Add commas to make sentence complete.
She is status post cholecystectomy, appendectomy, and bilateral hip prostheses.
Abdomen was soft gassy and nontender.
The commas in your first sentence are correctly placed. Now you correct the second sentence and post your work, and I'll check it for you.
https://owl.purdue.edu/owl/general_writing/punctuation/commas/extended_rules_for_commas.html
To make the sentence complete, you need to add commas in the appropriate places. Here's the corrected sentence:
She is status post cholecystectomy, appendectomy, and bilateral hip prostheses.
Abdomen was soft, gassy, and nontender.