A unit of measure denoting lodging facilities provided and services rendered to one inpatient between the census-taking hour on two successive days. The day of admission but not the day of discharge or death is counted as a patient day. If both admission and discharge or death occur on the same day, the day is considered a day of admission and counts as one patient day.
N.Y. Comp. Codes R. & Regs. Tit. 10 § 441.245