OXYGEN THERAPY - Background information
 
Oxygen
  • Oxygen (O2) is an odourless, colourless gas that makes up one fifth of the Earth's atmosphere
  • We breath in 20% oxygen
  • We breath out 16% oxygen
  • So the body needs only 4% oxygen to survive
The importance of O2
Oxygen is essential for life in that it combines chemically with Glucose to provide energy for the metabolic processes of the body, upon which we all depend to survive.
 
Contraindications
Oxygen therapy should never be withheld from any patient suffering from Hypoxia except for instances of Paraquat poisoning where the oxygen increases the toxicity of the poison.
 
Medical oxygen
  • Medical Oxygen is a Prescription Only Medicine (POM)
  • For ambulance purposes it is manufactured and stored in cylinders
  • Medical oxygen cylinders are white in colour with the words "Oxygen/O2" in black and grey printed on the cylinder body
Hypoxia
Every cell of the body must have a continuous supply of oxygen, but in cases of trauma or illness some organs of the body or the body as a whole may receive an inadequate amount. This lack of oxygen is termed hypoxia.
 
Oxygen therapy
By increasing the oxygen via oxygen therapy and therefore the amount of oxygen in the lungs we can reverse the effects of hypoxia on the brain, heart and other vital organs.
 
Signs and symptoms of hypoxia
  • Rapid, difficult or noisy breathing
  • Frothing at the mouth
  • Possible cyanosis (a late sign)
  • Dilated pupils
  • Congestion of neck & head veins
  • Deteriorating consciousness
  • Position of patient, i.e. bolt upright
  • Restless / fits
  • Rapid pulse
Conditions that benefit from oxygen therapy
  • Cardiac/respiratory arrest
  • Difficulty in breathing (Dyspnoea)
  • Cardiac conditions/CVA (Cerebro-Vascular Accident or stroke)/shock
  • Fitting/convulsions/fainting
  • Asthma attack/ COAD (Chronic Obstructive Airway Disease) patients
  • Chest & head injuries
  • Burns
  • Spinal & Pelvic injuries
  • Drowning/unconsciousness
  • Toxic inhalations
Causes of unconsciousness (Remember: FISH SHAPED)

  • Faint

  • Infection or Infantile convulsion

  • Shock

  • Head injury

  • Stroke

  • Heart attack

  • Asphyxia or Abnormal body temperature

  • Poison

  • Epilepsy

  • Diabetes
COPD (Chronic Obstructive Pulmonary Disease) See COPD & Hypoxic Drive

  • Asthma, chronic bronchitis, emphysema

  • Respiratory drive is on low levels of oxygen

  • High levels of oxygen may depress respiration

  • Hypoxic drive may be present

  • Administer no more than 24-28% Oxygen unless directed otherwise by paramedic or doctor
Administer with caution
Caution should be exercised with:

  • A neonate (newborn child) as after prolonged administration of high % oxygen can result

  • Patients whose main stimulus to breath is low oxygen levels (Hypoxic Drive). See COPD above.
Over-oxygenation
Any patient who is receiving oxygen therapy must be closely monitored. If their respiratory rate drops below 10 breaths per minute, oxygen therapy must be discontinued. If, after 30 seconds, their respiratory rate has not improved then assisted ventilations via bag & mask with reservoir bag attached and supplemental oxygen at a rate of 12 to 15 breaths per minute must be commenced.
 
Signs of over-oxygenation

  • Dry mouth

  • Dry tract linings

  • Rosy red cheeks
Reporting
Oxygen is a Prescription Only Medicine and we are required by law to report its use. We must record:

  • The concentration given, i.e. 28% @ 4 litres or 100% @ 15 litres

  • How long it was given

  • The effects it had on the patient
Assembling the equipment for use

  • Remove the manufacturer's seal on the cylinder (red parts)

  • Check for damage to outlet

  • Connect mask and tubing

  • Open the cylinder away from your face

  • Ensure flow meter is in the Off position
Use with care
All combustible materials that are combustible in air are ignited more easily and burn with a fiercer flame in the presence of pure oxygen. Oil, grease, sparks, flame or any other type of ignition source may also cause an explosion if it comes into contact with oxygen equipment. Oxygen is safe without a source of ignition.
NB When you use the AED on a patient ensure that the oxygen cylinder is not too close!
 
Masks & tubing

  • Oxygen masks allow oxygen delivered from the flow meter to be mixed with outside air

  • Most are made of clear plastic and are disposable

  • The % of O2 concentration selected for the patient is determined by the type of mask and the O2 flow rate

  • Usually the % concentration is shown on the outer wrapper of the mask, i.e. 100% or 28%.

  • Make sure you use the correct flow rate for the required concentration

  • Masks with oxygen reservoirs give the highest concentration of inspired oxygen

  • Keep face masks and tubes in their wrappers until required for use
Remember

  • Do not use the same disposable mask and tubing for more than one patient

  • Always explain to the patient what you are doing and why you are doing it
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