Definition: Critical illness or sickness in a child is a clinical state that may result in respiratory or cardiac arrest or severe neurological complication if not recognized and treated promptly.

Causes:Primary cardiovascular, respiratory, neurological, infectious or metabolic disorders.

Goal:Rapid cardiopulmonary assessment in 30 seconds and classification of degree of sickness to start early treatment.

Classification based on AABC (appearance, airway, breathing and circulation):

1. Stable: alert, active, positive eye contact, responsive to voice and pain, normal tone and posture, pink, Capillary refill time (CRT) < 2 seconds, normal respiratory rate (RR), heart rate (HR) & BP.
2. Respiratory distress: RR >60/m (newborn), >50/m (2mo-1 yr), >40/m (1-5 yrs), work of breathing: nasal flaring, chest retraction, grunting.
3. Respiratory failure: Tachypnea as above with deterioration of respiratory distress - cyanosis, altered sensorium, poor muscle tone and poor respiratory efforts.
4. Compensated shock: peripheral signs with Normal BP.
5. De-compensated shock: peripheral signs with hypotension.
6. Cardio respiratory failure: respiratory failure, bradycardia or cardiac arrest.

ASSESSMENT: AABC
APPEARANCE:Alertness, distractibility or consolable, eye contact, speech or cry, motor activity etc. - denote neurological status which is determined by supply of oxygen and blood to the brain (cardiopulmonary status) and structural integrity of the brain. Besides seizure, abnormal posturing, muscle tone and pupillary reaction are noted.

1. Alertness: Changes in level of consciousness can be rapidly determined by AVPU.
   1. Awake: aware of the surroundings and interested in surroundings - determine if confused, irritable, lethargic or totally unaware of environment.
   2. Responsive to voice
   3. Responsive to pain
   4. Unresponsive
2. Distractibility or consolable by parent:normal in infants and young children.
3. Eye contact with parents or physician: noted normally at 2 months of age - absence of eye contact is an early ominous sign of cortical hypoperfusion and brain dysfunction.
4. Speech or cry: Cry- whether normal, whimpering, moaning or high pitched.
5. Motor activity: Normal movements of limb, trunk and neck.
6. Other features like:
   • Seizures with altered sensorium, a critically ill state as it may lead onto cardiorespiratory compromise or neurological sequelae if not treated.
   • Posture: intermittent flexor (decorticate) or extensor (decerebrate) with prolonged cerebral hypoperfusion.
   • Muscle tone:Hypotonia / limping is a bad sign.
   • Pupil size: Small but reactive pupils in cerebral hypoperfusion. Unequal pupils - a medical emergency and may indicate raised Intracranial pressure (ICP).
   
   

AIRWAY: Open and clear or maintainable with adjuncts like positioning and airways suction or non- maintainable without intubation.

BREATHING: Check breathing for 10 seconds - chest rise, listen for breath sounds and feel for exhaled air:

• RR: >60/m always abnormal and a sign of respiratory distress. Quiet tachypnea i.e., RR without increased work of breathing is seen in shock, heart disease and acidosis. A slow or irregular respiratory rate in an acutely ill child is ominous.
• Increased work of breathing (IWB): nasal flaring, grunting and intercostals, subcostal and suprasternal retractions suggest respiratory distress or potential respiratory failure. Head bobbing and seesaw respirations (severe chest retraction with abdominal distention) suggest advanced respiratory distress and impending respiratory failure.
• Air entry: Effective tidal volume is assessed by chest expansion and auscultation of breath sounds.
  Stridor: Upper airway obstruction like tongue fallen back, laryngomalacia, vocal cord paralysis, hemangioma, tumor, cysts, infection, edema, or aspiration of a foreign body.
  Wheezing: Intrathoracic obstruction like bronchiolitis, asthma, pulmonary edema or intrathoracic foreign body.
• Color of skin and temperature denote respiratory and circulatory status.

CIRCULATION:Assessed by HR, pulse for 10 seconds, BP to find out if the cardiac output meets the tissue demand.
Shock:Inadequate delivery of oxygen and substrates to meet the metabolic demands of tissues due to circulatory dysfunction. HR changes alone may be too early a sign of derangement and are often too nonspecific.

• HR: HR; a common response to stress including shock which if present mandates further evaluation. Bradycardia in critically ill child is ominous.
  Normal heart rate: < 3 mo (140/m), 3 mo-2yrs (130/m), 2-10 yrs (80/m), > 10 yrs (75/m).
  Tachycardia: > 180/m (< 5 yrs), > 160/m (> 5 yrs).
  Bradycardia: < 80/m (< 5 yrs), < 60/m (> 5 yrs).
• Pulse: Central (femoral, carotid and brachial) and peripheral (radial, dorsalis pedis and posterior tibial). Presence or absence of pulse, pulse volume, pulse pressure (PP) (systolic BP - diastolic BP) are noted.
  PP narrows as cardiac output and the pulse becomes thready. When cardiac output increases such as in septic or anaphylactic shock, the PP widens and pulses are bounding. Wide PP does not mean that perfusion is adequate. Loss of central pulse is a pre morbid sign and is to be treated as cardiac arrest.
• Blood pressure:
  Lower limit (5th percentile) of blood pressure -
  New born: 60 mm Hg systolic
  Up to 1 year: 70 mm Hg systolic
  2-8 year: 70 + (2 x Age in yrs) mm Hg
  Shock can be with normal BP as in early compensated shock, increased BP or decreased BP as in late or de-compensated shock when progression to irreversible shock or multiple organ failure or death rapidly follows.
• Skin perfusion:
  • Skin color: Pallor or cyanosis or mottling denotes decreased perfusion.
  • Temperature: Trunk and extremities should be examined simultaneously. When ambient temperature is warm, hands and feet should be warm. Cold hands and feet suggest fall in cardiac output.
  • CRT: Normal < 2 seconds, delayed means early shock.
• Brain perfusion assessed by features described in appearance i.e., changes in level of consciousness, pupil size, muscle tone and posturing.
• Renal perfusion:Urine output is useful in monitoring the child and evaluation of renal perfusion, although it may not be useful in initial assessment of critically ill child. At least 1 ml/kg/hour of urine output is normal.
• Pulse oximetry: To identify oxygen saturation, the 5th sign in acutely ill child.

Based on the physiologic status - stable, respiratory distress/failure, compensated/decompensated shock or cardio respiratory failure the child is managed further. He is re-evaluated after every intervention, for example, after a fluid bolus the child is assessed for improvement as indicated by:

• Improved capillary refill
• Stronger pulses
• Improved urine output
• Lower heart rate.

Bihar Pedicon 2005 - Conference Abstracts.Pediatric Oncall [serial online] 2005 [cited 01 June 2005];2. Available from:
http://www.pediatriconcall.com/fordoctor/Conference_abstracts/
approach_sickchild.asp