Ripped from the clutches of snake oil medicine and arguably one of the most exciting and versatile healing and anti-aging therapies of the modern day, Hyperbaric Oxygen Therapy (HBOT) is extremely safe, drug-free, and relaxing all at the same time. But you’ve probably never heard of it. Or if you have, it was probably as a treatment for decompression illness, carbon monoxide poisoning, diabetic foot ulcers, or possibly necrotizing fasciitis. While it is true that HBOT is amazingly effective for all three of these conditions (and the other 11 that are currently FDA-approved to treat), there is so much more it can do.
In the 17th century, a British clergyman named Henshaw made an airtight chamber attached to an organ bellow. The organ bellow could be rigged to either pump more air into the chamber (i.e., compressing more air into a fixed space) or suck air out. When air was pumped in, this became known as a hyperbaric environment. A hypobaric environment was the opposite: a chamber with air sucked out of it. In the 18th and 19th centuries, hyperbaric air was thought to treat acute conditions while hypobaric air was ideal for chronic conditions such as tuberculosis. No real research backed up any of these claims, however.
The modern age of hyperbaric medicine began with the treatment of decompression illness, a terrible condition that to this day still kills, paralyzes, or injures (many times severely) those who suffer from it. Before it was known as decompression illness, however, it was known as “the bends” and the number of people affected was staggering after the boom of suspension bridge building during the middle to the end of the 19th century. Bridge workers were sunk deep beneath the water surface in pressurized chambers called caissons. The caissons were pressurized to keep water out as the workers sealed in them dug deep into the riverbed floor to anchor the bridge pile-ons. If these workers were transported in elevator shafts back up to the surface too quickly, the “bends” occurred to devastating effect.
What was pivotal, however, was the realization that if these workers went back down into the caissons, their symptoms went away. This occurred during the building of the Brooklyn Bridge in the late 19th century. The patients with mild, moderate, or even severe injuries who “toughed it out” and went back into the caisson the next day had some or all of their symptoms resolved.
The explanation, also discovered at the end of the 19th century, was a simple one: There was 21% oxygen and about 78% nitrogen in the air at sea level. When caisson workers were under water, all that water above them was exerting pressure on the air they were breathing. Although the same ratios of gases remained (Dalton’s Law), the amount of nitrogen and oxygen dissolved into the bloodstream increased dramatically (Henry's Law). Henry's law is important in hyperbaric medicine and worth defining: the more pressure exerted on a gas, the more of that gas changes into the liquid state. This liquid state in the human body turns out to be in the plasma of the blood. So in reverse, decreasing pressure (decompression) changed liquid nitrogen and oxygen back into their gaseous states.
The problem of “the bends “ was one of depressurizing too quickly, causing nitrogen to bubble out of blood circulation back to the gaseous form in such large quantities that it could potentially overwhelm circulatory flow. Nitrogen gas literally blocked blood flow to tissues, causing micro and macrovascular ischemia. The key to treatment was to get those gas bubbles back into liquid form as soon as possible by re-compressing the air pressure to the condition that it had been for the caisson worker (and later deepsea divers) before they surfaced.
The results were nothing short of miraculous but it was no miracle.
This was exactly what a hyperbaric chamber was capable of doing, and soon chambers were made available at bridge construction sites, and later on at dive meccas all over the world. Paralyzed, seizing, and severely injured patients could walk out of the chamber symptom-free a few hours later. The results were nothing short of miraculous but it was no miracle. Hyperbaric chambers re-dissolved the nitrogen bubbles and restored blood flow.
In the late 1960’s, the Undersea and Hyperbaric Medicine Association (UHMS) was born. Then a second indication for HBOT also came to the forefront: Carbon Monoxide poisoning. The results, just like decompression illness, were dramatic: intubated and severely injured patients underwent complete reversal of their symptoms a few hours later. My first experience with hyperbaric therapy was witnessing this first hand. The question I asked myself was: if oxygen could be so healing for these patients, why wasn’t it being used for other patients who were starving for it?
Fast forward to 2016, and now there are a total of 14 FDA-approved indications in the United States. In many European and Asian countries, that number is closer to 60. What all of these indications have in common is if there is ongoing inflammation and a wound or injury that needs help healing.
There are three types of hyperbaric chambers: Hard-shelled multiplace chambers that can treat many patients at the same time, hard-shelled monoplace chambers that treat one person at a time, and soft-bag chambers. Multiplace and monoplace chambers work by increasing atmospheric pressure while having the patient breathe 100% oxygen. From Henry's Law, as mentioned above, we now know that doing this can lead to a dramatic increase in the amount of oxygen dissolved into the blood circulation. This effect is not felt at the red blood cell (RBC) level, however, because 96% to 100% of hemoglobin sites on the RBC are saturated when they travel through lung capillaries in a normal individual. Instead, oxygen is driven into the plasma of the blood to levels that can exceed 12x those at sea level (or greater than 1200%). Normal blood oxygen levels at the tissue level range from 45 to 55mmHg. During HBOT treatment, the arterial O2 tension typically exceeds 2000 mmHg, and levels of 200–400 mmHg occur in the body tissues. Soft-bag chambers, it should be noted, typically have air compression that does not reach the same pressure depths as the hard-shelled chambers. Despite this difference, in my experience they may still have a therapeutic benefit although no studies using these chambers have been performed thus far except in acute mountain sickness (it is FDA approved for this).
