Summary of medicine characteristics - 20% CARBON DIOXIDE / OXYGEN MEDICAL GAS MIXTURE
1 NAME OF THE MEDICINAL PRODUCT
20% carbon dioxide / oxygen medical gas mixture
2 QUALITATIVE AND QUANTITATIVE COMPOSITION
2 QUALITATIVE AND QUANTITATIVE COMPOSITION20% Carbon Dioxide / Oxygen Medical Gas Mixture is supplied in high pressure gas cylinders. The Oxygen and Carbon Dioxide complies with the European Pharmacopoeia Specification (1998) and with their respective Marketing Authorisations.
The mixture specification is as follows:
Carbon Dioxide: 20% ± 1%
Oxygen: Balance
The Medical Oxygen specification is as follows:
Medical Oxygen Purity 99.5%
Maximum Impurity Levels
Carbon Monoxide 5 vpm
Carbon Dioxide 300 vpm
Moisture 50 vpm
The Medical Carbon Dioxide specification is as follows:
Medical Carbon Dioxide Purity 99.5%
Maximum Impurity Levels
Carbon Monoxide
Total Sulphur
Nitric Oxide / Nitrogen Dioxide
Moisture 50 vpm
20% Carbon Dioxide / Oxygen Medical Gas Mixture Cylinder and Valve Details.
20% Carbon Dioxide / Oxygen Medical Gas Mixture is supplied in high pressure cylinders filled to 137 bar (g). Conventional high pressure cylinder valves with side outlets, that conform to BS 341 (5/8” BSP F), are fitted to all 20% Carbon Dioxide / Oxygen Medical Gas Mixture cylinders. These cylinders are designed to be used with a pressure regulator.
A summary of 20% Carbon Dioxide / Oxygen Medical Gas Mixture cylinders, their size and construction and type of valve fitted are detailed below:
| Cylinder Size | Gas Content (litres) | Cylinder Construction | Valve Construction | Valve Outlet | Cylinder Pressure bar (g) |
| AV | 1370 | Aluminium | Brass | BS 341 No.3 Side Outlet Handwheel Valve | 137 |
| L | 6850 | Steel | Brass | BS 341 No.3 Side Outlet Handwheel Valve | 137 |
3. PHARMACEUTICAL FORM
Compressed Medical Gas.
4. CLINICAL PARTICULARS
4.1. Therapeutic indications
The need for pre-determined gas mixtures of carbon dioxide and oxygen has been sharply reduced in recent years. The most common use of 20% Carbon Dioxide/Oxygen Medical Gas Mixture is for physiological investigations.
4.2. Posology and method of administration
20% Carbon Dioxide / Oxygen Medical Gas Mixture is administered by inhalation through the lungs usually for a fixed period.
4.3. Contraindications
There are no contraindications for the use of 20% Carbon Dioxide / Oxygen Medical Gas Mixture in any age group.
The duration and circumstances of the exposure to 20% Carbon Dioxide / Oxygen Medical Gas Mixture is always at the discretion of the attendant physician who makes the decision in the light of the particular circumstances.
4.4 Special warnings and precautions for use
Administration of 20% Carbon Dioxide /Oxygen Medical Gas Mixture to patients with chronic respiratory disease or drug induced respiratory depression is potentially dangerous. It should not be given to acidotic patients.
Where the patient has been exposed to agents which are toxic to the lungs, such as Paraquat, the use gases containing more than 21% oxygen should be avoided.
20% Carbon Dioxide /Oxygen Medical Gas Mixture is non flammable but strongly supports combustion and should not be used near sources of ignition.
Smoking should be prohibited when using 20% Carbon Dioxide /Oxygen Medical Gas Mixture.
Under no circumstances should oils or grease be used to lubricate any part of the 20% Carbon Dioxide /Oxygen Medical Gas Mixture 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 20% Carbon Dioxide /Oxygen Medical Gas Mixture cylinders or equipment.
4.5 Interaction with other medicinal products and other forms of interaction
20% Carbon Dioxide / Oxygen Medical Gas Mixture will interact with anaesthetic agents when the concentration is raised and gives rise to cardiac dysrhythmias. The threshold for dysrhythmias varies with different drugs.
By altering pH, the use of 20% Carbon Dioxide /Oxygen Medical Gas Mixture influences the uptake and distribution by many drugs, including neuromuscular blocking agents and hypotensive agents.
20% Carbon Dioxide / Oxygen Medical Gas Mixture will interact with adrenergic substances such as adrenaline. They should not be used together.
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 Medical Oxygen/Carbon dioxide mixtures should be administered with caution and at levels kept as low as possible.
4.6. Pregnancy and lactation
20% Carbon Dioxide / Oxygen Medical Gas Mixture is not contraindicated in pregnancy and is unlikely to influence lactation.
4.7. Effects on ability to drive and use machinery
The inhalation of 20% Carbon Dioxide / Oxygen Medical Gas Mixture should be directly supervised by a clinician so that the question of driving or controlling machinery should not arise.
4.8 Undesirable effects
The use of 20% Carbon Dioxide / Oxygen Medical Gas Mixture may produce sweating, nausea and headache in a small number of patients.
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
The use of 20% Carbon Dioxide / Oxygen Medical Gas Mixture needs careful supervision.
