Bad day low blood pressure and ventilator

Last day was a really bad day according to plan Mom was supposed to do tracheotomy but when they removed her from ventilator machin and using manual breathing device I don’t know the name. Luckily they didn’t do operation and said Bcaz she has pacemaker heart specialist should give its opinion when they brought her back to the icu her blood pressure was dramatically dropped it was 6 on 4 with lots of cold sweat we were so lucky that she didn’t have another cardiac arrest so whenever they take her out for ct scan she get this problem I blive it’s Bcaz of seperating her from ventilator machine does any one else experienced the same thing ?