Lethargy and irritability in a child

Lethargy is abnormal drowsiness, reduced alertness and activity, poor responsiveness to stimulation and diminished interaction. Irritability is excessive fretfulness, a low threshold for crying, and difficulty being comforted. They often occur together and may alternate in the same child.

Together they are among the most important nonspecific signs of serious illness in infants and young children. Causes include sepsis, meningitis, encephalitis, raised intracranial pressure, hypoglycaemia, metabolic disease, severe dehydration, shock, severe anaemia, cerebral malaria, intoxication and non accidental injury.

A child who is both lethargic and irritable is at particular risk of meningitis or intracranial disease. This includes paradoxical irritability, where the child cries when handled and is quiet when left alone.

Definitions

• Lethargy: a state of drowsiness in which the child is difficult to arouse, is not interested in the environment, and shows little spontaneous activity.
• Stupor: a state in which the child can be roused only by vigorous or painful stimuli.
• Coma: a Glasgow Coma Scale score of 8 or under (or an AVPU level of P or U).
• Irritability: an exaggerated response to normal stimuli, with inconsolable crying.
• Paradoxical irritability: increased crying with handling or movement, quieter when still.
• Altered level of consciousness: any decrease in alertness and awareness.
• AVPU scale: grades a child as Alert, responding to Voice, responding to Pain, or Unresponsive.
• Blantyre coma score (motor, verbal and eye movements, maximum 5): used in malaria endemic settings. A score of 2 or under indicates coma.

Classification by cause

• Infection: bacterial sepsis, meningitis (pneumococcus, meningococcus, Haemophilus, group B Streptococcus, Escherichia coli, Listeria, tuberculosis), encephalitis (herpes simplex virus, enterovirus, arbovirus), cerebral malaria, urinary tract infection, pneumonia, typhoid, severe gastroenteritis, brain abscess, and toxic shock syndrome.
• Metabolic and endocrine: hypoglycaemia, diabetic ketoacidosis, hyponatraemia or hypernatraemia, hypocalcaemia, hypothyroidism, adrenal insufficiency, inborn errors of metabolism (urea cycle defects, organic acidaemias, fatty acid oxidation defects), hyperammonaemia, uraemia, liver failure, and Reye like illness.
• Haemodynamic and respiratory: shock (septic, hypovolaemic, cardiogenic), dehydration, severe anaemia, hypoxia, hypercapnia, heart failure, arrhythmia, and carbon monoxide poisoning.
• Neurological: seizures and postictal state, nonconvulsive status epilepticus, raised intracranial pressure, hydrocephalus, shunt blockage, intracranial haemorrhage, subdural haematoma, head injury, brain tumour, stroke, acute disseminated encephalomyelitis, and autoimmune encephalitis.
• Toxic: ingestion of drugs (opioids, benzodiazepines, antihistamines, clonidine, tricyclic antidepressants, sulphonylureas, alcohol, paracetamol, iron, salicylates), plants, household products, and organophosphates, plus lead and carbon monoxide.
• Trauma and abuse: abusive head trauma, intra abdominal injury, fractures, and neglect.
• Gastrointestinal and renal: intussusception (lethargy between bouts of pain), volvulus, haemolytic uraemic syndrome, and hepatic failure.
• Haematological: severe anaemia, sickle cell crisis, and malignancy.
• Psychosocial: depression, anxiety, fatigue from sleep deprivation, neglect, and emotional distress.
• Benign: tiredness, post vaccination fatigue, mild viral illness, teething, and normal sleepiness.

Epidemiology.

• Altered consciousness accounts for under 1% of paediatric emergency visits. Lethargy and irritability are common features of serious bacterial infection, appearing in most infants with meningitis.
• Bacterial meningitis occurs in about 1 in 1,000 to 1 in 10,000 children each year. Rates are higher in sub-Saharan Africa and in children under 1 year.
• Malaria is the commonest cause of coma in children in endemic regions. Cerebral malaria has a mortality of 15% to 20% with treatment.
• Hypoglycaemia is common in sick, malnourished children and neonates.
• Poisoning is a frequent cause of toddler drowsiness.
• Abusive head trauma presents with lethargy, irritability and vomiting. It is missed in a third of cases at first presentation.

