FREEZING DYNAMICS 10% CALCIUM CHLORIDE SOLUTION WITH LIQUID NITROGEN IN VITRO

Abstract

Relevance. Cryosurgical method is method of ultra-low temperatures local application for complete destruction of the pathological focus.
 Nowadays, question of cryosurgery radicality remains unsolve, because of inability to achieve lethal for tumor cells temperatures in depth from cryoapplicator.That`s why, attempts of cryodestruction improving are still keep going by developing methods of ultra-low temperatures cytodestructive effect potentiation, particulary, by their combination with chemical agents.
 Objective of the study was to determine the peculiarities of changes in temperature indices 10 % CaCl2 solution freezing in comparison with 0,9 % sodium chloride solution (0,9 % NaCl) in vitro.
 Materials and methods. Dynamic of low-temperatures changes were measured at control depths of 3, 8, 13, and 18 mm in 10% СаСl2 and 0.9% NaCl solutions by a four-channel measuring thermocouple complex KIIT-4. Cryo-tool of the original design was used for freezing. Cryoagent - liquid nitrogen (temperature -1800C). The temperature indices were detected during 10-minute exposure to liquid nitrogen.
 Results. During cryogenic exposure for 10 minutes at a distance of 13 and 18 mm from the cryoprobe, the mean temperatures in 10 % CaCl2 were significantly lower than 0,9 % NaCl (p <0,05). At control depths from 5th and 10th minute of exposure in 10 % CaCl2 the temperatures were significantly lower than 0,9 % NaCl (p <0,001).
 Conclusion. Consequently, 10 % CaCl2 can potentiate in vitro freezing processes and can be used to further improvemnt cryosurgery efficiency in vivo.