5. PHARMACOLOGICAL PROPERTIES
5.1. Pharmacodynamic properties
20% Carbon Dioxide / Oxygen Medical Gas Mixture consists of 20% Carbon Dioxide with the balance being Oxygen. The pharmacological particulars of the constituent gases are as follows:
The characteristics of Carbon Dioxide are:
Odourless, colourless gas
Molecular weight 44
Sublimation point 78.5°C (at 1 bar (g))
Density 1.872 kg/m3 (at 15°)
The effect of inhaling Carbon Dioxide, or of its accumulation in the body through ventilation defects, varies with the tension achieved in the blood, the duration and condition of the exposure and the susceptibility of the individual concerned.
The characteristics of Oxygen are:
Odourless, colourless gas
Molecular weight 32
Boiling point 183.1°C (at 1 bar (g))
Density 1.355 kg/m3 (at 15°C)
Oxygen is present in the atmosphere at 21% and is an absolute necessity for life.
If a normal conscious patient inhales 20% Carbon Dioxide / Oxygen medical Gas Mixture, the rate and depth of breathing rise and the minute volume increases. The skin becomes warm and pink and there may be sweating and a sense of discomfort. However, when the subject returns to breathing in air, an “off-effect” is commonly seen with malaise, pallor, headache and occasional nausea and vomiting, probably due to metabolic effect induced by inhaling a volatile acid.
5.2. Pharmacokinetic properties
When 20% Carbon Dioxide / Oxygen Medical Gas Mixture is inhaled, absorption from the lungs into the blood is rapid and a new equilibrium between the concentration in alveolar air and that in the blood is soon established. The gas is carried partly in solution in the plasma, but mostly either as bicarbonate or as carbamino compound. The relative quantities in solution and as bicarbonate regulate the reaction of the blood and buffer any change in pH produced by stronger organic acids. The blood concentration of Carbon Dioxide is set at a higher level and the excretion of the gas is adjusted to maintain the new equilibrium by increasing output.
5.3. Preclinical safety data
None stated
6. PHARMACEUTICAL PROPERTIES
6.1. List of excipients
None.
6.2. Incompatibilities
The constituent gases of 20% Carbon Dioxide / Oxygen Medical Gas Mixture are chemically inactive and will not normally react with other compounds at normal temperatures.
However, the Medical Oxygen component of 20% Carbon Dioxide / Oxygen Medical Gas Mixture strongly supports combustion and will cause substances to burn, including some materials that will not normally 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 in the presence of Medical oxygen in relatively high concentrations.
6.3. Shelf life
36 months.
6.4. Special precautions for storage
2 0% Carbon Dioxide / Oxygen Medical Gas Mixture cylinders should be stored as follows:
Cylinders should be stored under cover, preferably inside, kept dry and clean and not subjected to extremes of heat or cold, away from stocks of material.
Cylinders should not be stored near stocks of combustible materials or near sources of heat.
Medical cylinders should be stored separately from industrial and other non-medical cylinders.
Full and empty cylinders should be stored separately.
Full cylinders should be used in strict rotation.
Segregate medical cylinders containing different gases within the store.
Warning notices prohibiting smoking and naked lights must be posted clearly.
Emergency services should be advised of the location of the cylinder store.
6.5 Nature and contents of container
All cylinders used for the storage of 20% Carbon Dioxide / Oxygen Medical Gas Mixture are manufactured from high tensile steel or Aluminium with a designed working pressure of at least 137 bar (g).
The cylinder valves are constructed from high tensile brass with a steel spindle fitted with a Nylon 66 insert.
6.6 Instructions for use and handling, (and disposal)
All personnel handling 20% Carbon Dioxide / Oxygen Medical Gas Mixture cylinders should have adequate knowledge of the properties of the gas, precautions to be taken, actions in the event of an emergency and the correct operating procedures for their installations.
For 20% Carbon Dioxide / Oxygen Medical Gas Mixture cylinders, prior to use, ensure that:
An appropriate medical regulator is used with the cylinder suitable for the 20% Carbon Dioxide / Oxygen Medical Gas Mixtures.
The connecting face of the regulator is clean and the sealing washer fitted is in good condition.
The cylinder valve is opened slowly
The cylinder valves and any associated equipment is not lubricated and kept free from oil and grease.
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 jointing compounds must never be used to cure a leak.
Should a leak occur between the valve outlet and the detachable regulator, depressurise and remove the regulator and fit a new ‘O’ ring. Reconnect the regulator to the valve with moderate force only. If the leak persists, fit a replacement regulator.
Never use excessive force when connecting equipment to cylinders.
When cylinders are in use ensure that they are:
Handled with care and not knocked violently or allowed to fall.
Only be moved with the appropriate size and type of trolley or handling device.
Firmly secured to suitable cylinder support.
Only be used for medicinal purposes.
Not used in the vicinity of persons smoking or near naked lights.
After use the cylinder valves should be closed using moderate force only and the pressure in the regulator released.
When the cylinder is empty ensure that:
The cylinder valve is closed.
The valve outlet cap. Where fitted, is replaced.
The empty cylinder is immediately returned to the cylinder store for return to BOC.
7. MARKETING AUTHORISATION HOLDER
BOC Ltd.
The Priestley Centre
10 Priestley Road
The Surrey Research Park
Guildford
Surrey, GU2 5XY.
8. MARKETING AUTHORISATION NUMBER
PL: 00735/0013R.
9. DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATION
9. DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATIONDate First Granted: 01/09/1972
Date of Renewal 27/03/1991.