Medical Oxygen
SUMMARY OF PRODUCT CHARACTERISTICS
1 NAME OF THE MEDICINAL PRODUCT
Liquid Medical Oxygen
2. QUALITATIVE AND QUANTITATIVE COMPOSITION
Liquid Medical Oxygen is supplied as a medical gas as a refrigerated liquid gas. It is either supplied as a bulk medical gas by transfer from a vacuum insulated mobile tanker or as a liquid in portable liquid cylinders.
The Liquid Medical Oxygen is supplied to the following specification:
Medical Oxygen Purity
Maximum Impurity Levels
Carbon Monoxide Carbon Dioxide Moisture
Acidity / Alkalinity Oxidising Substances 99.5% (min)
5 vpm 300 vpm 50 vpm
To pass Oxygen EP test To pass Oxygen EP test
Bulk Liquid Medical Oxygen is supplied to customers in vacuum insulated mobile tankers fitted with stainless steel tanks and transferred to the customer's tank via a stainless steel flexible hose fitted with product specific couplings. The customer storage tank is also a vacuum insulated stainless steel or Aluminium tank, fitted with brass valves and copper interconnecting pipework. The customer storage tanks have an equivalent gas content normally of up to 20,000 litres and are installed to the specifications detailed in HTM 2022.
The portable liquid cylinders used for supplying Liquid Medical Oxygen are manufactured in stainless steel, with stainless steel valves and components. All materials used in the construction of the tanks and valves are compatible with Liquid Oxygen in terms of reacting or suitability with respect to auto ignition.
Liquid Cylinder and Valve Details
|
Cylinder Size |
Gas Content (litres) |
Cylinder Construction |
Valve Outlet |
Valve Constructio n |
|
DLC 1 |
1032 |
Stainless Steel Vacuum Insulated |
Product Specific Filling Connector Fir Tree Outlet |
Stainless Steel |
|
DLC 30 |
28,800 |
Stainless Steel Vacuum Insulated |
Product Specific Filling Connector Fir Tree Outlet |
Stainless Steel |
|
DLC 37 |
31,820 |
Stainless Steel Vacuum Insulated |
Product Specific Filling Connector Fir Tree Outlet |
Stainless Steel |
|
DLC 200 |
148,000 |
Stainless Steel Vacuum Insulated |
Product Specific Filling Connector Product Specific Outlet |
Stainless Steel |
3. PHARMACEUTICAL FORM
Liquified Medical Gas
4. CLINICAL PARTICULARS
4.1 Therapeutic indications
Liquid Medical Oxygen is widely used:
• in clinical practice to provide a basis for most modem anaesthetic techniques including pre- and post-operative management.
• to restore the tissue Oxygen tension towards normal by improving Oxygen availability in a wide range of conditions such as:
• Cyanosis of recent origin as a result of cardio-pulmonary disease
• Surgical trauma, chest wounds and rib fracture
• Shock, severe haemorrhage and coronary occlusion
• Carbon monoxide poisoning
• Hyperpyrexia
• Major trauma, ie road traffic accidents and gunshot wounds
• in the management of sudden cardiac and respiratory arrest, whether drug induced or traumatic
• in the resuscitation of the critically ill, when the circulation is impaired
• in neo-natal resuscitation
In all cases, the Liquid Medical Oxygen is vaporised to a compressed gas at ambient conditions before being administered to the patient.
4.2 Posology and method of administration
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.
4.3 Contraindications
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.
4.4 Special warnings and precautions for use
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.
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/cylinder 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 cylinders or equipment.
Care is needed when handling and using Liquid Medical Oxygen cylinders.
4.5 Interaction with other medicinal products and other forms of interaction
The pharmacokinetic activity of Oxygen is modified by changes in blood carbon dioxide tension, but this has little clinical significance
The use of higher levels of oxygen can increase the risk of pulmonary toxicity in patients who have been administered Bleomycin, Amiodarone and Nitrofurantoin or similar antibiotics. In these cases oxygen should be administered with caution and at levels kept as low as possible.