Mechanisms. Consciousness depends on the reticular activating system and both cerebral hemispheres. Lethargy results from diffuse cortical or brainstem dysfunction due to toxins, metabolic derangement, hypoxia, ischaemia, raised intracranial pressure, inflammatory cytokines, and seizure activity. Irritability reflects meningeal inflammation, raised intracranial pressure, pain, hunger, hypoglycaemia, withdrawal, or cortical hyperexcitability.

Key distinctions.

• Fever, rash, neck stiffness or bulging fontanelle with drowsiness and irritability points to meningitis.
• Fever with seizures, focal signs, and confusion in a child from a malaria region points to cerebral malaria.
• A previously well toddler with sudden drowsiness, miosis or pinpoint pupils, and slow breathing points to opioid or clonidine poisoning.
• Drowsiness with deep rapid breathing, vomiting and abdominal pain points to diabetic ketoacidosis or salicylate poisoning.
• Poor feeding, vomiting and lethargy in the first week of life with acidosis and a high ammonia point to an inborn error of metabolism.
• Drowsiness with vomiting after a fall, bruises, and retinal haemorrhages points to abusive head trauma.
• Intermittent pallor, pain with drawing up of legs, and then lethargy points to intussusception.
• Drowsiness with pallor and jaundice points to haemolysis.
• Drowsiness with persistent vomiting and a rising head circumference points to hydrocephalus.

History

• Onset and course of the change: sudden or gradual, hours or days, progressive or fluctuating, and how the child differs from usual behaviour and interaction.
• Associated symptoms: fever, headache, vomiting, neck pain or stiffness, photophobia, rash, seizure, diarrhoea, polyuria and polydipsia, abdominal pain, cough, difficulty breathing, jaundice, pallor, limb weakness, reduced feeding, and reduced urine output.
• Injury: falls, head trauma, abuse concern, or unexplained bruises.
• Ingestion: access to medicines (parental, grandparental or sibling), household chemicals, plants, alcohol, cannabis edibles, button batteries, and carbon monoxide sources (heaters, charcoal, generators). Ask about breast milk exposure to maternal drugs.
• Travel and exposure: malaria area, sick contacts, tuberculosis contact, animal bites, tick exposure, and swimming in fresh water.
• Immunisation status (Haemophilus influenzae type b, pneumococcal, meningococcal, measles, BCG).
• Past history: diabetes, epilepsy, shunts, cardiac, renal or metabolic disease, immunodeficiency, HIV, sickle cell disease, and previous similar episodes.
• Perinatal history in infants: gestation, birth complications, jaundice, maternal infection, and family history of metabolic disease or unexplained infant death.
• Development and diet: feeding pattern, weight loss, fasting, and recent change in formula.
• Medicines and allergies, family and social context, safeguarding concerns, and parental perception ("not himself").

Examination

• Assess airway, breathing, circulation, disability and exposure first. Measure temperature, heart rate, respiratory rate, blood pressure, oxygen saturation, capillary refill, glucose, and weight.
• Level of consciousness with AVPU and the Glasgow Coma Scale (paediatric version) or Blantyre coma score. Record pupils (size, reactivity), eye movements, posture (decorticate, decerebrate), response to pain, and tone.
• Look for meningism (neck stiffness, Kernig and Brudzinski signs unreliable under 18 months), bulging or sunken fontanelle, head circumference, and cranial nerve signs.
• Signs of raised intracranial pressure (Cushing triad: bradycardia, hypertension, irregular breathing; papilloedema is a late and unreliable sign in infants), and signs of brainstem herniation (unequal or fixed pupils, abnormal posture).
• Skin: petechiae and purpura (non blanching rash), pallor, jaundice, cyanosis, mottling, bruising, burns, and dehydration.
• Breathing pattern: Kussmaul breathing (acidosis), slow respirations (opioids), Cheyne-Stokes.
• Odours: ketones (acetone), alcohol, and organophosphate.
• Heart: murmur, gallop, hepatomegaly, femoral pulses. Abdomen: distension, tenderness, masses, organomegaly.
• Eyes: retinal haemorrhages (abuse), papilloedema, nystagmus, and ophthalmoplegia.
• Dehydration assessment and signs of shock.
• Cardiovascular: heart rate for age, capillary refill time of 3 seconds or more, cool peripheries, weak pulses, and hypotension (late).
• Whole body search for injury, including scalp, behind ears, mouth and genitalia, and measure the head circumference.

