Wait what? Hyperbaric oxygen therapy involves delivering oxygen at higher than atmospheric pressure for a certain time period. It is used to treat a variety of medical conditions ranging from the bends to gas grene to carbon moxonide poisoning to osteoradionecrosis of the jaw. It consists of patients undergoing ‘dives’. A dive means receiving 100% Oxygen at 2.4 atm for 90 minutes. The question as to whether HBO therapy is beneficial in preventing ORN is debatable.
To dive
Wait, let’s backtrack. So, the theory of delivering HBO to patients prior to receiving head and neck radiation was proposed by Marx who believed ORN resulted from hypoxia, hypocellularity and hypovascularity. When it comes to diving, the protocol is 20 dives before receiving radiation therapy and 10 dives after receiving radiation therapy. And traditionally, HBO is prescribed for patients who receive 50 Gray or greater. Why undergo HBO? HBO increases oxygen tensions in hypoxic tissues such as burns, is associated with angiogenesis (new blood vessel formation), fibroblast proliferation and collagen synthesis.
Not to dive
This sounds great. What’s the catch? The studies that have documented HBO have been uncontrolled and found recovery rates of 15%-45% with HBO alone. There have been no double-blind controlled, randomized studies that have illustrated a significant difference in improvement with HBO. Additionally, Marx’s original study on HBO was also not double blind. Additionally, HBO has not been found to promote angiogenesis in dead bone. Thus, although, it may encourage new blood vessel formation in soft tissue, it has not been shown to promote blood vessel growth in bone.
Further reading
Chuang, Sung-Kiang. “Limited Evidence to Demonstrate That the Use of Hyperbaric Oxygen (HBO) Therapy Reduces the Incidence of Osteoradionecrosis in Irradiated Patients Requiring Tooth Extraction.”Journal of Evidence Based Dental Practice 11.3 (2011): 129-31. Web.