4.6 Pregnancy and lactation
Oxygen does not adversely affect pregnancy and lactation.
4.7 Effects on ability to drive and use machines
In normal circumstances, Oxygen does not interfere with the conscious level but patients who require continuous Oxygen support are obviously not fit either to drive or to operate machinery.
4.8 Undesirable effects
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
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. Healthcare professionals are asked to report any suspected adverse reactions via The Yellow Card System www.mhra.gov.uk/yellowcard
4.9 Overdose
As detailed above in 'Undesirable Effects'.
PHARMACOLOGICAL PROPERTIES
5.
5.1 Pharmacodynamic properties
The characteristics of Oxygen are:
odourless, colourless gas
molecular wei ght 32
boiling point -183.1 °C (at 1 bar)
Density 1.355 kg/m3 (at 15 °C)
Oxygen is present in the atmosphere at 21% and is an absolute necessity for life.
The basal Oxygen consumption in man is about 250mm/min for a body surface of 1.8m2. It
is reduced by about 10% during anaesthesia and natural sleep and by about 50% for a 10°C fall in body temperature.
Alveolar air contains about 14% Oxygen (105mm Hg) and the arterial blood has an Oxygen tension of 97mm Hg. The difference, known as the alveolar-arterial Oxygen tension gradient, increases with age. The difference may be as great as 30mm Hg in a healthy, elderly individual.
Oxygen in the blood is mostly combined with haemoglobin. 1.34ml per 9ml to give a maximum capacity of 20ml per 100ml of blood. A small amount, 0.3ml, exists in solution in the same volume of blood.
The concept of Oxygen availability first described by Richards in 1943 and later elaborated by Freeman and Nunn has been used to quantify the amount of Oxygen available to the body. It can be expressed as the product of the cardiac output and the Oxygen content of the blood.
Available Oxygen = (cardiac output) x Hb conc x 1.34 x (% saturation) Substituting normal values:
Available Oxygen = (5000ml) 15/100 x 1.34 x 95/100 = 950ml
The average healthy individual with a basal Oxygen consumption has no more
than four minutes supply of Oxygen in the blood.
5.2 Pharmacokinetic properties
The uptake of Oxygen by the blood in the lungs and discharge to the tissues is determined by the Oxygen dissociation curve. The characteristic sigmoid shape ensures that, at tensions between 40 and 15mm Hg, the Oxygen carried in the blood from the lungs can be readily given up to the tissues.
The uptake from the lungs is rapid, because blood flow through the capillaries, where exchange takes place, occurs in about 0.5 seconds. The uptake of
Oxygen is favoured the simultaneous loss of carbon dioxide which is then excreted in the expired air. Conversely the entry of carbon dioxide into the blood from the tissues facilitates Oxygen transfer to the cells.
At rest, mixed venous blood returning to the lungs contains 13-14ml of Oxygen per 100ml, but with severe exercise, the Oxygen content may fall to 34ml. In very active tissue, almost complete extraction occurs.
5.3 Preclinical safety data
Not applicable.
6. PHARMACEUTICAL PARTICULARS 6.1 List of excipients
None.
6.2 Incompatibilities
Liquid Medical Oxygen is non-flammable but strongly supports combustion (including some materials that will not burn in air). It is highly dangerous in the presence of oils, greases, tarry substances and many plastics due to the risk of spontaneous combustion with high pressure gases.
6.3 Shelf life
6 months
6.4 Special precautions for storage
Liquid Medical Oxygen cylinders should be stored:
• under cover and protected from the extremes of heat
• away from stocks of combustible material
• separately from industrial and other non-medical cylinders
• within the medical cylinder store, separately from other medicinal cylinders
• with full and empty cylinders stored separately
Liquid Medical Oxygen bulk storage tanks should be sited at least 3 metres from boilers and other sources of naked lights, fuel stores, paint stores and other volatile flammable materials.