Red flags

• Reduced consciousness: AVPU of V, P or U, or a Glasgow Coma Scale score under 15, or failure to recognise parents.
• Seizure or prolonged postictal state (over 1 hour), or focal neurological signs.
• Fever with non blanching rash, neck stiffness, bulging fontanelle, or photophobia.
• Shock (tachycardia, prolonged capillary refill, mottling, cool extremities, weak pulses, hypotension).
• Respiratory distress, apnoea, or abnormal breathing pattern.
• Hypoglycaemia (glucose under 3.0 mmol/L; under 2.6 mmol/L in neonates).
• Age under 3 months with lethargy or irritability (high risk of sepsis, meningitis, herpes simplex virus infection, metabolic disease, and abuse).
• Unexplained bruising, fractures, retinal haemorrhages, or inconsistent history (abusive head trauma).
• Sudden onset after ingestion (suspected poisoning), or pinpoint or dilated pupils.
• Persistent vomiting with headache, enlarging head or sunset eyes (raised intracranial pressure).
• Recent travel to or residence in a malaria area, with fever.
• Severe pallor with tachycardia and breathlessness (severe anaemia).
• Dehydration, polyuria and polydipsia, or Kussmaul breathing.
• Poor feeding, vomiting and drowsiness in the first weeks of life (metabolic disease or sepsis).
• Hypothermia (under 36.0 degrees Celsius) or hyperthermia (over 40.0 degrees Celsius).
• Immunosuppression, HIV, sickle cell disease, ventriculoperitoneal shunt, or recent neurosurgery.
• Head injury with vomiting, drowsiness or seizure.

Special groups

• Neonates and young infants: poor feeding, hypotonia, hypothermia and apnoea are the main manifestations. Exclude sepsis, meningitis, herpes simplex virus, hypoglycaemia and metabolic disease.
• Toddlers: ingestion, trauma, infection and seizures are the commonest.
• School age children and adolescents: infection, diabetic ketoacidosis, intoxication (alcohol, drugs), head injury, depression, and autoimmune encephalitis.
• Children with neurodisability: pain, shunt malfunction, seizures, and medication effects.
• Malnourished children: hypoglycaemia, hypothermia, sepsis, and electrolyte disturbance; lethargy is a sign of severe malnutrition and an indication for admission.
• Region specific: cerebral malaria, bacterial meningitis (meningitis belt), tuberculous meningitis, HIV encephalopathy, typhoid encephalopathy, severe anaemia, neonatal tetanus, hyperbilirubinaemia, kernicterus, and snake bite.

Infectious

• Sepsis and septic shock, bacterial meningitis, viral meningitis and encephalitis (herpes simplex virus, enteroviruses, arboviruses, rabies in exposed children), tuberculous meningitis, cryptococcal meningitis in HIV, cerebral malaria, severe malaria with anaemia, typhoid, brain abscess, subdural empyema, and toxic shock syndrome.
• Pneumonia, pyelonephritis, osteomyelitis, myocarditis, and severe gastroenteritis.

Metabolic and endocrine

• Hypoglycaemia, diabetic ketoacidosis, hyperosmolar state, hyponatraemia, hypernatraemia, hypocalcaemia, hypothyroidism, adrenal crisis, inborn errors (urea cycle disorders, organic acidaemias, fatty acid oxidation defects, galactosaemia, mitochondrial disease), hepatic encephalopathy, uraemia, and hyperammonaemia.

