Hyperbaric Oxygen Therapy to Treat Diabetes Impaired Wound Healing in Rats

Abstract

Wound healing in diabetes is frequently impaired and its treatment remains a challenge. Hyperbaric oxygen therapy (HBOT) receives a wide attendance and is often used as a last resort treatment option, however, its effectiveness for many conditions is unproven. We tested the effect of HBOT on healing of diabetic ulcers in an animal experimental setting. Experimental diabetes was induced by intraperitoneal injection of streptozotocin. Four weeks after diabetes induction, rats were ulcerated by clamping a pair of magnet disks on the dorsal skin for 16 h. After magnet removal, the animals received HBOT, daily on weekdays, for 4 weeks. To examine the effect of HBOT on diabetes impaired wound healing, the degree of wound tissue perfusion, inflammation, angiogenesis, and tissue breaking strength were evaluated. HBOT effects on the degree of inflammation and number of blood vessels could not be observed. HBOT improved the tissue breaking strength of the wound, however, this did not reach statistical significance. Twenty hours after ending the HBOT, a significantly improved oxygen saturation of the hemoglobin at the venous end of the capillaries and the quantity of hemoglobin in the micro-blood vessels was measured.

Oxygen therapies and their effects on wound healing

“…Eleven experimental studies evaluated the efficacy of HBOT on wound healing. To examine the effects of HBOT in wound healing impaired by diabetes, Tuk et al evaluated the degree of wound tissue perfusion, inflammation, angiogenesis, and tissue breaking strength in a diabetic rat model . No effects on the degree of inflammation and number of blood vessels could be observed.…”

“…No effects on the degree of inflammation and number of blood vessels could be observed. The tissue breaking strength improved, but did not reach statistical significance . Only the quantity of hemoglobin in micro‐blood vessels was significantly increased as well as the oxygen saturation of the hemoglobin at the venous end of the capillaries .…”

Effects of hyperbaric oxygen therapy on uncomplicated incisional and open wound healing in dogs

“…The use of HBOT as a treatment for complicated wounds in man, such as diabetic ulcers, compromised skin grafts, thermal burns, and acute burn or crush injury wounds, has been well documented and found to improve healing effectively . There is limited research published on its use in animals, with some reporting a benefit on granulation tissue and wound size, whereas others report no effect …”

“…Investigative evidence regarding the efficacy of this therapy for any type of wound healing in dogs is lacking; however, recent data have been published on its safety and physiologic effects of improved tissue and arterial and transcutaneous oxygenation . Currently, use of HBOT as an adjunct to any wound healing in dogs is based on subjective or anecdotal evidence evaluating complicated wounds in dogs, and research studies evaluating complicated wounds in rabbits, rats, and man . The major deficit in the veterinary literature is the lack of prospective, randomized evaluations of the effects of HBOT on wound healing in dogs.…”

“…The major deficit in the veterinary literature is the lack of prospective, randomized evaluations of the effects of HBOT on wound healing in dogs. The most commonly evaluated models with prospective evaluation are in rats or rabbits in which a systemic state was experimentally induced, which could impair healing of wounds (diabetes, hyperglycemia, and snake envenomation), or the wounds were created to be ischemic . No experimental controlled models for wound healing that evaluate systemically healthy versus abnormal states or complicated versus uncomplicated wound healing have been created in dogs.…”