Utilization guidelines are presented relative to specific treatment conditions and include criteria for diagnosis:
Acute carbon monoxide intoxication: Chamber compressions should be between 2.5 and 3.0 atmospheres absolute (ATA). Patients with persistent neurological dysfunction may require subsequent treatments within six to eight hours, continuing once or twice daily until there is no further improvement in cognitive functioning.
Decompression illness (gas bubbles in tissue or blood in volumes sufficient enough to interfere with the function of an organ or to cause alteration in sensation) resulting from rapid decompression during ascent presents clinical manifestations ranging from skin eruptions to shock and death. Treatment of choice for decompression illness is HBO therapy with mixed gases. The result is immediate reduction in the volume of bubbles. The treatment prescription is highly variable and case specific. The depths could range between 60 to 165 feet of sea water for durations of 1.5 to over 14 hours. The patient may or may not require repeat dives.
Gas embolism occurs when gases enter the venous or arterial vasculature embolizing in a large enough volume to compromise the function of an organ or body part and results in ischemia to the affected areas. HBO therapy, the treatment of choice, is most effective when initiated early. Therapy is directed toward reducing the volume of gas bubbles and increasing the diffusion gradient of the embolized gas. Treatment modalities range from high pressure to low pressure mixed gas dives.
Clostridial myositis and myonecrosis (gas gangrene) is an acute, rapidly growing invasive infection of the muscle characterized by profound toxemia, extensive edema, massive death of tissue and variable degree of gas production. The diagnosis of gas gangrene is based on clinical data supported by a positive gram-stained smear or culture obtained from tissue fluids. X-ray radiographs, if obtained, can visualize tissue gas. The onset of gangrene can occur one to six hours after injury and presents with severe and sudden pain at the infected area. The skin overlying the wound progresses from shiny and tense, to dusky, then bronze in color. Hemorrhagic vesicles may be noted. A thin, sweet-odored exudate is present. Swelling and edema occur. The noncontractile muscles progress to dark red to black in color. The goal of HBO therapy is to stop alpha-toxin production thereby inhibiting further bacterial growth at which point the body can use its own host defense mechanisms. HBO treatment starts as soon as the clinical picture presents and is supported by a positive gram-stained smear. A treatment approach utilizing HBO, is adjunct to antibiotic therapy and surgery. Initial surgery may be limited to opening the wound. Debridement of necrotic tissue can be performed between HBO treatments when clear demarcation between dead and viable tissue is evident. The usual treatment consists of oxygen administered at 3.0 ATA pressure for 90 minutes three times in the first 24 hours. Over the next four to five days, treatment sessions twice a day are usual.
Crush injuries and suturing of severed limbs, acute traumatic peripheral ischemia (ATI), and acute peripheral arterial insufficiency associated with arterial embolism and thrombosis: Acute traumatic ischemia is the result of injury by external force or violence compromising circulation to an extremity. The extremity is then at risk for necrosis or amputation. Secondary complications are frequently seen: infection, non-healing wounds, and non-united fractures. The goal of HBO therapy is to enhance oxygen at the tissue level to support viability. When tissue oxygen tensions fall below 30mm Hg., the body’s ability to respond to infection and wound repair is compromised. Using HBO at 2-2.4 ATA, the tissue oxygen tension is raised to a level such that the body’s responses can become functional again. The benefits of HBO therapy for this indication are:
-increased oxygen delivery per unit of blood flow or enhanced tissue oxygenation,
-edema reduction and
-reduction in the complication rates for infection, nonunion and amputation. The usual treatment schedule is three 1.5 hour treatment periods daily for the first 48 hours. Additionally, two 1.5 hour treatment sessions daily for the next 48 hours may be required. On the fifth and sixth days of treatment, one 1.5 hour session would typically be utilized. At this point in treatment, outcomes of restored perfusion, edema reduction and either demarcation or recovery would be sufficient to guide discontinuing further treatments. For acute traumatic peripheral ischemia, crush injuries and suturing of severed limbs, Hyperbaric Oxygen Therapy is a valuable adjunctive treatment to be used in combination with accepted standard therapeutic measures, when loss of function, limb, or life is threatened. Arterial insufficiency ulcers may be treated by HBO therapy if they are persistent after reconstructive surgery has restored large vessel function.
-The principal treatment for progressive necrotizing infections (necrotizing fasciitis) is surgical debridement and systemic antibiotics. HBO therapy is recommended as an adjunct only in those settings where mortality and morbidity are expected to be high despite aggressive standard treatment. Progressive necrotizing fasciitis is a relatively rare infection. It is usually a result of a group A streptococcal infection beginning with severe or extensive cellulitis that spreads to involve the superficial and deep fascia, producing thrombosis of the subcutaneous vessels and gangrene of the underlying tissues. A cutaneous lesion usually serves as a portal of entry for the infection, but sometimes no such lesion is found. The histologic hallmark is extensive inflammation and necrosis of the subcutaneous fat, fascia and muscle. Numerous polymorphonuclear leukocytes and mononuclear cells are present in the upper layers of the dermis. Hyperbaric oxygen may be a beneficial adjunct for a subset of patients with anaerobic gram negative necrotizing fasciitis.
-The recommended HBO treatment protocol is 90 minutes at 2.5 ATA every 8 hours for the first day and then twice daily for a total or maximum of 10 treatments.
