Unlike in the past, home oxygen users are on the go, and HMEs must weigh financial as well as lifestyle issues when providing oxygen to these patients

There are myriad factors to consider when determining the optimal ambulatory oxygen system for your patient and the home care organization. The clinical needs of the patient must be balanced against financial restraints placed on the durable medical equipment provider by the current home care reimbursement system.

A Little History
Current reimbursement for home oxygen provides the majority of funding for the stationary system and very small monetary support for the ambulatory needs of the patient. This economic reimbursement system is based on how home oxygen therapy was initially utilized throughout the United States and does not reflect today’s reality, which is that most of the cost today is in providing ambulatory systems. In the 1960s and 1970s, when oxygen therapy first became available for home use, the average patient was generally in the end stage of their disease process. The patient was typically not very ambulatory, and the average duration of usage was not longer than a few months. Oxygen was provided only in compressed gas cylinders—usually “H” cylinders. Ambulation was not a priority during this time period.

As technology advanced, the oxygen concentrator and liquid oxygen systems emerged in the 1980s and 1990s as the standard of care. The oxygen concentrator with a compressed gas “E” cylinder for ambulation was provided to a large majority of patients during this period. Liquid oxygen was supplied to patients who were considered highly ambulatory or were on a high liter flow. Reimbursement for liquid oxygen was based on the number of pounds of oxygen consumed by the patient. Patients began being prescribed oxygen earlier and remained on their systems for longer periods of time. Ambulation when providing home oxygen therapy became a consideration for the first time.

During the mid to late 1990s, there was a series of reductions in oxygen reimbursement. Medicare changes mandated that oxygen therapy services would be reimbursed modality neutral. This meant that the home oxygen provider would receive identical reimbursement levels regardless of whether liquid oxygen, an oxygen concentrator, or large compressed gas cylinders were used to meet the clinical needs of the patient. This caused the home care supplier to focus more on employing oxygen concentrators and compressed gas cylinders for their patients. Liquid oxygen became difficult to provide to large numbers of patients under the changes in Medicare policy. The difficulty was based not on the cost of the equipment but on the fact that liquid oxygen required regular deliveries to the patient’s residence.

New Technologies Offer Options
With the dawn of the 21st century, technology continues to improve and provide new options for the patient and oxygen provider. Oxygen conservation devices, while not a new innovation, have emerged for both compressed gas and liquid oxygen systems. Liquid oxygen systems have become more efficient with the development of low loss systems. These systems are designed to be more efficient and decrease oxygen evaporation from the stationary system, allowing the home care provider to fill the stationary vessel less frequently. The ability of the oxygen system to meet the ambulatory needs of the patient became one of the major factors in the selection of a home oxygen system. Smaller and lighter compressed gas and liquid systems used with a conservation device slowly have became the standard for ambulatory oxygen. Many of these systems weigh between 4 and 6 pounds and were designed to be carried on patients’ shoulders or around their waists. A series of home oxygen therapy consensus conferences have been held and attended by leading physicians, clinicians, and manufacturers with the goal of improving the delivery of home oxygen therapy. One outcome from the consensus conferences has been, for the first time, a definition of an ambulatory oxygen system. It was defined as an oxygen system that weighed less than 10 pounds and could provide a minimum of 4 hours of therapy. Based on this new definition, an E cylinder no longer met the criteria because it weighed more than the 10-pound weight limit.

Special Delivery
The 21st century also has seen a new category of oxygen systems based on new technological advances. This category was dubbed the deliveryless system. These systems are either an oxygen concentrator system that has the ability to fill a compressed gas cylinder or a portable oxygen concentrator that can be operated on direct current, alternating current, or a battery. These systems are called deliveryless because no routine deliveries of compressed gas cylinders or liquid oxygen are required. The downside to the use of deliveryless oxygen systems is that the cost of acquisition for these systems is approximately four to five times more than the cost of a traditional home system with an oxygen concentrator and compressed gas cylinders with a conservation device.

Decisions, Decisions
Today, with the wide range of choices, including portable oxygen concentrators, concentrators that fill their own cylinders, liquid oxygen systems, and the traditional concentrator with compressed gas cylinders, the home oxygen therapy provider has many options to meet the needs of the patient and the organization. There are several factors to evaluate when determining what is optimal. Based on these factors, what is considered optimal can vary from organization to organization.

Aspects to consider in regard to the patient include:
• Prescribed liter flow
• Prescribed usage—continuous, exertion, or nocturnal
• Ability to tolerate an oxygen conservation device
• Average length of time ambulating outside residence
• Size of residence
• Patient/caregiver aptitude

The liter flow of the patient is critical; many of the different systems available have liter flow limitations. How often the oxygen will be required will influence the system of choice as well. A patient who requires oxygen only with exertion and not at rest will receive significantly longer duration of oxygen from the same ambulatory system. There are many oxygen conservation devices available, but keep in mind that each conservation device provides its own equivalent to continuous-flow oxygen. There are currently no standards on the size of the oxygen bolus delivered to the patient with each inhalation. Oxygen conservation begins with titrating continuous flow to the lowest liter flow that provides appropriate oxygen saturation at rest, with activity, and nocturnally. The conservation device flow should be titrated based on the patient’s oxygen saturation and should be retitrated if the patient is changed from one manufacturer’s oxygen conservation device to another manufacturer’s.