No matter the chamber, the therapeutic effect of HBOT comes from the supraphysiologic plasma oxygen concentration. This leads to a cascade of changes that can affect the body in at least one of five very specific ways: by acutely reversing hypoxia, decreasing inflammation, optimizing all stages of wound healing, revitalizing mitochondria, and fighting infection.
Acute tissue ischemia is the etiology of the number 1 and 2 killers globally: Ischemic Heart Disease and Stroke. It is also the etiology of acute compartment syndrome, acute traumatic ischemia, crush injuries, decompression illness, and carbon monoxide poisoning—all of which are currently FDA-approved HBOT indications.
HBOT saves tissue, whether it be heart muscle during an MI or scar mitigation after an elective plastic surgery.
An acute exposure to HBOT increases blood oxygen dramatically—by over 1200% as detailed above—allowing more cells in an area of ischemia to survive secondary to higher oxygen concentrations diffused into the tissue, thus maintaining ATP production in more at-risk cells. HBOT saves tissue, whether it be heart muscle during an MI or scar mitigation after an elective plastic surgery. A recent randomized, placebo-controlled study showed a 50% decrease in mortality when patients with a severe acute traumatic brain injury received just three HBOT treatments over three successive days. Studies are under way to look at HBOT during an acute CVA as well.
A recently published study from China also showed that acute hyper-oxygenating may lead to cognitive performance enhancements as well. College students were treated with five HBOT exposures over a five-day period. Improvements in their spatial working memory were seen and confirmed on functional MRI scanning.
HBOT heals wounds no matter where they are in the body by accelerating all stages of wound healing. It works by modulating the transcription of over 8,000 genes; upregulating genes responsible for growth and repair, and downregulating genes responsible for inflammation and program cell death. The end results can include: improving leukocyte adhesion, neutrophil function and macrophage killing, vasoconstricting blood vessels to mitigate edema, decreasing inflammation by downregulating the release of IL1, IL 6, and TNF alpha, inhibiting apoptotic pathways, re-populating areas of injury with new stem cells released from the bone marrow that migrate to areas of injury, and stimulating angiogenesis via VEGF and Hypoxic Inducible Factor (HIF) dependent pathways. HBOT also stimulates chondrocytes to produce new collagen, osteoblasts to lay down more bone, and fibroblasts to make more connective tissue.
The key is its ability to reverse hypoxia and decrease inflammation, which are often the core etiology of any wound.
HBOT can heal wounds large and small, accidental, age-related or iatrogenic (such as from surgery). The key is its ability to reverse hypoxia and decrease inflammation, which are often the core etiology of any wound. To this end, HBOT is FDA approved to treat diabetic foot ulcers, radiation injury from cancer treatment, thermal burns, decompression illness, and carbon monoxide poisoning.
Although the findings are still under investigation, there is evidence that HBOT may also be an effective treatment for Inflammatory Bowel Disease (Crohn’s and Ulcerative Colitis), Reflex Sympathetic Dystrophy, patients with post-CVA, chronic TBI, and used as either the sole treatment or synergistically with additional treatment modalities (see below). Emerging evidence is also starting to show a possible roll in Alzheimer’s and Parkinson’s disease.
HBOT increases ATP formation by providing supraphysiologic amounts of oxygen to mitochondria necessary for cellular respiration. A recent study involving the hippocampi of rats reported that HBOT increased mitochondrial biogenesis and autophagy through, in part, an increased production of reactive oxygen species (ROS). Through this process, new healthy mitochondria were produced, and old dysfunctional mitochondria were destroyed. This study also found increased activation of mitochondrial DNA transcription and replication with HBOT.
HBOT has been shown to also upregulate the production of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, catalase and other enzymes. This increase in antioxidant levels protects against damage that potentially could result from excess ROS, which can be deleterious.
Mitochondrial degeneration and dysfunction are thought to be two of the primary etiologies of aging and possibly of cancer. With regards to cancer, there have been several recent studies of mice combining the ketogenic diet with HBOT that demonstrated a significant decrease in metastatic cancer burden.
It should be noted that there is also no indication that HBOT has a pro-growth effect on cancer. The last review in 2012 indicated HBOT had a static effect or a potentially receding effect, the latter occurring in very hypoxic tumors such as glioblastoma multiforme.
HBOT is a bactericidal antibiotic that effectively treats anaerobic and facultative anaerobic organisms, especially when used in synergy with aminoglycosides, cephalosporins and clindamycin. It is also an effective mitigator of endotoxin release in necrotizing fascitiits caused by Clostridium Perfringens, and it is FDA-approved to treat this condition as well as chronic refractory osteomyelitis and diabetic foot ulcers, which are often superinfected.
