“They Shoot Horses Don’t They?”

Fairfield T. Bain, DVM

Nathan M. Slovis, DVM

Hagyard-Davidson-McGee, PLLC

4250 Iron Works Pike

Lexington, Kentucky 40511

As for the opening question, the answer is “yes,” but the veterinary profession is making strides to salvage many of our equine patients that in the past would be euthanized for severe injury or chronic diseases.  Here in central Kentucky, much of our work revolves around the Thoroughbred breeding industry.  Many of our patients are critically ill equine neonates or their mothers who have experienced some illness during or after their pregnancy.  Three years ago, we were introduced to the application of hyperbaric oxygen therapy as a tool for treatment of birth asphyxia.  That is the most common reason for a neonatal foal to be admitted to our Neonatal Intensive Care Unit.  That first season, we learned a lot about the ability of hyperbaric oxygen therapy (HBOT) to aid in the recovery of a foal from this potentially devastating problem.  Our patients are much more developed at birth than a human neonate so cerebral palsy is not such a problem for us.  Even with the advanced state of brain development in the foal, birth asphyxia is one of the more costly neonatal illnesses and can result in seizures or coma as well as dysfunction of a multitude of other organ systems (especially the kidney and gastrointestinal tract).  Early identification of foals at-risk for this disorder can result in an improved outcome and shorter hospital stay.  Our first experience with HBOT was in treating comatose neonates with severe birth asphyxia.  We were impressed at the response and were able to discharge several seriously ill foals with no long-lasting consequences. 

Another common and potentially devastating illness of young foals is bone and joint infection secondary to bacterial septicemia.  Many times, this problem is in an advanced state by the time it is recognized and there is significant bone destruction seen on the radiographs of the affected joint.  In years past, many affected foals would be lost due to destruction of the growth plate or pathologic fracture.  We began a clinical trial using HBOT for these foals and were able to salvage many foals with significant bone destruction.  This has now become one of our most clinical problem treated in our hyperbaric chamber. 

Wound care is a common problem for horses.  Following the experience with human patients, we have begun to treat traumatic injuries as well as chronic wounds in the hyperbaric chamber in an effort to salvage injured tissue as well as to enhance wound healing.

Hyperbaric Oxygen Therapy: A powerful tool in addressing military and terrorist violence

by Thomas M. Fox M.S., M.AS. CHT

On  September 11, 2001, our world changed as the unimaginable happened. This sentence has been repeated over and over in the press and media. The unimaginable in this case was the simultaneous, coordinated hijacking of four commercial airliners, which were directed to four strategic targets, symbols of America, selected for their recognition and impact value.

Could this be prevented from happening again? That is the question being asked repeatedly as we watch the 9-11 hearings. The answer is most likely not. Terrorists traditionally kill people and destroy property, usually soft targets, to get what they want. Although many of the same injuries are seen in combat, terrorist acts differ from military action as a rule in that they are more likely to generate concentrated mass trauma.  Incredible as the coordinated assault of 9-11-01 was, it was the first of its type in scope, and coordinated its assault in order to use the media to perpetuate its impact. It further sets the bar higher as new terrorist attempt to plan the new unimaginable.

In looking at terrorist acts and violence during a fifteen month period in Israel, (2.4%) of the total hospital admissions were the result of terrorists activities. The following observations were made; Injury mechanism consisted mainly of explosions (n = 269, 48%) and gunshot injuries (n = 266, 47%). One third of the population experienced severe trauma (Injury Severity Score > or = 16). One hundred-forty-two patients (26%) needed to be admitted to the intensive-care unit. Inpatient mortality was 6% (n = 35). Fifty-five percent of the injuries (n = 306) included open wounds and 31% (n = 172) involved internal injuries; 39% (n = 221) sustained fractures. Half of the patients had a procedure in the operating room (n = 298). Duration of hospitalization was longer than 2 weeks for nearly 20% of the population ⁽¹⁾

As we plan contingency responses to address this new threat, we must evaluate all the assets available to our medical communities to respond to ruthless and sophisticated acts of violence. One important and often overlooked asset is a multi-place hyperbaric oxygen chamber that may simultaneously treat between 2-15 people. In the simultaneous treatment of this number of patients, the hyperbaric chamber can be a force multiplier simultaneously providing oxygen to tissues in critical need, making the patient’s immune system function more effectively, neutralizing chemicals, stopping the production of bio-toxins and antagonizing the effects of reperfusion injury.

