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Hyperbaric Oxygen Therapy in Wound Care: A Service Under True Pressure

“If confusion is the first step towards knowledge, I must be a genius.” Larry Leissner

  Despite the large body of basic science data supporting its mechanism of action as well as prospective trial data, hyperbaric oxygen therapy (HBOT) has been accused of being “a therapy in search of a disease” in two peer-reviewed publications.1,2 These papers have been cited countless times as evidence that HBOT cannot find a defined role in the treatment of patients. The US Food and Drug Administration (FDA) in 1976 “grandfathered” in the 13 indications for HBOT that were supported by the Undersea and Hyperbaric Medical Society (UHMS) at the time. As a gas delivered via a medical device (hyperbaric chambers are Class II medical devices as cleared by the Center for Devices and Radiologic Health), the FDA currently views HBOT as a combination product (drug-device), specifically medical-grade oxygen (a drug) delivered in a hyperbaric chamber (a device). UHMS regularly produces documents to summarize the literature supporting the clinical use of HBOT. Updated information is produced approximately every 2-3 years as the UHMS’ HBOT committee report and is available from UHMS at Since 1997, UHMS has refined the problem wound indication to more specifically address diabetic foot ulcers (DFUs) and has added two new indications: central retinal artery occlusion (CRAO) and idiopathic sudden sensorineural hearing loss (ISSNHL). Although included in the list of UHMS-approved indications, CRAO and ISSHNL are currently not FDA approved, and when treated in a hyperbaric environment would be seen as an “off-label use” of HBOT.

Physician Supervision of Hyperbaric Oxygen Treatment
Business Briefs: Let NCDs and LCDs Guide the Way to HBO Reimbursement

  The Centers for Medicare and Medicaid Service (CMS) provides a national coverage determination (NCD) for HBOT. In 1997, CMS (then the Healthcare Financing Administration) clarified its coverage policy, which had always excluded thermal burns, and in 1999 clarified the physician-supervision requirement. Subsequent policies concluded that “preparation and preservation of compromised skin grafts” was not intended for the primary management of wounds, so this indication was removed. However, in 2003, CMS expanded coverage for diabetic ulcers of the lower extremity. As of 2014, CMS does not cover the treatment of thermal burns, CRAO, or ISSNHL.

  The quagmire of accepted indications, covered indications, and off-label indications raises the question, “Who decides what is an accepted indication for HBOT?” Many entities are weighing in on this topic with conflicting indications and requirements. This disparity between carriers (read “payers”) constitutes a major threat to the viability of HBOT on a number of fronts. Not only are the accepted indications radically different between various payers, but the requirements for the credentialing and education of the providers of HBOT are also becoming more specific, restrictive, and, in many instances, so contradictory as to make compliance impossible.

Reduced Coverage of HBOT

  Individual Medicare Administrative Contractors (MACs) have the opportunity to refine Medicare’s hyperbaric oxygen NCD by issuing local coverage determinations (LCDs) or articles that can provide medical coverage guidelines. If the MAC chooses to use the LCD option, the LCD is released for public comment and interested parties may contribute opinions that may impact the final version of the LCD.

  Should the MAC choose to release an article instead, there is no recourse since the article has no public-comment period. A number of MACs have proposed new LCDs or articles on HBOT. Perhaps the most widely discussed has been the recent draft LCD issued by Novitas Solutions Inc. Novitas covers two jurisdictions: “JL,” which spans Pennsylvania, New Jersey, Maryland, Delaware and Washington, DC; and “JH,” which spans Colorado, Oklahoma, New Mexico, Texas, Arkansas, Louisiana, Mississippi, Indian Health Services and Veterans Affairs.

  The Novitas draft LCD for HBOT, which is currently on hold, had a number of areas of concern that were addressed by UHMS and others during the comment period. One might think that a problematic LCD in another region doesn’t affect facilities outside of that jurisdiction, but that’s not the case. Since the national coverage policy on HBOT has not been reviewed in more than 10 years, the potential that the draft Novitas LCD might become the new NCD is chilling.

  Recently, BlueCross BlueShield of Tennessee Inc. adopted the 17th edition of the MCGTM Guidelines (formerly the Milliman Care Guidelines®) for HBOT, which has removed all HBOT indications except for DFUs, gas embolism, carbon monoxide (CO) poisoning, decompression illness and severe anemia. Since MCG is proprietary, there is little opportunity to comment about the appropriateness of the clinical decision-making.