Neurological and structural

• Seizure and postictal state, nonconvulsive status epilepticus, intracranial haemorrhage, subdural haematoma, hydrocephalus and shunt failure, brain tumour, cerebral venous thrombosis, stroke, acute disseminated encephalomyelitis, autoimmune encephalitis, and acute cerebellar ataxia.
• Migraine and hemiplegic migraine in older children.

Toxic

• Opioids, benzodiazepines, antihistamines, clonidine, tricyclic antidepressants, antipsychotics, sulphonylureas, salicylates, paracetamol, iron, alcohol, cannabis, carbon monoxide, organophosphates, lead, and plant poisons.

Cardiorespiratory and haematological

• Shock (septic, hypovolaemic, cardiogenic, anaphylactic), heart failure, supraventricular tachycardia, myocarditis, severe asthma with hypercapnia, severe anaemia, haemolytic uraemic syndrome, sickle cell crisis, methaemoglobinaemia, and leukaemia.

Trauma and non accidental injury

• Abusive head trauma, concussion, intracranial bleed, intra abdominal injury, and fractures.

Gastrointestinal

• Intussusception, volvulus, appendicitis with peritonitis, and liver failure.

Psychological and functional

• Depression, anxiety, conversion disorder, sleep deprivation, neglect, and normal tiredness.

Step 1. Resuscitate. Open the airway, give oxygen, support breathing, obtain intravenous or intraosseous access, and treat shock. Check capillary glucose at once in every lethargic or irritable child, and treat hypoglycaemia immediately. Assess consciousness with AVPU.

Step 2. First line tests (all children with altered consciousness or sepsis concern)

• Capillary glucose, venous blood gas with lactate and base excess, full blood count, C-reactive protein, urea, creatinine, electrolytes (sodium, potassium, chloride, bicarbonate), calcium, magnesium, phosphate, liver tests, ammonia, and blood culture.
• Urinalysis, urine culture (catheter or suprapubic in infants), and urine ketones.
• Malaria rapid test and blood film in anyone from or recently in an endemic area (parasite density, glucose, haemoglobin).
• Toxicology: paracetamol and salicylate levels, urine drug screen, blood alcohol, and carboxyhaemoglobin by co-oximetry when poisoning is possible.
• Pregnancy test in adolescent girls.
• ECG (arrhythmia, QTc, tricyclic toxicity with QRS over 100 ms).

Step 3. Targeted tests

• CT head (non contrast) when there is trauma, focal signs, raised intracranial pressure, an unexplained decreased level of consciousness, or concern for abuse.
• Do CT before lumbar puncture if signs of raised pressure exist.
• Magnetic resonance imaging for encephalitis, stroke, venous thrombosis, and tumour.
• Lumbar puncture (when safe) for suspected meningitis or encephalitis: opening pressure, cell count, protein, glucose with paired blood glucose, Gram stain, culture, polymerase chain reaction (herpes simplex virus, enterovirus, parechovirus, meningococcus and pneumococcus), cryptococcal antigen, tuberculosis tests.
• Do not delay antibiotics if the lumbar puncture is delayed.
• Contraindications to lumbar puncture: shock, coagulopathy, raised intracranial pressure signs, respiratory compromise, focal neurological signs, local skin infection, and seizure not controlled.
• Electroencephalogram for unexplained or fluctuating consciousness, suspected nonconvulsive status, or encephalitis.
• Metabolic tests in infants and children: ammonia, lactate, plasma amino acids, urine organic acids, acylcarnitine profile, ketones and reducing substances.
• Take a critical sample at the time of hypoglycaemia (insulin, cortisol, growth hormone, beta-hydroxybutyrate, free fatty acids).
• Cranial ultrasound in infants with an open fontanelle (haemorrhage, hydrocephalus), skeletal survey, ophthalmology review for retinal haemorrhages, and child protection assessment when abuse is suspected.
• Thyroid function, cortisol, and adrenal tests as indicated.
• Echocardiography, chest radiograph and troponin for suspected cardiac disease.
• Abdominal ultrasound for intussusception or obstruction.
• Blood film (sickle cells, fragments, parasites), reticulocytes, direct antiglobulin test, and lactate dehydrogenase for haemolysis.
• Autoimmune encephalitis antibodies (serum and cerebrospinal fluid) for subacute presentations.

