Respiratory gases are big business; whether fed through a pipeline system into a hospital, or delivered by cylinder to people in their homes, they are imperative to the smooth running of medical procedures, and are relied upon heavily by millions of people worldwide
who depend on breathing aids for a better
quality of life.

Classified as those gases which are suitable for inhalation, different combinations of respiratory gases are used in a range of situations, whether it be to relieve pain, anaesthetise in order to operate, or simply make breathing easier for an individual with respiratory problems.

Studies have also demonstrated the potential of inspired gases to treat a range of other conditions; the hyperbaric oxygen chamber, originally used to treat divers suffering from the bends, is now thought to be beneficial to those who have suffered a stroke, or who are autistic.

Enter the industrial gas companies; they ensure a regular supply is distributed to hospitals and other medical institutions, and have gradually moved into the homecare sector, delivering direct to members of the public as well.

Many of these gases are now classified as pharmaceuticals, which means that the gas companies are required by regulatory authorities to obtain licenses for each gas, and upgrade their production and delivery processes.

As with all aspects of medicine, research is ongoing, and technological advances have meant that the way respiratory gases are now delivered, used and administered, differs from that which was the case as little as ten years ago.

As hospitals become more sophisticated and clinicians gain a better understanding of the role of these products in patient care, more gas per head is used.

The gas companies themselves have become increasingly involved in the research element, not just for the gases themselves, but for the technology needed to administer them; most play a far more active role than simply delivering the gases – new developments and discoveries have led to increased sales and a rapidly expanding business.

The gases
The difference between medical gases, and gases for industrial sales, is that the gas purity in medical gases has to be much more strictly controlled, and additional safety procedures must be employed.

Unlike oxygen used in a steel works for example, medical oxygen must undergo stringent tests to ensure it is suitable for inhalation. Quality is ensured by documented processes, separate production lines, and detailed, documented batch records.

In terms of respiratory gases; medical oxygen, nitrous oxide, carbon dioxide, helium and air are the primary gases used.

Mixtures of these are common in order to achieve a specific effect, and with each of them, oxygen must be administered in the mix in most cases to ensure the patient’s safety.

Oxygen supports life, and is therefore fundamental to medicine. It was first used in the medical field in the early 19th century, although it took another 150 years for it to be used properly with patients, and it is only since the mid 20th century that oxygen therapy has been considered a legitimate scientific method.

Everything from the intra-uterine growth of the foetus, to the very end of life, requires an adequate oxygenation of the transport media, the blood, and from that all cells within the body rely on receiving an adequate supply of oxygen.

Medicine could not have progressed as dramatically as it has without the use of this vital gas; it provides a basis for most modern anaesthetic techniques, and when administered through a face mask, treats shock, carbon monoxide poisoning, cardiac and respiratory arrest, aids in resuscitation, and provides life support for artificially ventilated patients.

Medical nitrous oxide, or laughing gas as it is more commonly referred to, has been widely used as a background anaesthetic since the late 19th century.

It has weaker anaesthetic properties than other gases, and is therefore supplemented with a potent volatile agent when inhaled, in order to achieve the desired anaesthetic effect.

Its low blood/gas solubility means it allows for faster induction times when used with another agent, and by including it in the mix, up to half as much dosage of the other agent is needed.

Medical carbon dioxide is used minimally with oxygen or air as a respiratory stimulant to promote deep breathing, or to rapidly increase the depth of anaesthesia when volatile agents are being administered.

The most common of the mixtures are Entonox® (also called Livopan®) and Heliox.

Entonox® is a 50/50 mixture of oxygen and nitrous oxide. Demanded by mothers-to-be as labour takes its toll, or administered to a patient with a broken limb who is about to be moved, the gas is inhaled via a mouthpiece attached to a demand valve system, and swiftly dampens the pain.

As the patient breathes, the demand valve – connected to either a standard wall outlet, or to a regulator on a cylinder – opens, delivering the gas as the patient inhales, and closing again during exhalation to conserve the product.