  Similar positions have been taken by Hayes Inc., a commercial healthcare review business that provides best-practices guidance to customers, one of which is the state of Washington. Blue Shield of California made major changes to its policy (effective Sept. 27, 2013) and now considers the following diagnoses investigational and are not approved for HBOT: acute peripheral arterial insufficiency (APAI), necrotizing soft-tissue infections, compromised skin grafts/flaps, radiation-induced injury to the head and neck (although it does approve osteoradionecrosis and the Marx protocol), acute central retinal artery insufficiency, acute thermal burns, ISSNHL, and intracranial abscess. The decision by these private payers to place commonly used HBOT indications on the “experimental list” is ominous.

  Medicare’s managed care plans currently have flexibility in how closely they adhere to CMS guidelines. If they choose to use the parent company guidelines that are based on proprietary evidence assessments for which there is no public comment mechanism, radical changes occur covertly. The proprietary nature of the guidelines makes acquiring copies very difficult, since the guidelines are not made available to the taxpaying public. While Medicare Advantage plans may adhere to the national standards, local Medicaid policy is more likely guided by the HBOT policies that exist under the administrator of the plan, without any opportunity for public comment.

  The draft Novitas LCD had too many problems to discuss in detail here. Furthermore, since the policy was rescinded, it is not clear which direction a future policy will take. Nevertheless, a number of issues merit attention. Although Novitas did not limit the indications that were covered for HBOT, it did change the place of service in which certain conditions could be treated. A number of conditions would only be covered if the treatment for these conditions begins when the patient is an inpatient.

  The implications of this draft LCD are huge. Not only would the MAC dictate the practice of medicine, but the MAC proposed coverage determinations that cannot be uniformly applied in a clinical setting.

  For example, many patients who are treated for CO poisoning remain outpatients and others are transferred from one facility to another for care and never get “admitted” at the facility in which they receive HBOT. That is certainly true for APAI (ICD-9-CM diagnosis codes 444.21, 444.22, and 444.81). This indication is covered if revascularization is documented and perfusion is improved. However, many endovascular revascularization procedures are performed on an outpatient basis, and thus subsequent HBOT would not be covered under these limitations.

Do Emergency or HBOT Services Matter?

  There has been a dramatic reduction in the availability of emergency HBOT services over the past two decades. Recently, charges for outpatient HBOT treatments were denied by Novitas due to lack of documentation that an Advanced Cardiac Life Support (ACLS) team was available onsite while HBOT therapy was being administered. The policy states, “No payment will be allowed for HBOT without documentation that a trained emergency response team is available and that the setting provides the required availability of ICU services that could be needed to ensure the patient’s safety if a complication occurred.” Charges for routine outpatient HBOT were denied despite their being a physician onsite supervising HBOT and despite the fact that the program was physically located in an acute care setting.

  The rescinded draft Novitas LCD discussed already had language requiring ACLS certification by all HBOT staff and required that for payment of certain HBOT indications, the course of treatment had to begin while the patient was an inpatient. It is not likely that any MAC will develop policies mandating that hyperbaric facilities provide treatments to hospital inpatients or provide emergency hyperbaric services. However, it is safe to assume that MACs are taking a closer look at the environment in which HBOT is provided and asking whether the HBOT facility really meets the criteria required to be reimbursed as a hospital-based outpatient department (HOPD).

  What’s concerning is that the nearly universal decision by hyperbaric facilities to observe the same hours of operation as a doctor’s office - to treat patients with roughly the same level of acuity as a doctor’s office - not to treat currently hospitalized patients and not to handle emergencies - sends a message to CMS that HBOT could just as easily be provided in a doctor’s office. In other words, if the facility looks and acts like a doctor’s office, CMS may decide to reimburse it like a doctor’s office rather than an HOPD.

Physician Credentialing

  Who is qualified to practice hyperbaric medicine? UHMS succeeded in having Undersea and Hyperbaric Medicine (UHM) recognized as a subspecialty by the American Board of Medical Specialties with examinations sponsored by both the American College of Emergency Medicine and the American Board of Preventive Medicine.

  Now that the “grandfather” period is over by which physicians meeting certain criteria can become subspecialty board certified through testing, clinicians wishing to become subspecialty board certified in UHM must complete a one-year fellowship recognized by the American College of Graduate Medical Education (ACGME).

  Fewer than 600 physicians in the US have obtained UHM subspecialty board certification. With only a handful of ACGME fellowships, only a few physicians are added to their ranks each year. Most physicians currently practicing hyperbaric medicine have received only a 40-hour basic course in hyperbaric and diving medicine.

