How does HBOT work?

Equine Hyperbaric Oxygen Therapy has enabled the treatment of multiple conditions not previously possible. 

How does HBOT work?

The air we breathe contains about 21% oxygen, with the remainder made up of nitrogen and tiny amounts of other gases. Red blood cells take up oxygen from the lungs, carrying it in dissolved form to all parts of the body. Even breathing pure oxygen at normal atmospheric pressure increases it only slightly.

However, putting a horse in a hyperbaric chamber and increasing the atmospheric pressure to much greater than normal is very effective in enhancing the oxygen-carrying ability of the blood and other fluids in the body to about 15-20 times more because oxygen is forced into the plasma in addition to being carried by the red blood cells.

Hyperbaric oxygen therapy, or HBOT, refers to a treatment in which a patient is placed in a sealed chamber and exposed to oxygen at several times normal atmospheric pressure. Oxygen is forced into the blood and other body fluids (lymph, cerebrospinal fluid, bone marrow), destroying bacteria and helping  heal to injuries faster than ever before. 

How is this technology available?
Hyperbaric chambers designed to treat horses are large, heavy, and complex to produce. The design is constantly being updated, and the newest models resemble circular stalls with enough room for a horse to move around and even lie down during treatment.

Physiologic mechanisms of HBOT & few indications explained

Hyperoxygenation

·       Decrease gas bubble size

·       Vasoconstriction

·       Angiogenesis

·       Fibroblast proliferation / Collagen Synthesis

·       Leukocyte oxidative killing

·       Reduces intravascular leukocyte adherence

·       Reduces lipid peroxidation

·       Toxin inhibition

·       Antibiotic synergy

·       Own stem cell multiplication

·       Decreased oxidative injury to cells

·       Reduced inflammation.

·       Immune-stimulating effects .

HBOT aids healing in the following ways:

·       Increasing oxygen to the body stimulates growth of new blood vessels in bone or soft tissue, thus allowing more oxygen-rich blood to reach the affected area after treatment.

·     Swelling and inflammation are decreased, allowing blood (and therefore oxygen) to flow more freely to the area.

·         High oxygen levels increase the ability of the white blood cells to kill bacteria in infected tissues.

·        Anaerobic bacteria are killed directly by the high level of oxygen reaching infected tissues, even if normal circulation has been affected.

Much of the basic research showing these effects has been conducted in animal models of human disease, and veterinary professionals are now able to use this information for equine patients.

What types of injuries and ailments can be treated?

Breeding: HBOT helps the uterus return to normal size and shape following foaling, and dummy foals improve with increased blood flow to the brain. The therapy has also been reported to increase libido in aging stallions.

Anemia or blood loss: For horses that are anemic and those that have lost a large volume of blood because of injury or surgery, HBOT allows the remaining blood to carry a larger amount of oxygen, sustaining body functions while more blood is being produced.

Bone infection: HBOT increases the oxygen concentration in all body tissues including bone and bone marrow. Bone infections that have not responded to traditional antibiotic therapy often clear up after treatment in the hyperbaric chamber. Joint infections in foals also respond well to this therapy.

Wounds in skin and muscle tissue: Improved oxygen delivery and stimulation of capillary formation assist in healing, especially in skin grafts, amputations, ulcerated wounds, and injuries where tissues have been crushed and circulation has been destroyed or impaired.

Laminitis: By enhancing oxygen delivery and minimizing inflammation and swelling, HBOT can dramatically minimize the destruction of tissue structures within the hoof.

Post-surgical equine patients: Horses recovering from colic surgery and other procedures benefit from HBOT to oxygenate damaged tissues, restore blood flow, and reduce swelling.

Connective tissue injuries: Torn ligament and bowed tendons heal more quickly when HBOT is included in treatment.

The goal is to use HBOT to shorten the recovery time for injuries and illnesses. The final results desired include improved survival rates for serious conditions, faster healing, less time spent in the hospital, and a healthier horse overall.

Equine clinical indications by HBOT

Commonly Treated Conditions explained:

Equine HBOT is one of the most powerful tools available as an adjunctive form of therapy, and in some cases it works well as the primary therapy in horses.

Colic and laminitis are the number one and two killers, respectively, of horses, and oxygen therapy (in conjunction with other therapies) can be very useful in treating both

• Colic: 

Equine HBOT helps restore blood flow to tissues after colic surgery. It also reduces obstructive swelling in the intestinal tissue and improves oxygenation of the resection (after abdominal surgery to correct colon torsion, small intestine strangulation, etc.) It’s been found that many colic cases respond much better to surgery when treated with HBOT before and after surgery.

• Laminitis & Navicular Syndrome: 

Equine HBOT can arrest laminitis in the early stages. If you can treat the horse before the structures in the foot collapse (before there is crushing of the blood vessels), it is very effective.

• Infections:

Equine HBOT increases blood flow to the infection site, which increases the amount of antibiotic delivery. The extra oxygen also increases the effectiveness of the antibiotic, magnifying the way it works against bacteria. High-dose oxygen tends to potentiate the effect of some antibiotics, such as sulfamethoxazole (SMZ). You are also getting 15 times the amount of oxygen to a tissue that was lacking oxygen due to infection of poor circulation. Oxygen also stimulates faster cell turnover and thus faster healing.