Historically, in terrorist acts, the concentrated number of casualties and injured increase the demand for and overwhelm the capabilities of the acute care medical system. In acts of terror and military action, the injuries characteristically fall into several categories which respond well to treatment with hyperbaric oxygen; crush injuries, compartment syndrome, burns, gas gangrene, limb salvage, carbon monoxide poisoning, smoke inhalation and cyanide poisoning, chemical poisoning, acoustic trauma, difficult wounds with compromised tissue and mild traumatic brain injury caused by flying or collapsing debris, falls or even blast waves due pressure changes associated with an explosion.

Hyperbaric oxygen has been used to reduce a complication rate of 50% in crush injuries by approximately one third. In a randomized control study of crush injuries by Bouachour et al primary healing improved by 35% and the need for additional surgeries decreased by 27% in those cases treated with hyperbaric oxygen⁽²⁾.  Additionally, complications of fractures were reduced 49% and amputation rates lowered by 50%.^{(3 & 4)}

Hyperbaric oxygen is also useful in lowering the costs by 75% when used in the treatment of compartment syndromes in the Impending stage to prevent progression as compared to using HBOT in the Established stage to managed complications.⁽⁵⁾  The early use of Hyperbaric Oxygen Therapy (HBOT) in the coordinated treatment of compartment syndrome brings about the desired outcome with tremendous cost savings or more appropriately cost avoidance.

In the case of burns, hyperbaric oxygen therapy is important as an adjunctive therapy that has demonstrated to provide a significant reductions in hospital stay in patients with greater 39% TBSA⁽⁶⁾. HBOT when fully integrated into the therapeutic approach to  patients with burns 40-80% TBSA was able to reduce the need for surgeries including grafting. The end result when compared to those patients not treated with HBOT was to show an average savings of over $107,000.00 (36%) per case.⁽⁷⁾ 

Gas gangrene is a general toxi-infection, which is mostly the result of a contamination of the muscles from traumatic or post-operative origin. Muscular necrosis expands very quickly, causes mutilations, hits several organs and leads to shock. In World War I, 10-12% of all casualties were attributed to gas gangrene. Improvements in the chain of evacuation and antiseptic techniques saw this figure decrease to less than 2 cases per 1,000 in Vietnam. The mortality associated clostridial myonecrosis before 1960 was 70% and since that time is 40%.  In this case HBOT is adjunctive and works by stopping the production of alpha-toxin, a lecithinase. A successfully integrated hyperbaric oxygen service with the surgical service minimizes tissue loss, preserves function and reduces the time required for rehabilitation.⁽⁸⁾

There are no less than seven articles available through National Library of medicine that speak to the effectiveness hyperbaric oxygen therapy in treating the obliterative effects of explosive mine wounds to the extremities, vascular injuries and limb salvage due to military actions. Most focus on the studies from Croatia that speak about limb salvage through vascular reconstruction. Schramek and Hashmonai in the British Journal of Surgery that hyperbaric oxygen treatment was used in 7 cases in which successful arterial repair did not reverse ischemia, and it prevented major amputations.⁽⁹⁾

In the carbon monoxide poisoning, smoke inhalation, cyanide poisoning and chemical blood agent poisoning the agent interferes with the hemoglobin’s ability to carry oxygen to the body’s tissues in this instance hyperbaric oxygen therapy delivers oxygen through supersaturating the plasma. In this way the body’s tissue oxygen requirement met until dissociation occurs or the agent is neutralized.

Demaertelaere and Van Opstal looked at the treatment of acoustic trauma occurring in military service (due to shooting, explosions, ...) They found a statistically significant amelioration of this hearing-loss when  patients were treated with hyperbaric oxygen therapy. The results as shown in the diagrams, are more convincing when we give a complete hearing-protection during the treatment and when they could start the HBOT as  soon as possible following the trauma. ⁽¹⁰⁾

One of the best applications for hyperbaric oxygen therapy is in the treatment of difficult wounds with compromised tissue. Difficult wounds are those that fail to heal by primary intention within 3-4 weeks.  The tissue in a difficult wound is compromised, infected and/or ischemic.   Radonic et al reported that popliteal vascular injuries caused by typical military mechanism during the war in Croatia present large and extensive defects of tissues and bones, are often associated with other injuries and require more extensive surgical therapy. Delays in the evacuation of the wounded contribute to the difficult conditions as well as considerable organization and transportation problems are characteristic for this war and greatly affect the success of vascular reconstruction. Hyperbaric oxygen therapy offers a safe noninvasive method of improving wound healing and decreasing edema formation in popliteal vascular injuries.