  Private payers have, in some regions, made UHM subspecialty board certification a requirement to be reimbursed for HBOT treatment supervision. MACs have begun to offer language requiring at the very least, a certificate of added qualification. Thus, both private payers and Medicare contractors have succeeded in developing increasingly detailed and/or restrictive requirements for physicians wishing to practice hyperbaric medicine, including, in some cases, the requirement that they be proctored for a certain number of HBOT treatments or patients. Independent Blue Cross and MVP (Mohawk Valley Physicians) Health Plan both have policies to that effect.

Physician Reimbursement

  Another question is that of level of “work” performed by the hyperbaric physician. At the request of CMS, the American Medical Association’s (AMA’s) Specialty Society RVS Update Committee (RUC) recently initiated a review of the physician supervision of HBOT. Hyperbaric chamber supervision is billed using the AMA’s Current Procedural Terminology (CPT®) code 99183.

  This code had never been surveyed by the RUC, and thus had simply been assigned a value of 2.34 relative value units (RVUs) by CMS.

  The RUC process is designed to assess the work that a physician performs for a given CPT code, in this instance 99183. There are three components that are addressed by the RUC to determine the proposed RVU value: physician work, practice expense, and professional liability insurance. The work is determined by the time it takes to perform the service; the technical, physical, and mental effort; the judgment involved; and the stress due to the potential complications that the patient may experience. The process includes a survey of physicians who perform the service. The pre-, intra-, and post-service time is estimated by the survey recipients, who are then asked to compare that to another code they are familiar with.

  As part of that evaluation, the RUC needed to understand how complicated hyperbaric patients tended to be in terms of their level of illness. The RUC requested that UHMS provide data on the average number of comorbid conditions present in hyperbaric patients, the 10 most common comorbid conditions, and the average number of medications taken per patient. In addition, as part of the assessment of work, the RUC wished to know the average number of patients supervised per day by a hyperbaric medicine physician in either a monoplace or a multiplace environment. Using the data available in the US Wound Registry (USWR), which also hosts the US Hyperbaric Registry, UHMS was able to provide the RUC with all the data the committee requested. The RUC also asked for data on the frequency and type of adverse events or “side effects” that patients experience during HBOT, data that the USWR also had available. (The top 10 comorbid conditions from the national dataset are available in Table 1.)

  The American College of Emergency Physicians requested expert assistance from UHMS in this process. The process to determine the RVUs for work and practice expense was rigorous and not without controversy. The AMA RUC has finalized its recommendation and submitted it to CMS. The CMS decision will most likely appear in the final rule in November. It is anticipated that physician reimbursement will go down. It is also likely that 99183 will be eligible for review within the next five years.

Medicare Preauthorization for HBOT

  CMS will begin implementing a prior authorization demonstration program for nonemergent hyperbaric oxygen therapy in Illinois, Michigan, and New Jersey.

  If prior authorization is not sought, claims will be on a 100% post-payment review. The conditions that will be available for prior authorization include preparation and preservation of compromised skin grafts, chronic refractory osteomyelitis, osteoradionecrosis, actinomycosis, and DFUs. There is a potential limitation of 36 HBOT “courses” per year. Since preauthorization decisions will be made on the initial requests within 10 business days and subsequent requests will be processed within 20 business days, the authorization process may delay the start of HBOT by two weeks. Many of these decisions are based on the outcomes of a supplemental medical review contract project for HBOT and Healthcare Common Procedure Coding System code C1300. This contract project reviewed both 99183 and C1300 in the outpatient hospital arena. They surveyed 2,000 claims with 146 unique providers in two MAC jurisdictions: Palmetto GBA and Novitas JL. More than 30% of providers did not respond to the request for information, and of those who did, 41% were denied. Total denials reached 58%.

  This outcome impacted the decision to initiate the prior authorization project. HBOT is plagued by poor responsiveness in the hyperbaric community to governmental inquiries, inadequate documentation, and a lack of cohesiveness when faced with these challenges.

Movement From Volume-Based Pay

  It is no secret that the cost of Medicare services is expected to exceed its budget within the next 2-5 years and that outpatient payments are the most out-of-control area of spending.

  High-cost therapies have been provided with no feedback mechanism linking cost to outcome or quality of care. In 2014, physicians who fail to report three quality measures through the Physician Quality Reporting System (PQRS) will see a 2% reduction in Medicare payment in 2016. Physicians who report nine PQRS measures in 2014 will see a 0.5% bonus.

