Cardiopulmonary arrest is simply defined as the cessation of spontaneous respiratory effort and circulation manifest as apnoea, absence of central pulses and lack of responsiveness. Overall fewer than 10% of children suffering cardiopulmonary arrest survive to hospital discharge. As cardiopulmonary arrest is rarely seen in children, paramedics, the public and Emergency Department staff should familiarize themselves with national guidelines and published protocols. This has been made increasingly possible with the local availability of life support courses, namely Advanced Pediatric Life Support (APLS) and Pediatric Advanced Life Support (PALS).
The International Liaison Committee on Resuscitation (ILCOR) established in 1992 aimed to scrutinise existing scientific evidence, compare national differences and hence formulate recommendations that could subsequently be incorporated into international guidelines and used by individual resuscitation councils worldwide. ILCOR has the task of highlighting potential areas for future research and development and encouraging collaboration between the national resuscitation councils.
Pathophysiology
In contrast to the adult, primary cardiac pathology is rarely responsible for cardiopulmonary arrest in a child. It is more often the end result of respiratory insufficiency or circulatory failure. A state of tissue hypoxia and acidosis rapidly develops if respiratory insufficiency is allowed to proceed unrecognized or untreated. Ischemia to the end organs, namely heart, brain and kidney, occurs and cardiopulmonary arrest is the end point of prolonged and severe myocardial damage. Circulatory failure secondary to fluid/blood loss or maldistribution of fluid within the circulatory compartment can also eventually lead to cardiac arrest, for example secondary to severe gastroenteritis, burns, overwhelming sepsis and traumatic hemorrhage. In children, a period of prolonged hypoxia occurs in the prearrest state unlike the sudden cardiac event experienced in adults. This accounts for the extremely poor neurological outcome in survivors.
Basic life support
The prehospital provision of basic life support is essential to maintain perfusion of the vital organs until the facilities for advanced life support become available. Hence it is vital that increased public awareness and further education, to increase the pool of basic life support providers in the community, is encouraged, and that advanced life support providers are proficient with basic life support techniques to enable its continuous provision during resuscitation. The exact techniques in children vary in accordance with the age of the child and currently three categories exist—infants (under 1 year), small children (1–8 years) and larger children (>8 years).
Assessment and treatment
The appropriate sequence of assessment and treatment is as follows:
- Airway
- Breathing
- Circulation
Progression from airway to breathing should occur only when the airway has been appropriately assessed and secured, and similarly for breathing to circulation. Any deterioration in the child’s condition should prompt a rapid reassessment of the airway and subsequently breathing and circulation.
Prior to assessment of the child, additional help should be summoned. It is paramount to take care when approaching the victim to prevent the rescuer from becoming a second victim. Only commence evaluation of airway, breathing and circulation after the victim has been freed from existing danger—the so-called SAFE approach (Figure 2.1).
An assessment of responsiveness can be achieved by asking the simple question, ‘Are you alright?’, and gently shaking the arm. If there is a suspected cervical spine injury, a clinician should place a hand on the child’s forehead to immobilize the head throughout resuscitation to prevent further damage. Children may respond either verbally signifying a patent airway or by opening the eyes.
Airway
In the unconscious child, the large tongue has a tendency to fall backwards and obstruct the pharynx. Blind sweeps are contraindicated in children as a partial obstruction can be converted into a complete obstruction. The tissues of the soft palate are very friable and their tendency to bleed can further obstruct the airway. Attempts to improve the obstructed airway can be performed by various airway opening manoeuvres, including head tilt and chin lift. The head should remain in the neutral position in the infant but in the ‘sniffing the morning air’ position in the child (Figure 2.2a, b). Employ the jaw thrust maneuver if spine trauma is suspected (Figure 2.2c). Only proceed to assessment of the breathing once the airway is patent.
Circulation
To test for adequate circulation, palpation of the brachial pulse in the antecubital fossa or the femoral pulse in the groin should be performed in infants, as the carotid pulse is difficult to locate in this age group. In children over a year of age the carotid can be palpated. The absence of a central pulse for 10 seconds or a pulse rate of less than 60 beats per minute in a poorly perfused child necessitates commencement of cardiac compressions. Ideally the child should be positioned on his or her back on top of a hard surface. Correct hand positioning for cardiac compressions varies according to the age of
the child in three age bands:
• infant (<1 year)
• younger child (1–8 years)
• older child (>8 years) (see Table 2.1)
Common to all three age groups is a rate of compression of 100 per minute, the depth of compression of one-third of the depth of the chest wall. The ratio is one breath to five cardiac compressions in infants and young children, and two breaths to 15 compressions in the older child, regardless of number of rescuers (Table 2.1). Following completion of a minute or 20 cycles of cardiopulmonary resuscitation (CPR), the rescuer must seek assistance and call the emergency services if they have not already arrived. This is essential as basic life support merely supports perfusion of the vital organs and survival is virtually impossible unless the provision of advanced life support is ensured.
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