Application of Hyperbaric Oxygen Therapy (HBOT) as a Healing Aid after Extraction of Incisors in the Equine Odontoclastic Tooth Resorption and Hypercementosis syndrome

Hyperbaric Oxygen Therapy (HBOT) is a stress-free, relatively safe method supporting the treatment of many different diseases. Although it is widely used in human medicine (including dentistry), in veterinary medicine, especially in the treatment of horses, there are not many scientifically described and documented cases of its use. Equine Odontoclastic Tooth Resorption and Hypercementosis syndrome is a disease that affects older horses and significantly reduces their quality of life. The only effective treatment for this condition is extraction of the incisors. The described case compares the recovery process of the alveolar area after extraction of incisors during the course of EOTRH syndrome without and with the use of a chamber, in horses with the same clinical picture of the disease, of the same age, and living in the same conditions. According to the authors’ knowledge, the presented case describes the use of a chamber in equine dentistry for the first time.

Treatment of a Chronic Vulvar Wound by Hyperbaric Oxygen Therapy (HBOT)

We hereby report the case of a 66-year-old obese patient (BMI 30) with type 2 diabetes, who presented a chronic vulvar lesion on the left labia majora following surgical drainage of an abscess. After multiple unsuccessful treatments by antibiotics and local wound care, we proposed a trial of hyperbaric oxygen therapy (HBOT). The patient fully recovered after 54 sessions at 2.5 ATA, 95 minutes each. HBOT has been studied for perineal lesion such as skin atrophy or necrosis caused by irradiation but not for vulvar nonhealing chronic lesions in the case of impaired vascularization caused by diabetes. This case is, to our knowledge, one of the first publications about the healing boost of HBOT in chronic vulvar wounds due to vascular impairment.

Seizures Caused by Exposure to Hyperbaric Oxygen in Rats Can Be Predicted by Early Changes in Electrodermal Activity

Hyperbaric oxygen (HBO2) is breathed during undersea operations and in hyperbaric medicine. However, breathing HBO2 by divers and patients increases the risk of central nervous system oxygen toxicity (CNS-OT), which ultimately manifests as sympathetic stimulation producing tachycardia and hypertension, hyperventilation, and ultimately generalized seizures and cardiogenic pulmonary edema. In this study, we have tested the hypothesis that changes in electrodermal activity (EDA), a measure of sympathetic nervous system activation, precedes seizures in rats breathing 5 atmospheres absolute (ATA) HBO2. Radio telemetry and a rodent tether apparatus were adapted for use inside a sealed hyperbaric chamber. The tethered rat was free to move inside a ventilated animal chamber that was flushed with air or 100% O2. The animal chamber and hyperbaric chamber (air) were pressurized in parallel at ~1 atmosphere/min. EDA activity was recorded simultaneously with cortical electroencephalogram (EEG) activity, core body temperature, and ambient pressure. We have captured the dynamics of EDA using time-varying spectral analysis of raw EDA (TVSymp), previously developed as a tool for sympathetic tone assessment in humans, adjusted to detect the dynamic changes of EDA in rats that occur prior to onset of CNS-OT seizures. The results show that a significant increase in the amplitude of TVSymp values derived from EDA recordings occurs on average (±SD) 1.9 ± 1.6 min before HBO2-induced seizures. These results, if corroborated in humans, support the use of changes in TVSymp activity as an early “physio-marker” of impending and potentially fatal seizures in divers and patients.

Necrotic Wound Caused by Jararaca (Bothrops jararaca) in a Dog - Hyperbaric Oxygen Therapy (HBTO)

Background: Snakebites are the main responsible for envenoming in dogs and the bothropic venom remains the most common in Brazil, which can induce a necrotic skin wound. Hyperbaric oxygen therapy (HBOT) use 100% oxygen under high pressure and used to treat different wounds in human patients. To the authors’ knowledge, no reports regarding to use the HBOT in skin wound caused by snakebite (Bothrops jararaca) are present in the literature. The present clinical case aimed to describe the use of HBOT for the treatment of an extensive necrotic wound caused by jararaca snakebite in a dog.Case: A neutered 8-year-old mixed-breed dog, weighing 12 kg, was admitted with a 7-day history of extensive necrotic wound was identified in the face and neck causing by a snakebite, and no sign of pain. The procedure of HBOT (single sessions of 1.5 ATM, 45 min, repeated every 48 h, up to 12 sessions) was decided, and the complete blood cells, alanine aminotransferase, creatinine, creatine kinase, prothrombin time, activated partial thromboplastin time, wound clinical evaluation were measured at the following time-points: 2nd, 5th, 10th, and 12th sessions. At the 5th session was identified leukopenia, neutropenia and lymphopenia. Wound re-epithelialization was initiated after the 5th session, and the complete epithelialization was identified at the 12th session of HBOT. During the HBOT no side effects were identified. Three months after the HBOT finished, the animal returned to the clinic and the clinical status evolved positively, and the wound was completed healed.Discussion: This report described the treatment of an extensive necrotic skin wound caused by snakebite (Bothrops jararaca) in an 8-year-old, neutered, mixed-breed dog using the HBOT. The wound healing was achieved after 12 sessions, similar to the literature, which reported a ranging from 1 to 12 sessions. The HBOT protocol used in this case was similar as reported for human patients with chronic wounds due to the lack of HBOT protocols for animals. No reports regarding the use of HBOT for treat necrotic wound caused by snakebite was described in the literature, and to the authors’ knowledge, this is the first report in Brazil describing the use of HBOT in dogs. On the other hand, dogs with surgically induced skin wounds and treated with daily session of HBOT using the treatment protocol of 1.7 ATM (30 min) and 2.0 ATM (40 min) up to 7th day of treatment did not show significant results on healing [9]. This fact was associated with the HBOT achievement in the proliferative and remodeling phases of the healing process. The high intensity of HBOT was between the 5th and 10th session since the wound showed a higher area decrease rate and consequently increase of wound contraction. This period was corresponding to the 10th and 20th day of the healing process, which can be identified angiogenic activity, re-epithelialization, and collagen maturation. The decrease in PVC has been associated with the anticoagulant and/or hemorrhagic activity caused by the venom, and leukopenia, neutropenia and lymphopenia was related with possible bone marrow exhaustion. Single sessions of HBOT (1.5 ATM, 45 min, and repeat each 48 h, up to 12 session) induces healing of necrotic wound caused by snakebite (Bothrops jararaca) in an 8-year-old, neutered, mixed-breed dog without any side effects.Keywords: dog, healing, hyperbaric chamber, skin wound, snake.