Persufflation (PSF) is an emerging technique in cryonics that uses frozen gas to improve organ preservation.
When organs are donated for transplant, the most common preservation technique is to freeze them. Freezing organs though has a series of significant challenges due to ice crystals forming during the freezing process which can lead to cellular and tissue damage. To solve for this, a process called vitrification, in which low-toxicity antifreeze is injected into tissue, was discovered that allowed for the cryopreservation of organs without crystallization.
Although vitrification is highly successful, the high levels of antifreeze can be toxic and the process has some difficulties in complex organs such as hearts and kidneys.
With persufflation, gas is pumped into the organ before freezing, thereby stopping cracks from occurring while also lowering the concentration of toxic chemicals.
Although persufflation can be done with multiple gases, recent focus has been on the use of helium.