Step 4. Interpretation.

• A glucose under 3.0 mmol/L in a lethargic child is treated as the cause until proved otherwise.
• Anion gap acidosis with high lactate suggests shock, sepsis, or metabolic disease. Ketones with high glucose confirm ketoacidosis.
• Hyperammonaemia (over 100 micromoles/L in a neonate, over 50 in an older child) with respiratory alkalosis suggests urea cycle disorder.
• Cerebrospinal fluid with neutrophils, high protein and low glucose supports bacterial meningitis. Lymphocytes with normal glucose suggests viral meningitis. Low glucose with lymphocytes suggests tuberculosis.
• A positive malaria test in a child with coma does not exclude another cause, so also treat or exclude meningitis.
• A normal CT scan does not exclude encephalitis, early infarction, or diffuse axonal injury.

Limits. Infants may have no meningism, no fever, and subtle neurological signs. Tests may be normal in early sepsis. Toxicology screens do not detect all drugs. Parents may not report ingestion. Lumbar puncture may be unsafe. Treatment must not wait for confirmation when sepsis or meningitis is suspected.

Immediate (any child with lethargy and a red flag)

• Airway: position, suction, jaw thrust, airway adjuncts, and intubate for GCS 8 or under, loss of airway protection, or respiratory failure.
• Breathing: oxygen at 10 to 15 L/min by non rebreather mask to keep saturation 94% to 98%, and assisted ventilation if needed.
• Circulation: intravenous or intraosseous access. In shock give an isotonic crystalloid 10 mL/kg (up to 20 mL/kg) bolus. Reassess after each bolus.
• Give 10 mL/kg over 30 to 60 minutes in malnourished children and suspected severe malaria with anaemia.
• Start adrenaline 0.05 to 0.3 micrograms/kg/minute if shock continues after 40 to 60 mL/kg.
• Glucose: if under 3.0 mmol/L (under 2.6 mmol/L in neonates) give 10% dextrose 2 mL/kg intravenously (up to 5 mL/kg). Recheck in 15 to 30 minutes, then infuse 10% dextrose at maintenance rate (5 to 8 mg/kg/minute for infants).
• If there is no access, give glucagon 0.03 mg/kg (maximum 1 mg) intramuscularly. For persistent hypoglycaemia add hydrocortisone 2.5 mg/kg intravenously.
• Seizure: lorazepam 0.1 mg/kg intravenously (maximum 4 mg), or midazolam 0.3 mg/kg buccal (maximum 10 mg) or 0.2 mg/kg intranasal. Repeat once after 5 to 10 minutes.
• Then give levetiracetam 40 to 60 mg/kg (maximum 4.5 g) or phenytoin 20 mg/kg intravenously (phenobarbital 20 mg/kg in neonates).
• Temperature: warm if hypothermic, cool if over 40.0 degrees Celsius.
• Monitor continuously: heart rate, oxygen saturation, blood pressure, glucose, GCS or AVPU every 15 minutes.

Suspected sepsis or meningitis (start within 1 hour; do not wait for imaging or lumbar puncture)

• Ceftriaxone 80 mg/kg intravenously (maximum 4 g) once daily, or 50 mg/kg every 12 hours, in infants over 1 month and children.
• In neonates under 28 days: ampicillin 100 mg/kg every 6 hours (for meningitis) with cefotaxime 50 mg/kg every 6 to 8 hours (every 12 hours in the first week) or gentamicin 5 mg/kg every 24 hours. Avoid ceftriaxone in jaundiced neonates.
• Add vancomycin 15 mg/kg every 6 hours (maximum 500 mg for each dose when levels are not available) where penicillin resistant pneumococci are present.
• Dexamethasone 0.15 mg/kg (maximum 10 mg) intravenously every 6 hours for 4 days, started before or with the first antibiotic dose, in children over 3 months with suspected bacterial meningitis.
• Aciclovir 10 mg/kg intravenously every 8 hours in children over 3 months (20 mg/kg every 8 hours in neonates and infants under 3 months) for suspected encephalitis. Continue until herpes simplex virus is excluded (usually 14 to 21 days if confirmed).
• Duration for bacterial meningitis: meningococcus 5 to 7 days, Haemophilus 7 days, pneumococcus 10 to 14 days, group B Streptococcus and Listeria 14 to 21 days, Gram negative bacilli 21 days.
• Add ampicillin or amoxicillin 50 mg/kg every 6 hours for Listeria in infants under 3 months, immunosuppressed children, and the elderly.

