Like many arthropods, ticks breathe air through tiny openings along their body called "spiracles." Ticks are famous for surviving periods underwater because they have a reduced need for oxygen compared to other creatures. A tick breathes between one and 15 times an hour.
The reason solutions such as alcohol and nail polish work in removing ticks is because they are irritants, not because the tick becomes suffocated. Despite their effectiveness, it is not recommended to use these products in the removal of ticks due to the chance that the arthropod regurgitates its saliva and gut contents into the bloodstream of the host. This can increase the risk of disease.