Carbon tetrafluoride reduces the severity of decompression sickness in pigs
- Ten minutes of breathing CF4 and O2 before decompression in pigs
- The number of gas bubbles in the blood and nerve damage decreased
- Mortality dropped from 30% to 8% in the experimental group
- Low diffusion of CF4 may increase the safe diving depth
Scientists from the USA conducted an experiment in which pigs were allowed to breathe a mixture of carbon tetrafluoride (CF4) and oxygen for ten minutes before diving into a hyperbaric chamber. After subsequent decompression, the animals showed a noticeable reduction in symptoms of decompression sickness – a condition caused by the formation of gas bubbles in tissues and blood due to a rapid drop in pressure.
The study showed that animals receiving training with the gas mixture had nearly half the number of microscopic bubbles in their blood compared to the control group that breathed regular air. Additionally, the degree of nervous system damage, assessed by morphological and biochemical markers, was significantly lower.
A key result was the reduction in mortality: the death rate among pigs that underwent training with CF4 decreased from 30% to 8%. The researchers attribute this effect to the low diffusion capacity of carbon tetrafluoride, which they believe slows the growth of gas bubbles in tissues during ascent to the surface.
Why this is important for diving
Decompression sickness remains one of the main threats to professional and recreational divers, especially during rapid ascents from great depths. Traditional prevention methods include gradual pressure reduction and the use of oxygen 'cleanses' after surfacing. The proposed approach – pre-vacuum preparation with a gas mixture – may become an additional tool to increase the safe diving depth.
Carbon tetrafluoride is already used in some industries as an inert gas mixture; however, its properties in the context of decompression processes have been studied only to a limited extent. The low solubility of CF4 in blood and tissues makes it a potential 'barrier' to the growth of nitrogen bubbles, which are the main cause of decompression sickness.
The authors of the study emphasize that the obtained data require further verification in humans. The transition from animal experiments to clinical trials will require an assessment of the safety of prolonged inhalation of CF4, as well as the development of practical protocols for divers.
The results of the work have been published in the journal Proceedings of the National Academy of Sciences (PNAS). Scientists plan to continue research by studying the effects of different concentrations of tetrafluoride and the duration of pre-vacuum preparation, as well as testing the effectiveness of the method in real marine immersion conditions.
If further research confirms the effectiveness and safety of this technique, it could be an important step in reducing the number of accidents related to decompression sickness and expand the boundaries of safe dives for professional divers and rescue services.
Source: N+1
