Paediatrics: Altered level of consciousness - Management

2021-03-09 12:00 AM

Consider the following if the cause of the coma is unknown.

Altered level of consciousness: management

Investigations

Consider the following if the cause of the coma is unknown.

Blood

  • FBC, clotting, and bleeding time.
  • Glucose, electrolytes, urea, liver function tests, ammonia, and lactate.
  • Save two extra tubes of clotted blood for storage in the laboratory.

Toxicology

  • Urine, blood, gastric aspirate for ingestions.
  • Serum lead and free erythrocyte protoporphyrin.

Acid-base 

Arterial blood gas.

Microbiology 

Blood and urine cultures.

Imaging

  • Cranial CT scan.
  • MRI particularly for posterior fossa or white matter lesions. Cranial imaging should only be performed if the child is well enough to leave the emergency department, i.e. a full assessment has been undertaken, and the child is stable, or intubated if GCS<9

Electroencephalography Standard EEG.

Lumbar puncture

Defer LP until a CT scan has been obtained if there are signs of raised ICP or focal neurology, and until after intubation if GCS<9. Examine CSF for microscopy, culture, glucose, and protein.

Meningitis

  • 20–20,000 white blood cells (WBC)/mm3with a polymorphonuclear neutrophil leucocyte predominance.
  • An elevated protein level >100mg/dL.
  • Low glucose <2mmol/L (or <50% of plasma level).

Encephalitis

  • 20–1000cells/mm3with lymphocyte predominance.
  • The presence of red blood cells (RBC) up to 500 cells/mm3suggests herpes simplex virus (HSV) infection.
  • CSF protein can be normal or mildly elevated.
  • Glucose is usually normal (770% of plasma level).

Monitoring

The form and type of monitoring will be dictated by the underlying cause of the patient’s state. Generally, after the initial evaluation, monitor hourly:

  • Vital signs, pupil reaction, fluid balance.
  • The GCS for neurological review—in those with GCS 9–11 a gastric tube and urinary catheter may be needed.

Treatment

Follow a standard protocol

  • ABC: the initial priority.
  • Glucose: whenever the cause of coma is not clearly obvious, 25%glucose (250–500mg/kg) should be given IV after a blood sample has been taken for laboratory blood glucose testing.
  • Specific therapies should be considered.

Antibiotics

Antimicrobial therapy is often given presumptively. The choice will depend on local epidemiology, public health, immunization, and antibiotic policy. In the comatose child, consider the following.

  • Age <4 weeks: group B streptococcus, Gram –ve bacteria, andListeriamonocytogenes: Recommend: ampicillin + aminoglycoside.
  • Infants 1–3 months: group B streptococcus, Gram-negative bacteria, Streptococcus pneumoniaNeisseria meningitides. Recommend: ampicillin + aminoglycoside/3rd generation cephalosporin.
  • >3 months: Streptococcus pneumoniaNeisseria meningitides.

Recommend: 3rd generation cephalosporin.

In the comatose older child where no CSF is available, a combination of antimicrobials to cover HSV, Streptococcus pneumonia, and Mycoplasma pneumonia infection is often prescribed.

  • Cefotaxime (IV 50mg/kg qds; maximum 12g/day).
  • Erythromycin (IV 10mg/kg qds).
  • Aciclovir (IV 10mg/kg, tds).