In addition, although not approved by the FDA, there is evidence that HBOT may be an effective treatment for Lyme Disease, MRSA infections, Small Intestine bacterial Overgrowth (SIBO) and other maladies.
HBOT is typically done on successive days, Monday through Friday, with the weekends off, secondary to the need for elevated oxygen concentrations over time to stimulate changes to protein transcription/DNA modulation. Protocols can be as short as two treatments and as many as 120 depending on the indication.
In general, the more the acute the indication, the fewer treatments are typically needed. For example, in patients undergoing plastic surgery, three to five sessions will suffice. For long-standing infections such as diabetic foot ulcers, radiation injury or patients who are post CVA, treatment protocols are in the 30- to 60-treatment range. At most centers, more superficial pressures are used to treat patients with CNS conditions, while deeper pressures are often used for wounds outside of the CNS, including peripheral nerve injuries.
The only absolute contraindication to HBOT is an untreated pneumothorax. The most relatively common contraindications that will preclude HBOT include bullous lung disease, congestive heart failure with an EF <35%, pregnancy, COPD, restrictive lung disease, a history of uncontrolled seizures, ongoing fevers, uncontrolled hypertension and severe acute or chronic eustachian tube dysfunction.
With regard to potential side effects, the pressurization during HBOT is felt at the tympanic membrane so there is always the potential for tympanic membrane injury. Having a cold, chronic sinusitis or allergies can put a patient at higher risk for having a tympanic membrane injury. HBOT has also shown to increase the maturity rate of cataracts. All patients at risk should be screened prior to HBOT. In addition, HBOT increases insulin sensitivity, and thus diabetic patients must eat prior to going into the chamber, and their finger stick should be checked. HBOT can also increase blood pressure by about 10 points systolic and diastolic, and thus no patient is allowed into the chamber with an uncontrolled blood pressure, typically a systolic >160 and a diastolic >100.
The more severe potential side effects of HBOT are also much rarer. This includes a pneumothorax, which, when it does occur, is usually in patients with bullous lung disease or previous lung injury. Oxygen-induced seizures are also possible. These present as tonic-clonic seizures. HBOT facilities have several ways to mitigate the potential for these side effects to occur. But if they do happen, no long-term effects have been reported.
I am an integrative physician with significant experience in HBOT. To this end, I have found time and time again that HBOT protocols benefit substantially from an integrative/multidisciplinary approach. On occasion, HBOT is the only therapy needed. These examples would include HBOT for surgical recovery or HBOT for an acute traumatic brain injury. But more often than not, there are ways to optimize the HBOT treatment protocol.
In my practice, I first look at a patient's genetics and blood work (including hormone testing) to ensure that we take all measures possible to optimize both prior to HBOT. I then supplement where needed to augment genetics/lab work. A common example of this is starting methylated B12 and folate in patients with MTHFR homo or heterozygosity.
Prior to HBOT, I will also often recommend a structural, functional, and occasionally a cognitive assessment (the latter in patients with traumatic brain injuries, PTSD or chronic pain), which may include chiropractic, physical therapy, acupuncture or osteopathic consultation depending on a patient’s need. A structural assessment is vital since no lasting change is possible if there is a significant structural abnormality that is impeding recovery. In my experience, HBOT may help for a time but the results will likely be fleeting if the underlying etiology is not addressed. A common example in my practice is a patient who presents an acutely herniated lumbar disc. HBOT will help with pain and inflammation but chiropractic or osteopathic manipulation is essential for lasting improvements.
"...I have also found that diet is a very important."
Adjunctive technologies or therapies are also an important part of optimizing HBOT. Some of these include neurofeedback, low-level light therapy, VASPER compression, vision retraining, traction devices, prolozone, PRP (even intranasally), and many others. These technologies work synergistically with HBOT to optimize results.
Finally, I have also found that diet is very important. In my experience most patients improve with this approach. But patients improve the fastest when they follow a diet that is low in carbohydrates, low in all forms of sugar but especially in processed sugar, moderate in clean protein, and high in good fats that approach ratios which allow cyclical (or at least occasional) ketosis. Ketosis, when the body is burning fat instead of glucose as an energy source, is a promising dietary strategy. Recent research has shown the power of ketosis for enhancing cognitive as well as athletic performance. There are even some early indications that ketosis can improve blood flow and may have an anti-cancer effect as well. The Bulletproof Diet, the Modified Atkins diet, and, of course, the ketogenic diet are examples of diets that allow you to be in cyclical ketosis or ketosis all the time.
One additional point on fat: It is essential for the brain and nerves to heal. The brain is made of about 60% fat, found most prominently in myelin sheaths, so a diet tailored for healing the brain requires high amounts of fat (good fats such as those from avocados, coconut oil, grass fed meats and even grass-fed butter).
The power of integrative health is akin to “strength in numbers”: using synergistic and complementary approaches to optimize results. I encourage people to think of HBOT as an advanced wound-healing accelerator and a powerful anti-inflammatory. If there is a wound or inflammation, HBOT should seriously be considered as a primary or adjunctive therapy to augment recovery.
*Note: This article was updated. The original version referred to Charles' Law, when in fact, the correct reference is Henry's Law.