Home Oxygen

Liquid Oxygen

Liquid Oxygen system store oxygen at 273Fahrenheit in a tank that is called a dewar. As the oxygen passes through warming coils it becomes gaseous. The flow can vary from ¼ to 15L/min. The standard liquid oxygen tank lasts for a week at 2L/min and is refilled as needed. The main advantage of the liquid system is that small lightweight tank can be filled from the stationary system that allows the system to be ambulatory. The small tanks last for 8 hours with a flow rate of 2L/min and they are fairly heavy; the smaller units last correspondingly less time.

The other advantages of the liquid system included quitnes and no need for electricity. The system is more costly than other oxygen system the convenience makes it the best choice for the child who wants to be able to travel away from home. If the flow rate is than 4L/min, refill need to be made frequently. There is continued evaporative loss so that there is some wastage. Reimbursement for liquid system  may be less than optimal for DME company.

Oxygen Concentrator

This is an electrical device that removes nitrogen from room air and delivers oxygen to the patient at rates of ¼ to 6L/min. The concentrator is quite large and noisy and does require electricity to function. The advantage over the liquid system is that there is no need to refill. Running the unit increases the monthly utility bill by approximately $27. It is most useful for patient who use oxygen only at night or for those who remain in bed.

Compressed Oxygen Systems

The compressed oxygen tanks used is in the hospital may be used int the home. The largest is the H tank which last for two days at 2L/min. The H tank is useful as a back-up for the concentrator. It is not good as a primary source because of the need of replace tank every few days. Smaller tank are E and D tanks. The D tanks are small enough to carry in a shoulder bag. The E and D tanks are useful for people who only spend a limited time away from home. Cylinders and tanks containing compressed gas are the most economical method of delivering oxygen. The container must be supported either by a chain or in a base of cart. The tanks must be placed or stored away from any heat source.

Some devices are equipped to conserve oxygen to extend usage. These include the reservoir cannula, the pulsed-dose system, and the transtracheal oxygen system. The reservoir canulla stores the continuously following oxygen during expiration so that a bolus is available for the next inspiration. Pulsed-dose systems deliver an increased amount of oxygen during the beginningof inspiration and can reduce the amount of oxygen utilized overall. Transtracheal oxygen systems have not been used much in pediatrics. They involve insertion of  a catheter into the trachea percutaneously (from the neck), which delivers oxygen directly into the trachea.

Oxigen is delivered to the airway by facemask or by cannula. The nasal cannula can be connected to the source by tubing that can be as long as 50 feet to allow some mobility. Oxygen masks are less used in the home than in the hospital. They can deliver higher concentrations of oxygen than cannulae. The simple mask requires a high flow rate (5-10L/min) and the non-rebreather and Venturi need even higher flow rates. The pescription for oxygen usually will define the flow rate and the duration (number of hours). On occasions, oxygen will be required only during sleep and activity. It is useful to evaluate whether the oxygen can be discontinued for brief periods (e.g., during a shower or when eating). Continuous pulse oximetry is usually not recommended in the home because of the frequency of false alarms. It is helpful if there is intermittent checking of oxygen saturation to maintain an appropriate level.