Cerebral malaria and severe malaria

• Artesunate 2.4 mg/kg intravenously (3 mg/kg for each dose in children under 20 kg) at 0, 12 and 24 hours then once daily until oral therapy is possible (minimum 24 hours), followed by a full 3 day oral artemisinin combination course.
• Check glucose every 4 hours and treat hypoglycaemia. Treat seizures.
• Give blood transfusion for severe anaemia (haemoglobin under 5 g/dL, or under 7 g/dL with parasitaemia over 10%): packed red cells 10 mL/kg (or whole blood 20 mL/kg) over 3 to 4 hours. Avoid fluid overload.
• Do not give corticosteroids, mannitol or routine anticonvulsant prophylaxis for cerebral malaria.

Raised intracranial pressure

• Head midline and elevated 30 degrees, oxygen, treat seizures and fever, maintain normal sodium, maintain systolic blood pressure, and avoid hypotonic fluids.
• 3% hypertonic saline 3 to 5 mL/kg intravenously over 10 to 20 minutes (target sodium 145 to 155 mmol/L), or mannitol 0.25 to 0.5 g/kg intravenously over 20 minutes (avoid in shock).
• Use brief hyperventilation only for impending herniation. Refer urgently to neurosurgery, with external drainage for hydrocephalus.
• Dexamethasone 0.25 to 0.5 mg/kg (maximum 10 mg) intravenously every 6 hours for vasogenic oedema from tumour.

Diabetic ketoacidosis

• Give a fluid bolus only if shocked (10 mL/kg 0.9% sodium chloride).
• Otherwise replace the deficit (usually 5% to 10%) with 0.9% sodium chloride with potassium chloride 40 mmol/L evenly over 48 hours, plus maintenance.
• Start insulin 0.05 to 0.1 units/kg/hour 1 hour after the start of fluids. Add 5% dextrose when glucose is under 14 mmol/L.
• Monitor glucose hourly, and electrolytes and ketones every 2 to 4 hours. Monitor neurological status for cerebral oedema (headache, falling consciousness, bradycardia, hypertension).
• Treat suspected cerebral oedema with mannitol 0.5 to 1 g/kg or hypertonic saline 3% 2.5 to 5 mL/kg.

Poisoning

• Opioids, clonidine: naloxone 0.01 mg/kg (maximum 0.4 mg for each bolus at first; up to 2 mg) intravenously, intramuscularly or intranasally (0.1 mg/kg to maximum 2 mg), repeated every 2 to 3 minutes.
• For naloxone, use an infusion at two thirds of the effective hourly dose when needed. Observe for at least 6 hours for long acting opioids (methadone, buprenorphine) because of risk of recurrence.
• Benzodiazepines: supportive; flumazenil is avoided because of seizure risk in mixed ingestion.
• Paracetamol: acetylcysteine 150 mg/kg intravenously over 1 hour, then 50 mg/kg over 4 hours, then 100 mg/kg over 16 hours, when level is over the treatment line or the amount is uncertain or large (over 150 mg/kg).
• Salicylate: sodium bicarbonate 1 to 2 mmol/kg intravenously to alkalinise urine, haemodialysis for severe toxicity.
• Tricyclic antidepressants with QRS over 100 ms: sodium bicarbonate 1 to 2 mmol/kg intravenously, repeated, and treat seizures with benzodiazepines.
• Sulphonylureas: dextrose, then octreotide 1 microgram/kg subcutaneously every 6 hours.
• Carbon monoxide: 100% oxygen by non rebreather mask, hyperbaric oxygen in selected cases.
• Organophosphates: atropine 0.02 mg/kg intravenously, doubling every 5 minutes until secretions dry, with pralidoxime 25 to 50 mg/kg.
• Activated charcoal 1 g/kg (maximum 50 g) within 1 hour for ingestion of a toxic dose with an intact airway; contact the poisons service early.