Certain antibiotics such as gentocin and amikacin don’t work well in low-oxygen environments. Oxygen therapy enhances their function and gives a whole combination of benefits. HBOT is an adjunctive therapy; you still use antibiotics and anti-inflammatory drugs and other treatments. It’s a component process in which everything is working together. 

* Oxygen acts to kill bacteria. 

Most bacteria causing serious infection are anaerobic—working best in an environment without oxygen. At pressure, with oxygen at a higher level, it is also detrimental to aerobic bacteria. Extra oxygen also helps white blood cells function better to kill the organisms.

• Abscesses:

Internal abscesses (such as in the lungs or the abdomen) are sometimes not diagnosed early. By the time they are diagnosed, there is a thick-walled capsule of connective tissue around them that keeps antibiotics from reaching the site. This results in prolonged antibiotic treatment (often with no resolution of the abscess) at high cost to the owner, and potentially fatal consequences for the horse. HBOT helps the antibiotic get to the site and enhances its ability to fight the infection.

• Septicemia and Joint Ill in Foals:

 
Major clinics have evaluated Equine HBOT for treating foals with septic joints. In 2002, all the foals which came into the clinic with septic joints went through a standard protocol using systemic antibiotics, lavage to flush the joints with antibiotics, etc. After 30 to 90 days of treatments, they took the foals which were hopeless (which would ordinarily be euthanized) and moved them to a test group. They continued to use their standard treatments, but combined them with HBOT. They had a 60% recovery rate in foals which were going to be put down.

• Soft Tissue Injuries: 

Many injuries result in inflammation and swelling. Studies have shown that soft tissue injuries treated with Equine HBOT recover in half the time. New blood vessels form more quickly, improving blood supply to injured areas, and there is swift reduction in edema (swelling). Since oxygen is normally carried by red blood cells, any tissues with a compromised blood supply suffer from poor healing. But with HBOT, oxygen is forced into all body fluids and delivered to areas with restricted circulation. 

* Injured tendons and ligaments respond well to treatment:

 
Equine HBOT can be useful in dealing with bowed tendons, surgical repair of tendon or ligament injuries, etc. Surgical traumas (incisions) also heal faster with HBOT, as do large surface wounds and pressure sores. It decreases tissue swelling and helpssalvage damaged tissues in traumatic injury. In chronic wounds, it assists growth of new skin and stimulates collagen production.

• Reproductive Problems:

 
A prominent DVM wrote an article three years ago and described how he’d treated some older stallions for laminitis and noticed an increase in fertility. After reading that, Winstar (the first thoroughbred farm in Kentucky to have an HBOT chamber) treated their stallion

A stallion’s covers in the breeding shed had declined, but after HBOT treatments his libido increased (along with his sperm count), and the morphology (cell structure) of his semen was much improved.

HBOT has also worked well for mares they hadn’t been able to get in foal. 
Four out of five mares were treated one year, that had been bred on multiple covers. They were put in the HBOT chamber and got into foal the next time they cycled. And the integrity of the uterine lining was probably enhanced.
A rehab clinic in the US has also treated mares that were unable to concieve. One mare went to the breeding shed 16 times in two years without becoming pregnant. After three treatments in the HBOT chamber, she was bred, and had a live, healthy foal.

• Dummy Foals and Other Neurological Problems: 

Used on dummy foals, it reduces edema. The oxygen in a pressure chamber has the ability to penetrate the cerebrospinal fluid. Head and spinal trauma often create neurological damage, thought to result from swelling of these tissues within a confined space, loss of blood and oxygen supply, and the sequential effects of these factors on nervous tissue. HBOT reduces the swelling and increases the blood supply.

Hyperbaric oxygen therapy is also potentially beneficial for athletic and non-athletic injuries or ailments, including:

·       Improved rate and degree of recovery in equine athletes

·       Improved well-being and demeanor

·       Desmitis (ligament disease)

·       Tendonitis (bowed or diseased tendons)

·       Fractures

·       Exercise-induced pulmonary hemorrhaging (Bleeders)

·       Acute laminitis (Founder)

·       Reperfusion diseases (severe muscle damage, crush injuries)

·       Colic (intestinal obstruction, colonic torsions, volvulus, etc.)

·       Enteritis and endotoxemia

·       Ileus (loss of intestinal motility)

·       Infertility (mare and stallion)

·       Rhodococcus pneumonia in foals

·       Lyme disease

·       Osteomyelitis (bone infection)

·       Compromised wounds

·       Myositis (tying up)

·       Septic arthritis (joint infections)

·       Neurologic disease

·       Severe necrosis (e.g. snake and spider bites, toxic substances, etc.)

·       Neonatal maladjustment syndrome

·       Lung and abdominal abscesses

·       Gastric ulcer healing. Prevention of ischemia reperfusion injury post colon torsion

·       Any intestinal ischemic injury

·                            Exercise-induced pulmonary hemorrhage.

·      Post-race or post performance recovery