MICU-medical intensive care unit....and it is not a stepdown unit. patients are sicker. ratio is 1:1 or 2:1 patients to nurse. once the patients start to get better they are transferred to a MICR medical intensive care recovery (stepdown) or a medical/surgical floor where the ratio can range from 5:1 to 8:1 or more depending on the acuity of the patients. ratio is usually 4:1 for a stepdown.
SICU surgical intensive care unit. and the same would follow for a Surgical Intensive Care Recovery SICR (stepdown unit).
I work on a Cardiac Stepdown and love it. the patients are still sick, just not sick enough for the ICU, and not well enough to go home. Lots of time they need more monitoring then a floor nurse can provide due to the ratio of patients assigned & frequency of assessments. sometimes the patients get worse and you end up transferring them to the ICU, depending on which ICU they need (medical, surgical, cardiac). not every ICU is separated, some are combined.

hope it helps a bit. good luck to you in nursing career!
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