6.5 Nature and contents of container
All storage vessels or liquid cylinders used for the storage of Liquid Medical Oxygen are manufactured from stainless steel or aluminium. They are constructed as a double skinned vacuum insulated vessel, with the interspace filled with an inorganic insulant to prevent any heat inleak.
Liquid cylinders are fitted with an internal vaporisation coil in the interspace, to convert the Liquid Oxygen to gas, for use by the patient. The bulk storage vessels have an external ambient heated vaporiser fitted to ensure that only gas is supplied down the pipeline to the ward outlet points.
The liquid cylinders have an operating pressure of up to 12.1 bar (g) and a capability of supplying vaporised gas at a rate of up to 300 litres/min for each cylinder.
The bulk storage vessels (VIE) have an operating pressure of up to 16 bar (g). The outlet flow capability depends upon the size of the vessel and the type of vaporiser system.
The valves are constructed from either high tensile brass or stainless steel. The regulator diaphragm and relief valve components, used to control the flow and pressure of the gas, are made from Oxygen compatible materials.
6.6 Instructions for use/handling
All personnel handling liquid cylinders should have adequate knowledge of the properties of the liquid and the gas, precautions to be taken, actions in the event of an emergency and the correct operating procedures for their installations.
A Preparation For Use
Prior to use:
• Ensure that the connecting face on the outlet valve is clean and the sealing washer fitted is in good condition.
• Open cylinder valve slowly
• Only use the appropriate regulator for the particular gas concerned
• Cylinder valves and any associated equipment must never be lubricated and must be kept free from oil and grease
B Leaks
Care should be taken to ensure there are no leaks between the regulator connection and the cylinder valve. The following precautions should be followed:
• Should leaks occur this will usually be evident by a hissing noise.
• Leaks can be found by brushing the suspected area with an approved leak test solution such as 1% Teepol HB7 solution.
• Sealing or joining compounds must never be used to cure a leak.
• Retighten the connection of the regulator to the valve with moderate force only, having depressurised the tailpipe or regulator. Always fit a new sealing washer if the leak can not be rectified by retightening the connection.
• Never use excessive force when connecting equipment to cylinders.
C Use Of Cylinders
When using liquid cylinders:
• Liquid cylinders should be handled with care and not knocked violently or allowed to fall.
• Liquid cylinders should only be moved with the appropriate size and type of trolley.
• Liquid cylinders should be firmly secured to a suitable cylinder support.
• Medical gases must only be used for medicinal purposes.
• Smoking and naked lights must not be allowed within the vicinity of liquid cylinders.
• After use cylinder valves should be closed using moderate force only and the pressure in the regulator released.
when the liquid cylinder is empty:
• The cylinder valve must be closed.
• Immediately return to the empty cylinder store for return to BOC.
D General
Hazards to health arise from intense cold or displacement of air by rapidly evaporating liquid and extreme care is needed when handling Liquid Medical Oxygen.
Transient exposure to very cold gas can provoke attacks of asthma in susceptible subjects and prolonged breathing of cold gas may damage lung tissue.
Due to the low temperature of Liquid Medical Oxygen (below -183°C at atmospheric pressures), the liquid, or even cold gases, can cause damage to the skin when directly in contact. Unprotected parts of the skin coming into direct contact with uninsulated items of cold equipment may also stick to the flesh and may be torn on removal.
It is recommended that non- absorb ant leather gloves and goggles should be worn when handling Liquid Medical Oxygen.
7. MARKETING AUTHORISATION HOLDER
BOC Ltd.
The Priestley Centre 10 Priestley Road The Surrey Research Park GUILDFORD Surrey, GU2 5XY.
8 MARKETING AUTHORISATION NUMBER(S)
PL 00735/0009R
9. DATE OF FIRST AUTHORISATION/RENEWAL OF AUTHORISATION
Date First Granted 01/09/1972
Date of Renewal 21/07/1992
10 DATE OF REVISION OF THE TEXT
25/05/2016