The initial effect of hyperbaric oxygen therapy is to increase the oxygen pressure and reduce the volume of the bubble, so the oxygen-carrying capacity of the blood increases, and then the oxygen content that diffuses into the tissue increases. Relevant literature shows that tissue oxygen partial pressure can be increased by 10% within 3 hours.
Reducing bubble volume is important in veterinary hyperbaric oxygen therapy because the thickness of occluding material or air embolism in the vessel can be mechanically reduced, making it easier for smaller bubbles to pass through the vessel.
In addition, reduced bubble surface area also reduces activation of platelet and release of factor VII.
Other benefits of veterinary hyperbaric oxygen therapy include increasing the oxidative killing capacity of white blood cells, modulating the production of nitric oxide, and modulating growth factors and cytokines by affecting receptors.
Veterinary hyperbaric oxygen therapy reduces clostridial toxins and is synergistic with quinolones, amphotericin B, and aminoglycoside antibiotics, which all require oxygen to cross cell membranes.
In addition, veterinary hyperbaric oxygen therapy has a clear effect on reducing angioedema, although the specific mechanism is not fully understood.
It may be because the oxygen supply to normal tissues increases when hyper oxygenated blood vessels constrict, but the blood supply to ischemic tissues does not change.
Compared with human medicine, the literature research on hyperbaric oxygen in animal hospitals and veterinary medicine is much less, but the application amount is gradually increasing.
As early as 2000, a study of 1,400 cats and dogs found that hyperbaric oxygen has an effect on sepsis, peritonitis, osteomyelitis, meningitis, spinal cord injury, and swelling caused by snake bites. In addition, veterinary hyperbaric oxygen therapy also has a good effect on arterial thrombosis.
Hyperoxia has also been shown to be effective in treating ischemic injuries, such as arterial thrombosis, gastric dilatation-torsion, traumatic brain injury, shock, and symptoms after CPR.
It has been confirmed in the literature that increasing the oxygen pressure gradient in and around the injured tissue can promote angiogenesis and increase the proliferation of fibroblasts.
Therefore, veterinary hyperbaric oxygen therapy may be effective for treating difficult-to-heal wounds, skin flaps, radiation injuries, etc., and may have some effect on treating sepsis, osteomyelitis, gangrene, and fungal infection. It can also enhance the lethality of leukocytes, play the synergistic effect with antibiotics, and inhibit the production of clostridial toxins.
In addition, high oxygen levels can improve growth factors and cytokines, helping to improve inflammatory environments such as pancreatitis, cardiogenic shock, and toxin circulation.