Patients ambulate inside their residence as well as out in the community. The average size of a residence in the Unites States has increased in the past few decades, and in many residences 50 feet of oxygen tubing from the stationary system is not adequate. A plan must be developed using patients’ ambulatory systems to allow them to get to all rooms of their residences. Historically, a patient was discouraged from using their ambulatory system in their residence. Today, however, to get to a laundry room in the basement, get the mail from a street-side mailbox, sit on a porch, etc, the ambulatory system must be utilized even when the patients do not leave their residences.

The 50 feet of oxygen tubing can be a hazard as well for some patients. If a patient or another person living in the home uses a walker or is unsteady on their feet, working to eliminate the oxygen tubing running throughout the dwelling can decrease the risk of an injury due to falls. The ability of the patient and/or caregiver to properly and safely operate the system must be evaluated as well. Some systems are easier to operate or require less manual dexterity, which can be critical for some senior citizens with limited vision or arthritis in their hands.

Aspects to consider in regard to the home care organization include:
• Equipment acquisition cost
• Average cost of oxygen delivery
• Distance between patient and the organization
• Reimbursement

With the rapid change in technology, equipment acquisition can be a challenge. What was optimal 1 or 2 years ago may not be optimal today for every patient, but home care providers cannot continually update their entire inventories based on changes in technology. Assessing each patient at the time their plan of care is developed can allow an organization to utilize new technology where it is most beneficial and continue to use more traditional systems where there is less need for ambulation. Equipment costs can be spread out through leasing if the cash flow of the organization does not permit purchasing. Equipment is assigned a useful life for accounting purposes, but due to the rapid changes in technology, it can be difficult to determine the useful life of a piece of equipment purchased today. Equipment purchased today may be obsolete in 2 or 3 years if technology continues to advance at its current pace.

The organization must also determine the cost to make a delivery to a patient’s home. Included in this determination should be the cost of a customer service representative taking the order or reorder, data entry, warehouse personnel preparing the order, delivery of the order, confirmation of the order, cylinder filling, and lot number tracking.

Service areas vary widely between organizations: For examples, some urban providers have all their patients within 30 to 45 minutes’ drive time from their warehouses, while a rural provider may travel several hours to service a patient. Some providers are using deliveryless systems for their outlying patients and providing a more traditional delivery model for patients living closer to the organization. Still others are using a deliveryless model for all their patients, regardless of their proximity to the provider. Some organizations have not begun to use the deliveryless model at all, due to factors such as large inventories of liquid oxygen systems, traditional oxygen concentrators, and compressed gas cylinders.

Reimbursement continues to decline, and, to date, the 36-month Medicare cap on oxygen reimbursement is in effect; it is unclear if it will be repealed by Congress. This means, as it stands today, that any Medicare patient who is on oxygen therapy for greater than 36 months would own their equipment in the 37th month. Declining reimbursement has meant to most providers the need to improve the efficiency of how oxygen services are provided. Delivery is the largest cost in providing services to an oxygen patient. Many organizations have looked at deliveryless systems as a way to cut or eliminate routine delivery costs. Other organizations using compressed gas or liquid oxygen are providing larger quantities of oxygen per delivery to the patient to decrease the number of routine deliveries. How to factor the Medicare cap into an organization’s plan is still being worked out, as there are still many unanswered questions on how service and ambulatory systems will be handled under this cap. Keep in mind, however, that the average Medicare patient uses home oxygen between 24 and 30 months. Based on these statistics, less than half of the home oxygen patients will reach the cap.

There is no right or wrong answer to whether liquid oxygen, portable concentrators, concentrators that fill compressed gas cylinders, or compressed gas cylinders in conjunction with a standard concentrator are best if the patient’s clinical and ambulatory needs are met. A delicate balance must be maintained between the needs of the provider and the needs of the patient. The provider must have the ability to analyze both the clinical benefits and financial implications of the available home oxygen systems available for use today to meet patient and organizational needs.

James P. Stegmaier, RRT-NPS, RPFT, CCM, is president of Cardinal Home Medical in Lakewood, Ohio.

Further Reading
Bliss PL, McCoy RW, Adams AB. Characteristics of demand oxygen delivery systems: maximum output and settings recommendations. Respir Care. 2004;49:160-5.

Hoisington ER, Miller DA, Adams CA, McCarthy K, Stoller JK. Impact of a program to provide patients with comparative information about providers of durable medical equipment for home respiratory care. Respir Care. 2004;49:1305-6.

King JE. How do I choose a supplemental oxygen delivery device? Nursing. 2003; 33:32.

Problems in prescribing and supplying oxygen for Medicare patients. Am Rev Respir Dis. 1986;134:340-1.

US General Accounting Office Report to Congressional Committees: April 1999. Medicare access to home oxygen therapy largely unchanged; closer HCFA monitoring needed. Washington, DC: US General Accounting Office; 1999. Publication GAO/HEHS-99/56.