, and the neck is relatively short. The tongue is large as compared to the mouth, and the larynx or sound box lies higher in the neck and is placed more anteriorly. The epiglottis is long, and some part of the wind pipe or trachea is inferior to the vocal cords, thus allowing the use of uncuffed endotracheal tubes. In infants and young kids, a straight laryngoscope blade gives a better picture of the vocal cords than a curved blade because the larynx is placed anterior, and the epiglottis is more floppy. In case of the absence of an advanced airway in infants and children undergoing resuscitation, the compression: ventilation ratio is 30:2. This is in contrast to adults where the compression: ventilation ratio is 30:2. With an advanced airway, usually one breath is given every six seconds (ten breaths per minutes) for infants, children, and adults.
Defibrillation
About 15 to 20 percent of pediatric cardiac arrests have ventricular defibrillation (VF) and pulseless ventricular tachycardia (VT). The medication Vasopressin is not indicated. During defibrillation, the energy dose is less than what is used in adults. Automated external defibrillators (AEDs) with adult cables may be used for children as young as one year old, but an automated external defibrillator with pediatric cables is preferred for children between the age group of one to eight years.
What Are the Complications of Pediatric Resuscitation?
The long-term treatment is restricted to child-specific centers. ECMO (extracorporeal membrane oxygenation) or ECPR (extracorporeal cardiopulmonary resuscitation) should be considered early for in-hospital cardiac arrests.
Age is usually correlated with improved post-resuscitation outcomes, and post-arrest brain injury remains a cause of mortality and morbidity in young children. Therefore, electroencephalograms and seizure prophylaxis are recommended for such patients after the return of spontaneous circulation.
Conclusion
Pediatric and neonatal resuscitation involves approaches to achieve the return of spontaneous circulation (ROSC), which is the same as adult cardiorespiratory resuscitation but requires special considerations with regard to medication, procedures, and aftercare. Cardiac arrest in children is rarely abrupt and is the end result of deterioration in respiratory function. The survival rate in pediatric patients with cardiac arrests has increased from 9 to 41 percent. These improvements are caused due to earlier detection and management of critical conditions such as cardiopulmonary resuscitation and medical emergency teams trained in acute resuscitation of pediatric patients.
