A randomised controlled trial of hyperbaric oxygen to prevent osteoradionecrosis of the irradiated mandible
Osteoradionecrosis subsequent to a surgical procedure in an irradiated mandible
Arm 1: Standard management: 1. Pre- and post-operative chlorohexidine1 mouthwash 0.2% - use 10 ml (i.e. one capful) washed around the mouth for around 1 minute and spat out, three times daily for 5 days post-operatively. 1.1. In case of chlorohexidine allergy use warm salt mouthwash at 1 teaspoon per cup of warm water. 2. Oral antibiotics: amoxicillin 3 g oral 1 hour pre-operatively (or 1 g intravenously), and 250 mg three times a day (tds) x 5 days post-operatively 2.1. In penicillin allergy: Orally either 600 mg tablet, or same dose of 75 mg/5 ml suspension if tablets not tolerated, 1 hour pre-operatively or intravenously 600 mg at time of surgery, and 200 mg metronidazole (patients should be warned of interaction between alcohol and metronidazole) tds x 5 days post-operatively Arm 2: Standard management plus HBO Patients will undergo 20 HBO treatments prior to surgery followed by a further 10 HBO treatments. HBO will comply with dive table RN66. For each HBO treatment, patients are compressed to 2.4 ata while sitting in an appropriate British Hyperbaric Association recognised hyperbaric chamber. Patients breathe 100% oxygen at pressure via a transparent hood. The total time at 2.4 ata is 90 minutes. During the final 10 minutes of oxygen breathing, the chamber is depressurised to ambient atmospheric pressure at a linear rate (14.3 kpa/min). 3. All participants will be operated with a minimally traumatic surgical technique after the standard management with or without HBO.
1. Both males and females, age >18 years 2. Prior history of external beam radiotherapy (dose >50 Gy) to mandible or prior history of brachytherapy with equivalent radiation dose as above 3. No evidence of cancer recurrence 4. Condition requiring surgery to mandible (commonest examples but not limited to: dental extraction, implant placement, surgical tooth, cyst or osteosynthesis plate removal) 5. Patient has read and understood information leaflet and is willing to be randomised 6. Patient competent to consent and psychologically/ physically fit for HBO
1. Known contraindications to HBO: 1.1. Lung disease: Severe chronic obstructive airways disease; bullous lung disease, acute or chronic pulmonary infection; uncontrolled asthma, untreated pneumothorax 12. Middle ear disease (such as previous middle ear operations, eustachian tube dysfunction or recurrent attacks of vertigo) that proves refractory to simple interventions such as grommet insertion 2. Prior hyperbaric oxygen therapy 3. Prior diagnosis of osteoradionecrosis of the mandible 4. Previous surgery for osteoradionecrosis 5. Any history of systemic bisphosphonate therapy, pentoxyphylline or tocopherol 6. Pregnancy