Squeezing and Cleaning
The intricate rules of Shabbos are complicated to begin with, and that is certainly compounded when factoring in medical practice and medical halacha.
It is well clear, that it is forbidden to squeeze absorbed liquid out of a natural material on Shabbos, referred to by Chazal, as Sechita. However, what is not so clear, is to what extent that prohibition goes, what the overarching issur (Av Melacha) is, and some of the potential “loopholes” to permit Sechita.
The Mishna (Shabbos 143A) rules that a sponge that has a handle can be used on Shabbos, while a sponge without a handle may not be used. The issue at hand is Sechita, but the Rishonim disagree what having a handle accomplishes. According to Rashi and the Rambam, a handle will ensure that the person does not squeeze the liquid out of the sponge. The Raavad explains that a handle changes the Halachic status of the sponge from a cloth to a kli which is permitted to squeeze.
When it comes to alcohol wipes, the Tzitz Eliezer permits one to wet a part of a large cotton ball with alcohol and wipe down a wound. By ensuring that the part that one holds remains dry, one avoids any issues of Psik Reisha. Because the liquid is being discarded, this does not constitute Sechita (as a subcategory of Dash, where one wishes to use the liquid). The Tzitz Eliezer also notes that one should only rub lightly to avoid issues of Psik Reisha. However, R’ Shlomo Zalman (as brought in Shmiras Shabbos Kihilchosa) forbade using a wet cotton ball, but rather suggested applying the alcohol to the site of the wound, and using the cotton to absorb the liquid. In this manner, the cotton functions as a napkin, not a sponge, and one would avoid concerns of Sechita.
(There are other factors regarding ripping the cotton, or using synthetic wipes that I didn’t mention here, but should be considered when discussing this question with a Rabbi.)
Adapted from medicalhalacha.org