Effect of hyperbaric oxygen on the growth and development of medicinal maggots

Some wound care therapists use both maggot debridement therapy (MDT) and hyperbaric oxygen (HBO2) therapy to treat non-healing wounds. Some practitioners have reported success using both MDT and HBO2 therapy concurrently; others have not. To begin evaluating the utility of using MDT and HBO2 therapy concurrently, we assessed the effects of hyperbaric oxygen (HBO2) on maggot growth and development, as a surrogate for debridement capacity. Replicate sets of medical-grade blowfly larvae were placed on liver-agar wound models and exposed to HBO2 at 2.0 atmospheres absolute (atm abs) for 90 minutes on 0 (control), 1, 2 or 3 sequential days. The effects of HBO2 exposure were quantified by measuring the maggots' subsequent growth and development. Exposure to HBO2 was most lethal to young larvae (second instars), but not to older larvae (third instars). There was no dose-relationship between the number of HBO2 treatments and rate of larval survival. Our findings suggest that maggot therapy and HBO2 therapy may be administered concurrently, as long as the larvae are not too immature (that is, as long as they are beyond the second instar) by the time they take their first dive. A clinical trial evaluating the clinical benefits of concurrent HBO2 therapy and MDT is warranted.