  Since there were only two quality measures directly relevant to wound care (and those were poorly written), it was unlikely that a wound care provider could achieve the goal of reporting nine relevant quality measures. However, CMS launched a new program in January called the Qualified Clinical Data Registry (QCDR), which allows specialty societies to develop their own quality measures.

  The Alliance of Wound Care Stakeholders, in conjunction with the USWR, launched 12 wound care-specific quality measures, one of which is specifically focused on HBOT utilization. The UHMS quality measures subcommittee is developing more hyperbaric quality measures for 2015. The development of sound measures is vital because under the Affordable Care Act (“Obamacare”) a potentially large percentage of healthcare reimbursement will be linked to quality measures. CMS may move away from volume-based care by establishing outpatient diagnosis related groups (DRGs), through which the hospital would be reimbursed a set amount for a presenting problem or pay for “episodes of care.”

Potential Site-of-Service Adjustment

  In the current payment scenario, hospitals are reimbursed under an inpatient DRG per admission, but have been reimbursed under a fee-for-service model for outpatient services (Outpatient Prospective Payment System; OPPS). OPPS costs to the Medicare program have increased substantially in the last five years, mostly as a consequence of hospital acquisitions of physician practices.

  When a hospital acquires a physician practice, the procedures that are performed there may become an OPPS procedure and get reimbursed at outpatient hospital rates. This has resulted in a marked increase in Medicare costs for fairly common procedures such as cardiac echocardiography to CMS.

  The Medicare Payment Advisory Commission (MedPAC) recently recommended that Congress reduce or eliminate the Medicare reimbursement difference between HOPDs and freestanding physician practices.

  Although this initial recommendation is limited to 66 ambulatory payment classifications (APCs), the goal is to more closely mirror reimbursement when these services are provided in a freestanding physician office. This means the “provider-based payment” for some OPPS services will be changed. The provider-based payment system was initially created to reflect the increased cost that hospitals carried to provide these services, such as 24/7 availability. However, since these recently acquired services are being provided in what used to be a freestanding center, the extra cost basis does not exist in these settings.

  The MedPAC’s recommendation for site-neutral reimbursement for evaluation and management (E/M) codes was not included in the final work product that was signed into law in 2012. Although the APC for HBOT services is not on the current MedPAC APC list, HBOT has recently experienced a marked increase in the number of services provided. Should the APC for HBOT come up for evaluation, a significant “adjustment” in HBOT payment to affect “site neutrality” could shift HBOT services away from OPPS and into doctor’s offices. It is becoming increasingly obvious that the hyperbaric medicine community will need to band together to produce meaningful data that clearly demonstrate the positive effects of HBOT on patients and outcomes.

  To this end, UHMS has established a clinical practice guidelines (CPG) committee. Chaired by Enoch Huang, MD, this group has been tasked with evaluating the existing literature using the methodology developed by the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) Working Group to rate the level of quality of evidence.

  Under the guidance of Huang, the group has completed the first CPG for DFUs. It is the plan of the CPG committee to assess all UHMS accepted indications in this manner.

  The Quality, Utilization, Authorization, and Reimbursement committee (QUARC) co-chaired by the authors of this article is tasked with monitoring the changes that are occurring in policy both nationally and internationally.

  QUARC is asking all practicing hyperbaric physicians to be observant to changes in local coverage policy and to alert QUARC immediately. Without constant surveillance and monitoring, keeping abreast of changes is extremely difficult. Many times, the local physicians are the first to be aware of these changes, and so QUARC is requesting that frontline physicians be aware and involved in these monitoring efforts.

  HBOT positively impacts the quality of life of patients, provides invaluable improvements in outcomes and must remain a viable option for clinicians in the future. In order to accomplish this, we need to work cooperatively for the future of the specialty.

Helen Gelly is emeritus medical director of Hyperbaric Physicians of Georgia and chief executive officer of HyperbaRXs.

Caroline E. Fife is chief medical officer at Intellicure Inc.; executive director of USWR; medical director of St. Luke’s Wound Clinic, The Woodlands, TX; and co-chair of the Alliance of Wound Care Stakeholders.


1. Gabb G, Robin ED. Hyperbaric oxygen: A therapy in search of diseases. CHEST Journal. 1987;92(6):1074-1082.

2. Phillips TJ. Hyperbaric oxygen therapy: A therapy in search of a disease? Dermatologic Surgery. 2000;26(12):1167-1170.

Helen Gelly, MD, FACCWS, UHM/ABPM, FUHM & Caroline E. Fife, MD, FAAFP, CWS
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