Treatment by other causes

• Hyponatraemic seizures or sodium under 125 mmol/L with symptoms: 3% sodium chloride 2 to 3 mL/kg over 10 to 20 minutes, repeated up to twice, to raise sodium by 4 to 6 mmol/L. Limit correction to 8 to 10 mmol/L in 24 hours.
• Hypocalcaemia: calcium gluconate 10% 0.5 mL/kg (maximum 20 mL) intravenously over 10 to 30 minutes with ECG monitoring.
• Adrenal crisis: hydrocortisone 4 mg/kg (maximum 100 mg) intravenously, then 1 mg/kg every 6 hours, fluids, and glucose.
• Suspected inborn error: stop protein, 10% dextrose with electrolytes at 1.5 times maintenance, and early metabolic specialist advice.
• For hyperammonaemia over 150 micromoles/L: sodium benzoate and sodium phenylbutyrate (or phenylacetate) with arginine as directed by the metabolic team, and haemofiltration for severe cases.
• Severe anaemia: transfusion of packed red cells 10 mL/kg over 3 to 4 hours (slower in heart failure, with furosemide 1 mg/kg), and treat the cause.
• Intussusception: fluids, analgesia, enema reduction or surgery.
• Heart failure or supraventricular tachycardia: treat the underlying disorder, with adenosine 100 micrograms/kg rapid bolus (to 300 micrograms/kg).
• Abusive head trauma or suspected abuse: neurosurgical care as needed, skeletal survey, ophthalmology review, social care referral, document carefully, and keep the child in hospital until safe.
• Febrile or postictal drowsiness: monitor; if the child does not return to baseline in 1 hour, look for another cause.
• Viral illness with mild irritability and normal examination: fluids, paracetamol 15 mg/kg every 4 to 6 hours, and review.
• Psychological: sleep hygiene, supportive counselling, and child and adolescent mental health referral.

Special populations

• Neonates: low threshold for full sepsis work up including lumbar puncture, and for empirical aciclovir.
• Malnourished children: hypoglycaemia and hypothermia are common; feed early, give antibiotics, and use cautious fluids.
• HIV: add tuberculosis, cryptococcus, and Pneumocystis to the differential.
• Sickle cell disease: fever with lethargy needs urgent antibiotics and consideration of stroke and sequestration.
• Shunt patients: shunt series and neurosurgical review.
• Renal and hepatic impairment: adjust doses (gentamicin, aciclovir).

Monitoring. Level of consciousness (AVPU or GCS and Blantyre score), pupils, heart rate, blood pressure, oxygen saturation, temperature, glucose (hourly in hypoglycaemia, every 4 hours in malaria), electrolytes, fluid balance, seizure activity, and neurological observations. Repeat examination for new signs.

Referral and escalation. Paediatric intensive care for GCS 8 or under, shock not responding to 40 to 60 mL/kg, respiratory failure, refractory seizures, and raised intracranial pressure. Neurology, neurosurgery, infectious diseases, endocrinology, metabolic medicine, toxicology and poisons service, haematology and child protection teams as indicated.

Admission criteria. Any child with reduced consciousness, red flags, suspected meningitis, sepsis, shock, hypoglycaemia, seizure with incomplete recovery, poisoning, suspected abuse, metabolic disease, severe anaemia, dehydration, and infants under 3 months with lethargy.

Discharge and follow up. Discharge only after return to normal alertness, feeding and activity, stable observations, normal glucose, and a clear cause or satisfactory observation period (at least 4 to 6 hours for mild cases). Give written advice.

Safety netting. Advise return for drowsiness or difficulty waking, floppiness, fever with rash, stiff neck, bulging fontanelle, persistent vomiting, seizure, severe headache, fast or noisy breathing, pallor or jaundice, no urine in 8 hours, poor feeding, a high pitched cry, or worsening irritability.