Cardiac arrest in children occurs when the heart suddenly stops beating effectively, leading to a cessation of blood flow. This differs from a heart attack, a “plumbing problem” involving a blocked artery. Pediatric cardiac arrest is rare, affecting approximately 8.04 per 100,000 children per year outside of a hospital setting.
Causes of Pediatric Cardiac Arrest
Unlike adults, where primary cardiac events are common, cardiac arrest in children often results from issues outside the heart, frequently stemming from respiratory failure or different forms of shock. Inadequate oxygen delivery, such as from severe respiratory infections or airway obstructions, can lead to hypoxia, depressing heart function and causing cardiac arrest. Severe dehydration or acute blood loss can also cause hypovolemic shock, leading to circulatory collapse and cardiac arrest.
Underlying cardiac issues, while less frequent as a primary cause, can also precipitate cardiac arrest in children. Congenital heart defects (CHDs) can increase risk due to abnormal blood flow or pressure. Children with CHDs may experience myocardial dysfunction, arrhythmias, or imbalanced circulation, especially after surgical repairs. Arrhythmias (abnormal heart rhythms) can also be inherited electrical disorders like Long QT syndrome or Wolff-Parkinson-White syndrome, causing erratic heartbeats. These channelopathies disrupt the heart’s electrical signals, potentially causing sudden death.
Diseases of the heart muscle, known as cardiomyopathy, represent another cardiac cause. Dilated cardiomyopathy, where heart chambers enlarge and weaken, and hypertrophic cardiomyopathy, involving abnormal thickening of the heart muscle, can both lead to heart failure, arrhythmias, and sudden cardiac arrest in young individuals.
External events are significant contributors. Trauma, particularly to the head or chest, can lead to respiratory failure or direct heart injury. Drowning or suffocation results in severe oxygen deprivation, leading to cardiac arrest. Severe infections like sepsis can also cause shock and multiorgan failure, increasing the likelihood of cardiac arrest in children.
Recognizing Warning Signs
Recognizing the signs of cardiac arrest in a child is important for prompt intervention. A sudden collapse where the child becomes unresponsive to touch or sound is the most obvious indication. They may appear limp with abnormal skin color, such as pallor or cyanosis.
A child in cardiac arrest will also exhibit absent or abnormal breathing patterns. This can manifest as no breathing (apnea) or only gasping, irregular breaths, often described as agonal breathing. Agonal breaths, which can sound like gasps or gulps, are not effective breathing and indicate a severe lack of oxygen. If there is any uncertainty about whether breathing is normal, it should be assumed that it is not.
It is important to differentiate these signs from conditions like fainting or seizures. During fainting, a child regains consciousness quickly, and a pulse and normal breathing are still present. While seizures can cause unresponsiveness and abnormal movements, breathing and a pulse are maintained, unlike cardiac arrest where both are absent.
Immediate Emergency Response
Immediate action is necessary upon recognizing the signs of pediatric cardiac arrest. First, ensure the scene is safe before approaching the child. Once safety is confirmed, gently tap the child’s shoulder and shout to check for responsiveness; for an infant, flicking the bottom of their foot can elicit a response. If there is no response, the next step is to activate emergency medical services.
If you are not alone, immediately direct a bystander to call 911 and locate an Automated External Defibrillator (AED). If you are alone with the child, perform approximately two minutes of CPR before calling 911 yourself. Emergency dispatchers can provide CPR instructions over the phone, which increases bystander CPR rates and improves survival outcomes.
Following the call for help, begin high-quality cardiopulmonary resuscitation (CPR). For children, place the heel of one or two hands in the center of the chest, pushing down about two inches at a rate of 100 to 120 compressions per minute. For infants, use two fingers or the two-thumb encircling technique in the center of the chest, compressing about 1.5 inches deep. After every 30 compressions, deliver two rescue breaths, ensuring the chest visibly rises with each breath.
As soon as an AED becomes available, turn it on and follow its audio and visual prompts. Pediatric AED pads, which deliver an attenuated energy dose, should be used for children under eight years old or weighing less than 55 pounds. If pediatric pads are unavailable, adult pads can be used, ensuring they do not touch each other on the child’s chest, possibly by placing one on the front and one on the back. The AED will analyze the heart’s rhythm and advise if a shock is needed, then guide the user through delivery, followed by immediate resumption of CPR.
Hospital Treatment and Recovery Outlook
Once emergency medical services arrive, advanced medical care for pediatric cardiac arrest patients begins with advanced cardiac life support, often following Pediatric Advanced Life Support (PALS) protocols. This involves identifying and treating reversible causes of the arrest, managing the airway with advanced ventilation techniques, and administering medications to support heart function and blood pressure. Common medications include epinephrine, used to improve blood flow during resuscitation, and antiarrhythmic drugs like amiodarone or lidocaine for specific heart rhythms.
After the return of spontaneous circulation, post-cardiac arrest care focuses on protecting the brain and other organs from secondary injury. This involves targeted temperature management (TTM), which aims to control the child’s body temperature. TTM may involve maintaining continuous normothermia (body temperature between 36°C to 37.5°C) or initiating a period of therapeutic hypothermia (cooling to 32°C to 34°C) for 24 to 48 hours, followed by controlled rewarming. Fever prevention is a standard component of post-arrest care, as elevated body temperature can worsen neurological outcomes.
The recovery outlook for children after cardiac arrest varies widely and is influenced by several factors. How quickly CPR was initiated by bystanders, the underlying cause of the arrest, and the duration of the arrest all play a significant role. Children who experience out-of-hospital cardiac arrest have lower rates of favorable neurological outcomes compared to those who have an in-hospital event. While some children may achieve a full recovery, others may experience a spectrum of neurological outcomes due to hypoxic-ischemic brain injury, which is a major concern. Prognostication is complex, and neurological recovery can extend over several months, necessitating ongoing rehabilitation and support.