Management of Carbon Monoxide Poisoning

Causes

  • House Fire
  • Portable heaters
  • Ovens
  • Fires
  • Car exhaust
  • Cigarette Smoke
  • Suicide attempt

IF CO POISONING SUSPECTED TAKE IMMEDIATE HbCO LEVEL (cap,ven,art sample, Gas and EDTA Bottle) AND PUT ON 100% OXYGEN

History

  • History of exposure – time since exposure
  • Possible source
  • Co-morbidity – including cardiac or respiratory disease
  • Pregnancy
  • Cold weather/exposure
  • Other members of family exposed?

Clinical Features

General / Respiratory / Cardiovascular / Gastrointestinal / Psychiatry / Neurology
Flu-like
Malaise
Lethargy / Dyspnoea / Chest pain
Palpitations
Syncope / Nausea
Vomiting
Diarrhoea
Faecal/urinary incontinence / Confusion
Depression
Impulsiveness
Distractibility
Hallucinations
Confabulation
Agitation / Headache
Drowsy
Visual disturbance
Seizure
Memory
Gait Disturbance
Bizarre neuro symptoms

Coma

Examination

  • Immediate ABC
  • GCS

General / Resp / CVS /

Psychiatric

/

Neurology

Other injuries /  RR
Late  RR / pulse
Arrhythmias
 BP
BP / Amnesia
Test short term memory /

Full Examination

Conscious level
Hyperreflexia/
 plantars
Poor coordination
Blindness
Ataxia
Eyes - papilloedema

Signs of severe intoxication in Bold

Important points

  • Babies may just be floppy and poor feeding
  • Need to assess full neurological status including orientation, memory, visual-spatial awareness, concentration.
  • Be more cautious in pregnancy as increased risk to fœtus.

Investigations

Bloods

  • COHb if not already performed
  • FBC – mild leucocytosis
  • U+E/LFT
  • Glucose
  • CK/ LDH/Troponin – if HbCO level raised (CO can cause ischaemia/infarction)

CXR – pulmonary oedema

ECG – sinus tachycardia, arrhythmias

Consider

  • Paracetamol/salicylate levels if suicide attempt
  • Cyanide level if in fire

Management

Assess ABCD - glucose

If unable to maintain airway

  • Senior help
  • Intubate and Ventilate
  • Liaise with PICU

If concerns re raised ICP

(eg bradycardia, hypertension, variable/low GCS, pupillary abnormalities, abnormal posture )

  • Senior Help
  • Intubate and Ventilate
  • CT scan
  • Liaise with PICU

Correct Hypoglycaemia

Acidosis – corrects with O2 therapy no need to give sodium bicarbonate

Removal of Carbon Monoxide

CO level does not correlate well with severity of poisoning.

All children should be initially commenced on 100% oxygen.

Liaise with Poisons Information.

All symptomatic children should be admitted with regular review
Hyperbaric Oxygen

Use of hyperbaric oxygen therapy is controversial.

A recent Cochrane Review suggested that there is no evidence, in adults, to support use of Hyperbaric Oxygen for treatment of patients with CO poisoning.

National Poisons Information recommends that patients should be referred for HBO if there is easy and rapid access. They do not recommend it if transfer over long distance is required.

The British Hyperbaric Association currently suggests immediate discussion with Hyperbaric Unit if CO poisoning with clinical features below:

Any neurological abnormality

Cognitive impairment (memory)
Personality Change
Reduced GCS
Chest Pain – abnormal ECG, cardiac enzymes
Pregnancy
Loss of consciousness

If any of these features are present associated with Carbon Monoxide Poisoning liaise with Consultant on Call and PICU.

Follow up

Neurological features can become apparent 3-4 weeks post exposure. Parents need to be made aware of this on discharge. Follow-up may need to be arranged.

Public Health

Advised to contact Public Health

These may need to be informed to trace contacts, monitor levels etc.