LIQUID MEDICAL OXYGEN

Liquid Medical Oxygen is administered by vaporising the liquid to a gas at ambient temperatures and delivered for inhalation through the lungs. The major exception is when a metered supply is fed into the oxygenator of an extracorporeal circulation of a cardio-pulmonary by-pass system.

The need for medicinal oxygen should be determined by obtaining arterial blood gas values and/or by monitoring SpO2. The inspired oxygen should be titrated when used for long term oxygen therapy in patients with chronic hypoxic respiratory failure.

A SaO2/SpO2 between 88 and 92% is commonly assessed as adequate in patients with chronic obstructive pulmonary disease (COPD). A too liberal administration can increase the oxygen SaO2/SpO2 clearly above the patient's normal range, which may cause respiratory depression because of chemoreceptor insensitivity for CO2.

6 for instructions on how to use the Liquid Medical Oxygen homecare storage vessels for filling portable cylinders.

Oxygen toxicity can occur as manifested by: • Retrolenticular fibroplasia in premature infants exposed to Oxygen concentrations greater than 40%. • Convulsions appear after a few hours exposure at pressures of 3 atmospheres • Retrostemal soreness associated with coughing and breathing difficulties, made worse by smoking and exposure to cold air after breathing pure Oxygen at atmospheric pressure for several hours The most serious side effects that may occur are severe difficulty in breathing, so called respiratory distress syndrome.

g. some patients with chronic obstructive pulmonary disease (COPD) causing hypercapnia (frequency not known). Reporting of suspected adverse reactions Reporting suspected adverse reactions after authorisation of the medicinal product is important.

It allows continued monitoring of the benefit/risk balance of the medicinal product. uk/yellowcard.

Special care is needed when Liquid Oxygen is administered: • to neonates where the inspired concentration should not exceed 40% because of the risk of retrolenticular fibroplasia • to elderly chronic bronchitic patients in whom the inspired concentration should only be raised in stages of 1% and probably should not exceed 30% • in hyperbaric chambers in the management of conditions such as carbon monoxide poisoning, anaerobic infections and acute ischaemic disease.

Convulsions may occur at 3 atmospheres after a few hours. Oxygen levels should be monitored as required in the breath, blood and tissue to ensure that appropriate concentrations are not exceeded. In patients with reduced sensitivity for carbon dioxide pressure in arterial blood, high concentrations of oxygen may cause, respiratory depression subsequently causing carbon dioxide retention (hypercapnia), which in extreme cases can lead to carbon dioxide narcosis.

Where the patient has been exposed to agents which are toxic to the lungs, such as Paraquat, the use of gases containing more than 21% oxygen should be avoided. Liquid Medical Oxygen is non-flammable but strongly supports combustion and should not be used near sources of ignition.

Smoking should be prohibited when using Liquid Medical Oxygen. Under no circumstances should oils or grease be used to lubricate any part of the Medical Liquid Oxygen storage vessel or the associated equipment used to deliver the gas to the patient.

Where moisturising creams are required for use with a facemask or in nasal passages. oil based creams should not be used. Check that hands are clean and free from any oils or grease. Where alcohol gels are used to control microbiological cross-contamination ensure that all alcohol has evaporated before handling Liquid Medical Oxygen vessels or equipment.

Care is needed when handling and using Liquid Medical Oxygen vessels. Always use vessels upright unless otherwise instructed. Liquid Medical oxygen is a cryogenic liquid with a temperature of -183oC at ambient pressure. The medical oxygen generated by vapourising the Liquid Medical Oxygen will also be very cold and should be warmed to ambient temperature using appropriate equipment prior to administration to the patient.

Transient exposure to very cold gas can provoke attacks of asthma in susceptible subjects and prolonged breathing of cold gas may damage lung tissue. Never directly touch any of the cold parts of the vessel or associated equipment or allow liquid oxygen to come into contact with your skin as this could cause a cold burn.

If this occurs immerse affected skin in tepid water and seek medical treatment. Use appropriate Personal Protective Equipment (PPE) and follow the medical equipment instructions for use when using or handling Liquid Medical Oxygen. Clothing and materials may become saturated with oxygen if it is exposed to a Liquid Medical Oxygen leak or an excessive gas release from the Liquid Medical Oxygen vessel.

If clothing becomes saturated the wearer should be advised to walk around in a well- ventilated area for at least 15 minutes, keeping well away from naked flames or sources of ignition. Ensure that the Liquid Medical Oxygen vessel is stored in a well ventilated area so that any leak of liquid or gas will naturally disperse over time.

There are no absolute contra-indications to the use of Oxygen, but the inspired concentration should be limited in the case of premature infants and those patients with chronic bronchitis and emphysema.