In the chaos following explosions, diagnosis of Mild Traumatic Brain Injuries (MTBI) may be missed. Timely diagnosis and treatment of long term consequences of MTBI is needed. In this case, the use of Hyperbaric Oxygen Therapy in a timely manner prevent the damage associated with micro-hemorrhages and the associated reperfussion injury and swelling. Early MTBI symptoms may appear mild, but untreated they can lead to a significant, life-long impairment, affecting an individual’s ability to function cognitively, physically, and psychologically.⁽¹¹⁾

Injuries from terrorist acts are severe and impose a burden on the healthcare system.

The value of a fully integrated multi-place hyperbaric service in addressing the conditions brought about by military and terrorists’ violence cannot be understated. The exceptional clinical outcomes seen in incorporating hyperbaric oxygen into the treatment of these conditions are truly remarkable. Hyperbaric oxygen therapy is a versatile and powerful weapon in the arsenal of medical contingency planners in addressing the terrorist threat.

Bibliography

(2)   Bouachour G, P Cronier, JP Gouello, et al. Hyperbaric oxygen therapy in the management of crush injuries: A randomized double-blind placebo controlled clinical trial. J. Trauma 1996;41: 333-339

(3)   Caudle,RJ, PJ Stern. Severe open fractures of the tibia. J Bone Jt Surg 1987;

69 A(6): 801-807.

(4)   Matos, LA, JJ Hutson, H Bonet, EA Lopez. HBO as an adjunct for limb salvage in crush injuries of the extremities. Undersea and Hyperbaric Med 1999; 20(Suppl): 60-61 (#187)

(5)   Strauss, MB. Editorial: Cost-effective issues in hyperbaric oxygen therapy: Complicated Fractures. J Hyperbaric Med 1988; 3(4): 199-205

(6)   Cianci P, H Lueders, H Lee, RL Shapiro, J Sexton, C Williams, R. Sato. Adjunctive hyperbaric oxygen therapy reduces length of hospitalization in thermal burns. J Burn Care Rehabil 1989; 10: 432-435

(7)   Cianci P, H Lueders, H Lee, RL Shapiro, J Sexton, C Williams, B Green. Adjunctive hyperbaric oxygen reduces the need for surgery in 40-80% burns. J. Hyperbaric Med 1988;3:97.

      (11) Centers for Disease Control and Prevention TBI Fact Sheet 

  Centers for Disease Control and Prevention Heads Up: Facts for Physicians          

 About Mild Traumatic Brain Injury (MTBI), 2002.

The Dream That's Not Impossible
By Captain Frank A. Manson USN Ret.


Let us dream for a moment about the promises of pressurized oxygen. Let us suppose that all our nation's children suffering from Cerebral Palsy and other types of brain damage could receive hyperbaric therapy, that the chambers were available and the technicians were available to administer to the children.

We would see the severely retarded become moderately retarded at a minimum, the moderately retarded would advance to fair and the fair would advance to normal. These are reasonable expectations.

Let us suppose the brain-damaged adults, those unable to walk, talk or recognize their families could be given hyperbaric therapy, patients such as my wife. They would once again be able to walk, enjoy jokes and television, help plant gardens and give each family member a big hug with instant recognition. The quality of life for those living in nursing homes could be improved and many could return home to their families

Let us suppose medical schools began teaching the benefits of hyperbaric therapy to their students, that physicians from all the hyperbaric nations could freely exchange information on the successes achieved through the various protocols they used in specific diseases, that Sports teams used hyperbaric therapy as routing to hasten the healing of their injured athletes, that veterinarians recognized the many uses of pressurized oxygen in helping the animals back to health.

These are not impossible dreams. I dream about them daily when I watch the progress of my wife who gets hyperbaric therapy about 4 times each week.