Hyperbaric Oxygen Therapy
Definition of Hyperbaric Oxygen Therapy
Hyperbaric Oxygen Therapy (HBOT) is a treatment where patients breath near 100 percent oxygen in a pressurized environment greater than sea level atmospheric pressure.
Therapeutic Mechanisms of Hyperbaric Oxygen Therapy
Hyperoxygenation HBO therapy provides immediate support to poorly-perfused tissue in areas of compromised blood flow. The increased pressure produced in a hyperbaric chamber results in a 10-15 fold increase in plasma oxygen concentration thus produces a four-fold increase in the diffusing distance of oxygen from functioning capillaries.
Neovascularization
Therapeutic effects of HBO therapy also include enhanced fibroblast division, neoformation of collagen, and capillary angiogenesis in areas of sluggish neovascularization such as late radiation damaged tissue, refractory osteomyelitis and chronic ulcerations in soft tissue.
Mechanical Effect of Direct Pressure
By utilizing the concept of Boyle’s Law, HBO therapy reduces the volume of intravascular or other free gases. This effect has established the basis for HBO therapy as the standard of care for decompression sickness and arterial gas embolism.
Vasoconstriction
Hyperoxia-induced vascular constriction is another important mechanism. HBO therapy can decrease blood flow in normal tissue by 20% and reduce edema by 20%.
Antimicrobial Effect
HBO therapy causes toxin inhibition and toxin inactivation in Clostridia perfringens infections (gas gangrene). Hyperoxygenation enhances phagocytes and white cell oxidative killing, and it has also been shown to enhance aminoglycocide activity. Recent research has demonstrated a prolonged post-antibiotic effect when HBO therapy is combined with tobramycin against pseudomonas aeroginosa.
Attenuation of Perfusion Injury
This is the most recently discovered benefit of HBO therapy. Much of the damage associated with reperfusion is brought about by the inappropriate activation of leukocytes. HBO therapy can prevent such an inappropriate activation of leukocytes, which in turn, preserves tissues that may otherwise be lost to ischemic reperfusion injury.
Conditions for Hyperbaric Oxygen Therapy (Model A1)
There are currently 15 conditions approved by CMS (Medicare) for human HBOT. The use of HBOT in these conditions has been proven to be very effective. Some of these conditions, as well as many others, have been shown to also benefit veterinary patients. These conditions include, but are not limited to the following:
- Abscesses
- Crush Injuries
- Spider and Snake bites
- Enhancement of Healing in Compromised Wounds
- Exceptional Blood Loss
- Necrotizing Soft Tissue Infections
- Smoke Inhalation/CO Toxicity
- Skin Grafts and Flaps (Compromised)
- Thermal Burns
- Ischemic Syndromes
- Pre and Post Spinal and Orthopedic Surgical Cases
- Head Trauma
- Pancreatitis
- And much more!!
Case Studies
Case Study #1
- 12 Year old cat with mild to moderate kidney disease
- Presented with infected bite wound, necrotic and had maggots
- Wound was debrided surgically to remove necrotic tissue
- Also treated with systemic antibiotics and topical medications and bandaging
- Treated with a total of 17 HBO Treatments
Resource: Emmek Hefer Small Animal Veterinary Hospital, Israel. VHMS
Before HBOT
After HBOT
Case Study #2 – Snake Bite
Yorkie Terrier with snake bite on face
- 36 hours after insult and prior to 2nd HBOT
- After 3 HBOT over 3 days
Recourse: Veterinary Wellness Center Lexington, KY. VHMS
Before HBOT
After HBOT
Case Study #3 – Spider Bite
Dog with a spider bite on his tongue
- Tongue quickly became necrotic and removed
- Lymph nodes became swollen with cellulitis and “blew”
- Approximately 20 HBOT over 4 months
- Surgical debridement mentioned, but not preformed
- Other treatments utilized were laser therapy, medical honey and salt wraps
Resource: VHMS, Case #7
Before HBOT
After HBOT
- Dog hit by a car
- 6 Days After Car Accident
- After 5 HBOT over 7 days
Resource: Veterinary Wellness Center Lexington, KY. VHMS
Before HBOT
After HBOT
Resources:
Takahashi, M., et al, Hyperbaric oxygen therapy accelerates neurologic recovery after 15 – minute complete global cerebral ischemia in dogs. Critical Care Medicine, 1992; Vol.20,No.11:1588-1593
Cuthberson, CN et al, “Hyperbaric oxygen reduces severity and improves survival in acute pancreatitis “, abstract from the 36th annual meeting of the American pancreatic association, Nov 3-4, 2005
Van Meter KW. A systemic review of the literature reporting the application of hyperbaric oxygen in the treatment of exceptional blood loss anemia: an evidence based approach. Undersea hyperbaric medicine, Vol 32, No1, 2005, 61-79
Goldman RJ, “Hyperbaric Oxygen Therapy For Wound Healing and Limb Salvage: A Systemic Review”, Physical Medicine And Rehabilitation. 2009:1:471-489
Jain KK, Textbook of Hyperbaric medicine, 5th revised edition, Hogrefe, 2009
Kendall, AC et al, “Different oxygen treatment pressures after inflammatory gene expression in human endothelial cells”, VHM 2013, Vol 40, No. 2, Pates 115-123.
HolbachKH,et al. “Improved reversibility of traumatic mid-brain syndrome with application of hyperbaric oxygen pressure” ActaNeurochir. 1974;30:247-256