The use of cryogens or cryotherapy, curettage, laser therapy, electrocautery or surgical excision all assist in treating keratosis – the first being the most popular. Studies reported that it is the second-most common procedure next to surgical procedures such as skin excision and it can easily be performed in the doctor’s office.
In cryotherapy, extreme cold is applied to a specific area of the body to freeze off unwanted skin lesions including warts and keratosis, both actinic and seborrheic. However, this treatment process is recommended only for superficial, flattened or slightly palpable skin lesions for it has not always been successful in removing thicker lesions.
So how does cryotherapy work? The arteries and veins, generally known as blood vessels, located at the injury site such as the lesions’ site, are compressed by cryotherapy. The site then receives lessened blood flow due to this process, commonly referred to health professionals as vasoconstriction. Because of lesser blood supply, the cells cannot receive the nutrients that they normally get from the blood including oxygen. Eventually, the adverse effect is cell death or necrosis.
Liquid nitrogen, carbon dioxide snow and DMEP or dimethyl ether and propane, are some of the chemicals utilized to yield extremely cold temperatures and which are called cryogens. But amongst the three, liquid nitrogen is the most commonly exercised cryogen by physicians primarily because of its low boiling point, making it a highly efficient cryogen.
At the beginning of the treatment, the physician directly applies the liquid nitrogen onto the skin using a cotton-tipped applicator, a cryospray or a cryoprobe. Immediately after this, the liquid nitrogen evaporates within a minute once heat transfer from the skin to the cryogen takes place. Thawing of the skin lesions then follows this short freezing time. This is the time that the actual cell injury starts to occur – when the intracellular contents begin to leak out. Cell inflammation, the final step of the process, finally sets in making the skin reddish, swell, painful and warm.
Cryotherapy, in general, is safe when administered properly. But like many other procedures, complications can and will arise. To illustrate, prolonged freezing by the liquid nitrogen results to hypopigmentation or change in the skin color, specifically a lighter color.
Even though the Resource Conservation and Recovery Act does not regard liquid nitrogen hazardous, it still poses deleterious effects on humans who come in direct contact with it for this will produce rapid freezing of the tissues or even tissue death. There are two types of exposure to liquid nitrogen: inhalation and direct contact. Inhalation effects are not that toxic unless a significant amount of liquid nitrogen is spilled, thereby reducing oxygen levels prompting the need for respirators. Workers involved in its transportation must therefore adhere strictly to transportation safety protocols.
Eye contact with liquid nitrogen can occur during its transfer to smaller containers. Or there can be accidental direct contact with the skin.
Therefore, for both the medical practitioners and the laypersons alike: practice utmost safety when handling liquid nitrogen. If your work involves liquid nitrogen, make sure you have the entire protective suit covering your face and your body. When leaks are inevitable, remove anyone unprotected from possible exposure. And if liquid nitrogen ever comes in contact with the skin, and not during a cryotherapy, the frozen skin should be soaked in water that is 41-46 degrees Celsius in temperature before immediately consulting a doctor.