Recognition of the critically ill child

RECOGNITION OF THE CRITICALLY ILL CHILD

I.     INTRODUCTION

Children are often unable, or unwilling to verbalize complaints. In addition, symptoms and signs of sepsis or cardio-respiratory compromise are often vague and subtle in children.

The ability to assess and recognize an ill child early allows for simple interventions and therapy such as ventilatory support, fluid resuscitation or early antibiotics to reverse potentially life- threatening cardiopulmonary instability.

II.   ANATOMIC AND PHYSIOLOGICAL CONSIDERATIONS

The paediatric respiratory system is ill-designed to cope with an increased work of breathing. The reasons are multi-factorial and include a relatively large tongue and floppy epiglottis, small airways with increased airway resistance, and increased chest wall compliance due to a cartilaginous chest wall.

Cardiac output is a function of stroke volume and heart rate. An infant has a limited ability to increase stroke volume in response to shock, and therefore mounts a tachycardia response to compensate for a drop in cardiac output. In addition, children have a higher oxygen consumption per kilogramme body weight than adults. As a result, they tolerate hypoxia poorly, and may manifest with tachycardia as a first sign of compensated shock.

III.  HISTORY

Functionality of the child is a simple but effective measure of how ill the child is. Questions to ask include:

•      Level of activity/play

•      Conscious level/irritability

•      Feeding/fluid intake

•      Urine output

Danger signs in the history include:

•      High-pitched cry/inconsolable crying

•      Grunting

•      Cyanosis

•      Apnoeic episodes

•      Pallor, cool and clammy peripheries

•      Shortness of breath or dyspnoea

•      Acute change in mentation

•      Focal seizures

•      Bloody stool in a neonate

Is there a significant medical history such as:

•      Maternal history of GBS or other neonatal infection risk factor (in a neonate)

•      Congenital cardiac defects

•      Primary immunodeficiency syndromes

•      Chronic steroid usage

•      Haem-oncological disorders on active chemotherapy

•      History of adreno-cortical deficiency e.g. hypopituitarism, congenital adrenal hyperplasia, hypothalamic or pituitary lesions

IV.  VITAL PARAMETERS

Hypotension is defined as systolic BP:

< 60mmHg in a neonate

< 70mmHg in infants (one to12 months)

< 70mmHg + [2 x (Age in Years)] in children one to ten years

< 90mmHg in children > ten years age

Mean arterial pressure can be calculated as {50 + [2 x (Age in Years)}mmHg.

Pulse pressure (systolic minus diastolic BP) is usually greater than 20mmHg. A widened pulse pressure is present in distributive shock, a narrow pulse pressure may suggest hypovolemic or cardiogenic shock. Unexplained tachycardia may be one of the first signs of compensated shock.

V.   PHYSICAL EXAMINATION

Clinical states which can rapidly progress and are life-threatening include:

•      Impending respiratory arrest

•      Cardiovascular instability/cardiogenic shock

•      Sepsis/septic shock

•      Severe dehydration

•      Seizures/altered mental state

•      Trauma

Danger signs in the physical examination which may indicate an unwell child include:

•      General appearance:

- Mottling of the skin

- Pallor

- Cool peripheries

- Lethargy/irritability

- Bulging tense fontanelles

- Purpuric rash

- Bruising/petechial rash

- Hyper-pyrexia (> 40°C)

•      Respiratory system:

- Cyanosis

- Tachypnoea/bradypnoea by age

- Kussmaul’s respirations

- Grunting

- Nasal flaring

- Retractions

- Audible stridor with drooling

•      Cardiovascular:

- Delayed capillary refill time (> two seconds)

- Weak/thready pulses

- Tachycardia/bradycardia by age

- Cardiac arrhythmias

- New onset murmur

- Gallop rhythm

- Absent femoral pulses (neonate)

•      Neurological:

- Focal neurological signs

- Rapidly decreasing conscious level or Glasgow Coma Score (GCS) < 13

- Change in mentation

- Asymmetrical pupillary reflex

•      Trauma:

- Penetrating injury of chest or abdomen

- Suspected spinal cord injury

- Flail chest

- Skull fracture

- Facial burns or burns involving > 10% Body Surface Area (BSA)

If a danger sign is present in the history and/or physical examination, consider the following:

•      Admit for observation

•      Call for senior help if there is evidence of severe respiratory distress, poor perfusion and/or hypotension, obtundation/change in mentation, prolonged seizure or cardiac arrhythmias

VI.  INVESTIGATIONS

•      Blood sugar: Exclude hypoglycaemia or DKA as a cause for obtundation

•      Blood gas analysis with electrolytes: Evaluate for severe acidosis, sodium/potassium/calcium derangements

•      Full Blood Count, U/E/Cr and group and match

•      Imaging: CXR to exclude pulmonary pathology, cardiomegaly. CT head if there are concerns regarding intracranial pathology

•      Septic screen including blood and urine cultures if sepsis is suspected. Consider CSF

cultures if an intra-cranial infection is suspected

•      LFT/coagulation profile if suspected liver dysfunction/bleeding diathesis

•      Serum lactate if available. This reflects tissue hypoperfusion and can be used as a marker of response to therapy

•      Metabolic screen if there is unexplained severe metabolic acidosis/ hypoglycaemia

•      Drug toxicology screen if suspected

VII. ACUTE TREATMENT

•      Ensure adequate oxygenation: Administer 100% oxygen nonrebreather facemask if hypoxia is present

•      Assess and maintain a patent airway: Consider intubation and assisted ventilation if there are concerns about hypoventilation or inability to maintain airway reflexes

•      Evaluate for haemodynamic compromise: Secure IV access early, consider intra-osseous access if venous access is difficult. Administer fluid resuscitation if there are signs of shock e.g. tachycardia, prolonged capillary refill time, cool peripheries. Give IV crystalloids in aliquots of 20ml/kg boluses and watch for response. If there is suspicion of cardiogenic shock, give fluids cautiously and consider early inotropic support (see management of shock).

•      Correct rapidly reversible, potentially life-threatening derangements. This includes:

- Hypoglycaemia: IV dextrose 10% 4–5ml/kg or dextrose 25% 1–2ml/kg

- Hyponatraemia: IV 3% NaCl 2ml/kg over 30 minutes

- Hyperkalaemia: IV insulin 0.1units/kg + IV dextrose 50% 2ml/kg and/or  sodium

polystyrene sulphonate (kayexalate) PR/oral 0.5–1g/kg

- Hypocalcaemia: IV 10% Calcium chloride 0.2ml/kg over ten minutes)

•      Early antibiotic therapy if sepsis is suspected

•      Transfer patient to an appropriate care facility after initial stabilisation

VIII. MONITORING

•      Continuous pulse oximetry, heart rate and respiratory rate monitoring

•      Close BP monitoring: Consider invasive BP monitoring if there are concerns about haemodynamic instability

•      Conscious level monitoring

•      Urine output as a marker of perfusion and end-organ function

REFERENCES (BIBLIOGRAPHY)

1-  2005 American Heart Association (AHA) Guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiovascular care (ECC) of pediatric and neonatal patients: Pediatric advanced life support. Pediatrics. 2006;117(5):1005–1028.

2-  Advanced Life Support Group. Advanced paediatric life support: The practical approach. 4th ed. London: Blackwell Publishing; 2005.

3-  Mejia R, Serrao K. Assessment of critically ill children. In: Mejia R, editor. Pediatric fundamental critical care support. Mount Prospect, Ilinois: Society of Critical Care Medicine;

2008. p. 1.1–121.

4-  Shann F. Drug Doses. 13th ed. Melbourne: Collective Pty Ltd; 2005.