Heliox is an 80/20 mix of helium/oxygen, which is three times less dense than air – a property which makes it easy to inhale and exhale. For this reason, it is a favourable choice for medical professionals treating patients with conditions like croup or cystic fibrosis.

Heliox has been shown to reduce the effort of breathing for a patient, as it aids the clearance of carbon dioxide.

Delivery and storage of these gases varies depending on the customer’s needs. A large hospital might have several on-site containers, each holding a different gas, with a pipeline system feeding it through to the wards. These containers are regularly refilled by the gas company to ensure a constant supply.

An outpatients unit located on a different site to the main hospital still requires gas, but on a smaller scale, and so is likely to have a regular supply of liquid cylinders delivered – storing gas in its liquid form takes up far less room than storing it in its gaseous state, therefore more gas can be stored.

For a doctor on call who may only need to administer oxygen to a patient once or twice a month, a small, portable gas cylinder would be the best choice.

Advancing technologies
Respiratory gases are fundamental to modern medicine, therefore research must be continuous.

The major gas companies play an active role in this research, developing new innovations to improve on methods already in place, and to develop new ones.

In December 2007, Air Liquide’s LENOXe™ anaesthetic was used for the first time in France.

LENOXe™ is the first xenon-based anaesthetic to be marketed in Europe. It is composed of xenon, a noble air gas, and is administered in a mixture containing oxygen.

The anaesthetic properties of xenon have long been known – the first recording was in 1938 following deep-water dives – however, it has taken much research and development by Air Liquide to be able to broaden the use of the gas.

The company has obtained marketing authorisation for 12 European countries, and developed the Felix Dual, an anaesthesia device suitable for xenon, as well as conventional anaesthesia using other gases.

Xenon offers an environmentally friendly alternative to other gases, causing no pollution when returned to the atmosphere. It is effective and reliable as an anaesthetic, making it a favourable alternative to conventional gases. Routine use of the gas is considered unlikely however, due to the significant costs involved.

In a 2008 press release about the first use of xenon in France, Jean-Marc de Royere, Senior Vice-President of Air Liquide in charge of Healthcare said, “As our research people explore the medical potential of xenon and other medical gases, particularly for anaesthesia, intensive care and pain relief, new fields are opening for Air Liquide in healthcare.”

The introduction of xenon as an anaesthetic is a significant milestone in anaesthesia, and exemplifies how the industrial gas companies are looking further into the properties and uses of gases in order to expand their businesses.

Healthcare divisions of gas companies are also serving patients directly in their homes, as well as setting up their own care services – such as Linde Healthcare’s REMEO® centres.

Focused on patients requiring long term ventilation, REMEO® bridges the gap from the hospital to the home, with dedicated ventilation and weaning centres.

Patients stable enough to return to their families can be further supported with REMEO®, as Linde provides specialised staff and state of the art medical equipment at home.

Previously, the patient was the customer of the homecare provider, and the homecare provider was the customer of the gas company. Now, the patient is the customer of the gas company, and deals with it direct.

The cost of giving a patient a bed in hospital is high; it is far more cost effective for the patient to be cared for in their own home.

In Tier 1 company Air Liquide’s full year 2008 financial results, the company claimed Homecare had risen significantly by 12.3% across Europe, compared to the previous year.
The industrial gases industry has seen and continues to see double digit growth in the homecare sector in Europe.

Things appear to be different in the US however, as healthcare operations have been seen to be less profitable. Air Products recently sold a significant proportion of its homecare business, claiming it no longer provided a strategic fit with its portfolio.

Dealing with the end user in the medical field is most unusual for a gas company. Cutting out the distributor means respiratory gases have become big business for the gas companies; medical gases have always been a significant growth driver for the industrial gas industry, but this added market goes a long way in sustaining that stability in most cases, especially in the current economic climate.