News | Sep 5, 2018
Divers, pilots, and astronauts can get poisoned by too much oxygen
So can hospital patients and newborn babies, but Navy researchers may have discovered a way to keep them all safe from hyperoxia
A team of Navy researchers is advancing the safety, comfort, and survivability of their courageous colleagues using biomarkers to detect oxygen poisoning.
Pilots, divers, and astronauts traveling along the edges of the known world, often breathe high concentrations of oxygen before and after operations to reduce the risk of decompression sickness, a painful problem better known as the bends.
“We are challenged with operators working up in (outer) space, high altitude, and diving–from special ops to shallow water, using different breathing mixtures, or very deep diving and so the idea is each one of these scenarios has particular physiological risks associated with operating and surviving in those environments,” said Aaron Hall, research physiologist from the Naval Medical Research Center’s Undersea Medicine Department.
And oxygen is one of the most widely used therapeutic agents in the world. Hospitals and wound clinics use hyperbaric oxygen chambers to treat carbon monoxide poisoning, necrotizing soft tissue infections (often from burns), osteomyelitis (bone infection), radiation tissue damage, skin grafts, and sensorineural hearing loss.
In many countries, hyperbaric oxygen chambers are also used to treat newborn babies.
But getting too much oxygen is also risky.
When breathing oxygen compressed greater than atmospheric pressure, humans can get oxygen poisoning, known by medical professionals as pulmonary oxygen toxicity, which causes mild discomfort and impaired vision, then lung collapse, seizures, and death.
That’s where Hall comes in.
Along with Lt. Cmdr. William Cronin and Dr. Richard Mahon, Hall discovered how to make an oxygen poisoning alarm by monitoring six chemicals in a patient’s exhaled breath.
Chemists will know them as volatile organic compounds, specifically, benzene; 2,3,4-trimethylpentane; 1,4-dimethyl-trans cyclohexane; 2,2,4-trimethyl-hexane; 1,7,7-trimethyl-tricyclo heptane; and 4-ethyl-3-octene.
The relative concentrations of these six biomarkers can indicate pulmonary oxygen toxicity, and that’s valuable information.
“The subject’s condition can be monitored for pulmonary injuries and further injury can be prevented or reduced by limiting future exposure to high concentration oxygen,” their patent application reads. “For example, the frequency or duration of exposure to high concentration oxygen can be restricted, and the concentration of the oxygen exposed to can be reduced, thus preventing or reducing (pulmonary oxygen toxicity).”
The researchers used a gas chromatograph to analyze breath samples collected in short straws called thermal desorption tubes.
Now, using breath samples from two ongoing dive studies, one at the Naval Submarine Research Lab in Connecticut and the other at the Navy Experimental Dive Unit in Florida, the researchers are developing a predictive algorithm that will sound the alarm in advance of adverse symptoms.
With a patent application filed, TechLink, the Department of Defense’s national partnership intermediary for technology transfer, is beginning to market the Navy technology to businesses.
Last week, Quinton King, senior technology manager at TechLink, reviewed the patent for commercial applications and immediately identified hospitals that use hyperbaric therapies as a potential customer for the technology.
“The Navy research, which clearly supports the operational capabilities of our warfighters, could also be leveraged by medical device companies interested in developing new products and services for hospitals that use oxygen therapies,” King said.