Normobaric Oxygen Therapy: An Alternative Technique for Treating Gas Embolism in Sea Turtles
Abstract
Gas embolism (GE) and subsequent decompression sickness (DCS) have been recently described in bycaught sea turtles after entrapment at depth.1 In moderate and severe cases, this condition can be lethal.1–3 Recommended treatment consists of hyperbaric oxygen therapy (HBOT) for up to 16 h at 2,8 ATA.4 However, most rehabilitation centers do not have access to the necessary hyperbaric chambers to apply the therapy. We propose an alternative treatment regime under normobaric oxygen (1 ATA) using a sealed container connected to a regular oxygen concentrator producing 1,5–2 l/min. Oxygen rich environment (>95%) facilitates elimination of nitrogen from the patient and tissue reoxygenation through passive diffusion.5 Normobaric therapy requires longer exposure times for full resolution of gas embolism, with treatment time regimes that can last more than 72 h depending on the amount and distribution of accumulated nitrogen bubbles present in the patient. Complementary emergency treatment completed the therapeutic plan. All turtles affected with GE and treated with normobaric oxygen (n=14) recovered from the disease and survived to be released back into the ocean. However, extended time for resolution of embolism in normobaric versus hyperbaric oxygen therapy could induce further tissue damage and greater risk of after-effects.4 Normobaric oxygen treatment seems to be an alternative technique to treat decompressed sea turtles when hyperbaric chamber is not available.
Acknowledgements
The authors wish to thank the Oceanografic staff for their efforts in caring for the animals and particularly the Mediterranean team of aquarists in charge of the sea turtles at the rehabilitation center. We also thank the Conselleria de Agricultura, Desarrollo Rural, Emergencia Climática y Transición Ecológica for their support.
Literature Cited
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