THERMAL BURNS
The burn wound is a complex and dynamic pathophysiologic process characterized by a zone of coagulation, surrounded by a region of stasis, bounded by an area of hyperemia. An intense inflammatory reaction leading to rapid edema formation, increased microvascular permeability, and sluggish blood flow, results in thrombosis, ischemia, and advancing necrosis. The basic problems in repair of burns include susceptibility to infection, prolonged healing, and excessive scarring. These problems are greatly increased due to the loss of the integumentary barrier and compromised or obstructed microvasculature. This prevents humeral and cellular elements from reaching the burned tissue, as well as delayed regeneration and healing.
RATIONALE: A significant body of data clearly supports the efficacy of hyperbaric oxygen in the treatment of thermal injury. A reduction in fluid requirements, less conversion of partial to full thickness injury, preservation of marginally viable tissue, improved microcirculation, reduction in edema, faster epithelialization, less inflammatory response, enhancement of PMN killing, preservation of tissue creatine phosphate, adenosine triphosphate, and decreased wound lactate have all been reported. A significant reduction in hospital stay and cost of treatment, noted when comparing patients treated with adjunctive hyperbaric oxygen therapy with those who did not, has also been reported. Hyperbaric oxygen therapy used as an adjunct to traditional burn care demonstrates greatest effects when initiated within the first 4 hours following the injury, or as quickly as possible.
SOURCE: UHMS Publication CR(HBO) 1996
RADIATION TISSUE DAMAGE (Osteoradionecrosis)
Patients must be treated in close coordination with referring physicians. Hyperbaric oxygen therapy must be part of an overall plan in which debridement, resection of involved bone, bone grafting, myocutaneous flap reconstruction, and specific antibiotic therapy are included. Pre- and postoperative hyperbaric oxygen is indicated to achieve a resolution.
RATIONALE: At some time after irradiation for therapy of malignancies, a small percentage of patients develop disabling, painful, and potentially fatal tissue breakdown. The basic physiology of this process is a progressive obliterative endarteritis with resultant tissue ischemia. In soft tissue radionecrosis, newer reconstructive techniques often allow total excision of the involved area with repair by vessel-bearing myocutaneous flaps. In some cases, however, particularly the mandible and maxilla, total surgical ablation would be disfiguring and reconstruction impossible. Hyperbaric oxygen therapy for radiation-damaged tissue was introduced in the early 1970's. With daily elevation of oxygen tension in hypoxic, hypocellular, and hypovascular bone and soft tissue near regions of functioning capillaries, fibroblast proliferation, collagen synthesis, and angiogenesis proceed. The killing ability of hypoxic leukocytes is enhanced with the elevation of tissue oxygen tensions. Preoperative hyperbaric oxygen prepares a vascular, noninfected wound to enable the surgeon to successfully debride and later reconstruct such entities. Unplanned but required surgery in previously irradiated tissue has an increased incidence of complications. Adjunctive hyperbaric oxygen therapy is indicated postoperatively in this clinical setting.
SOURCE: UHMS Publication CR (HBO) 1996