Idiopathic Pulmonary Fibrosis or IPF is a rare disease characterized by progressive replacement of normal lung tissue with scar tissue. The scarred tissue becomes thick and stiff making it harder for the lungs to exchange oxygen. Supplemental oxygen therapy helps alleviate some of the stress on the heart and other organs caused by pulmonary fibrosis. Oxygen is considered a medication and must be prescribed by a physician. Insurance companies have strict requirements for paying for oxygen and so your physician will have to document your oxygen saturations at rest and with exercise. Below are several different types of oxygen delivery systems that your physician may recommend.
Oxygen Flow Options
Low flow oxygen cannula
This is the most common type of oxygen cannula. They are inexpensive and comfortable. There are different brands that have different characteristics such as the length of the nasal prongs and the softness of the plastic. Low flow cannulas are designed to deliver flow rates of between 0.5 and 3 liters per minute (LPM)
High flow oxygen cannula
This type of cannula is designed to deliver higher oxygen flow rates, typically 4-10 LPM. They differ from low flow cannulas in that they have a larger lumen or internal dimension. This wider configuration allows oxygen to flow more easily with less resistance.
Demand oxygen or flow conserving devices
During continuous flow, much of the oxygen that flows through the nasal cannula is wasted. Patients only actually use oxygen during inspiration. The demand or pulse flow systems allows oxygen to flow only when a valve senses inspiration. This increases the efficiency of the tank by 3-7 fold. For example, a tank that would last 3 hours during continuous flow would last 9 hours or more with a pulse system. The main disadvantage is that patients requiring higher flow rates do not receive enough oxygen flow. For example, patients that typically use 3 LPM continuous flow may need to increase their flow rate to 5 LPM by pulse flow.
Some regulators have the ability to switch between continuous and demand flow. This is optimal for patients that use less oxygen at rest and require higher flows during activity. It allows patients to easily switch back and forth.
This type of nasal cannula is designed to improve the amount of oxygen that is inspired. It can also be used to reduce the oxygen flow rate, which may increase the duration that a portable tank can be used. For example, a reservoir cannula set at 2 LPM delivers the equivalent of 4 LPM with a low flow cannula. The only disadvantage of a reservoir cannula is that it is a bit bulkier than low flow cannula and more expensive.
Types of Oxygen Delivery Systems
There are two types of oxygen concentrators. The most common units are large and require continuous electricity. They are designed to be used at home. They tend to be quite noisy and patients often prefer to place them in an unused room. Oxygen tubing is then used to allow patients to walk around the house. Care must be taken not to trip over the long tubing that runs throughout the house. Typical concentrators can deliver 5-6 LPM of oxygen. Higher quality units can deliver up to 10 LPM.
When using an oxygen concentrator, your electricity bill will increase. In some cases, you may be able to get a reduction in your bill by filling out some forms. Also, everyone who uses an oxygen concentrator at home should have a plan for power outages. First, register with the local energy company so that your power is restored as a priority. Second, you must have backup portable tanks that are available for power outages. The electric company will request your physician sign a form confirming that oxygen has been prescribed for you and is medically necessary.
Portable oxygen concentrators (POC)
These systems have become much more popular in the past five years. They have rechargeable batteries and are lighter in weight than the older type of concentrators. The FAA and TSA now require this type of oxygen delivery system for use during airplane travel.
Key issues with portable concentrators are a trade-off between size, weight and the amount of oxygen the device can deliver. Most units deliver up to 3 LPM with a demand or pulse system. Larger units can deliver 5 LPM pulse flow. Patients should confer with their pulmonary specialists when planning to purchase a portable concentrator. Given their cost, it is important to choose a unit that can deliver an appropriate amount of oxygen now and for the next year or two as your oxygen requirement changes.
Most oxygen companies will provide a POC for patients that are planning air travel. It is important to plan in advance as it can take a few weeks to coordinate.
This is the usual way that portable oxygen is delivered. Tanks of different sizes are available. The size of the tank is determined by the flow rate that patients require. Patients that require higher flow require larger tanks. Oxygen companies deliver tanks periodically. Patients are provided with one or two “regulators” which allows the tank to be accessed and used for oxygen delivery.
Auto fill compressed oxygen
This system uses the patient’s large home concentrator to refill portable oxygen tanks.
The type of oxygen system uses a very large reservoir tank of compressed liquid oxygen in the home. Patients connect their nasal cannula to the tank. When away from home, patients have small tanks that they fill from the larger tank. Liquid oxygen has many advantages for patients. First, no electricity is required. Second, the portable tanks are light weight and can deliver high flow rates easily. The main disadvantage is cost. As a result of higher cost for oxygen companies, most companies are phasing out liquid oxygen.
In this system, your physician performs a small surgery to insert a thin oxygen cannula directly through your neck. The main advantage of this system is that lower flow rates efficiently deliver oxygen. Furthermore, patients that are very troubled by the cosmetic aspect of oxygen cannula on the face may find a transtracheal oxygen catheter more acceptable. There are several problems with the system. First, insertion requires a small surgery. Patients that would benefit most from this system are at high risk for complications from surgery. Second, thick mucous can form on the catheter and result in difficulty breathing. Lastly, some patients have cough from the catheter.