Preparation and preservation of compromised skin grafts utilizes HBO therapy for graft or flap salvage in cases where hypoxia or decreased perfusion have compromised viability. This indication is not for primary management of wounds. HBO therapy enhances flap survival. Treatments are given at a pressure of 2.0 to 2.5 ATA lasting from 90-120 minutes. It is not unusual to receive treatments twice a day. When the graft or flap appears stable, treatments are reduced to daily. Should a graft or flap fail, HBO therapy may be used to prepare the already compromised recipient site for a new graft or flap. It does not apply to the initial preparation of the body site for a graft. HBO therapy is not necessary for normal, uncompromised skin grafts or flaps. Medicare coverage does not apply to artificial skin grafts.
Chronic refractory osteomyelitis persists or recurs following appropriate interventions. These interventions include the use of antibiotics, drainage of the abscess, immobilization of the affected extremity, and surgical debridements with removal of the sequestrum. HBO therapy is an adjunctive therapy used with the appropriate antibiotics and surgical debridement to eliminate the dead bone. HBO treatments are delivered at a pressure of 2.0 to 2.5 ATA for a duration of 90-120 minutes. It is not unusual to receive daily treatments following major debridement surgery. The number of treatments required vary on an individual basis. Medicare can cover the use of HBO therapy for chronic refractory osteomyelitis that has been shown to be unresponsive to conventional medical and surgical management.
HBO’s use in the treatment of osteoradionecrosis and soft tissue radionecrosis is one part of an overall plan of care that also includes debridement or resection of nonviable tissue in conjunction with antibiotic therapy. Soft tissue flap reconstruction and bone grafting may also be indicated. HBO treatment can be indicated in the preoperative and postoperative management of existing osteoradionecrosis or soft tissue radionecrosis. HBO therapy must be utilized as an adjunct to conventional therapy. The patients who suffer from soft tissue damage or bone necrosis present with disabling, progressive, painful tissue breakdown such as wound dehiscence, infection, tissue loss and graft or flap loss. The goal of HBO treatment is to increase the oxygen tension in both hypoxic bone and tissue to stimulate growth in functioning capillaries, fibroblastic proliferation and collagen synthesis. The recommended daily treatments last 90-120 minutes at 2.0 to 2.5 ATA. The duration of HBO therapy for these patients is highly individualized.
Coverage for osteoradionecrosis of the jaw is limited to cases with evidence of overt fracture or bony resorption. HBO is not covered to prepare the patient for dental extraction in order to prevent the development of osteoradionecrosis.
Cyanide poisoning carries a high risk of mortality. Victims of smoke inhalation frequently suffer from both carbon monoxide and cyanide poisoning. The traditional antidote for cyanide poisoning is the infusion of sodium nitrite. This treatment can potentially impair the oxygen carrying capacity of hemoglobin. Using HBO therapy as an adjunct therapy adds the benefit of increased plasma dissolved oxygen. HBO’s benefit for the pulmonary injury related to smoke inhalation remains experimental. The HBO treatment protocol is to administer oxygen at 2.5 to 3.0 ATA for up to 120 minutes during the initial treatment. Most patients with combination cyanide and carbon monoxide poisoning will receive only one treatment.
Actinomycosis is a bacterial infection caused by Actinomyces israelii. Its associated findings include slow growing granulomas that later break down, discharging viscid pus containing minute yellowish granules. The treatment includes prolonged administration of antibiotics (penicillin and tetracycline). Surgical incision and draining of accessible lesions is also helpful. Only after the disease process has been shown refractory to antibiotics and surgery, could HBO therapy be covered by Medicare. HBO therapy must be utilized as an adjunct to conventional therapy.
Treatment of diabetic wounds of the lower extremities in patients who meet all three (3) of the following criteria:
- Patient has type I or type II diabetes and has a lower extremity wound that is due to diabetes; and
- Patient has a wound classified as Wagner grade III or higher (Grade 2 – ulcer penetrates to tendon, bone or joint; Grade 3 – lesion has penetrated deeper than grade 2 and there is abscess, osteomyelitis, pyarthrosis, plantar space abscess, or infection of the tendon and tendon sheaths; Grade 4 – gangrene of the forefoot; Grade 5 – gangrene of the entire foot); and
- Patient has failed an adequate course of standard wound therapy. The use of HBO therapy will be covered as adjunctive therapy only after there are no measurable signs of healing for at least 30 days of treatment with standard wound therapy and must be used in addition to standard wound care. Standard wound care in patients with diabetic wounds includes:
- Assessment of a patient’s vascular status and correction of any vascular problems in the affected limb if possible,
ii. Optimization of nutritional status,
iii. Optimization of glucose control,
iv. Debridement by any means to remove devitalized tissue,
v. Maintenance of clean, moist bed of granulation tissue with appropriate moist dressings,
vi. Appropriate off-loading, and
vii. Necessary treatment to resolve any infection that might be present.
Failure to respond to standard wound care occurs when there are no measurable signs of healing for at least 30 consecutive days. Wounds must be evaluated at least every 30 days during administration of HBO therapy. Continued treatment with HBO therapy is not covered if measurable signs of healing have not been demonstrated within any 30-day period of treatment. Failure of transcutaneous oxygen measurements to demonstrate adequate local blood flow with which to effect improvement, when treating diabetic wounds of the lower extremities, will result in the HBO treatments to be considered not medically necessary.
NOTE: As with #8 above, standard therapy for osteomyelitis includes surgical debridement/excision of the infected nidus of bone.