Various patient monitoring systems can include a sensor configured to collect three dimensional information. The systems can identify a location of a patient support surface based on the three dimensional information. The systems can set a two dimensional planar threshold based on the patient support surface. The systems can identify a patient location above the patient support surface based on the three dimensional information and compare the patient location to the two dimensional planar threshold. Exceeding the threshold can be indicative of a high risk of a patient fall. An alert can be generated based on the threshold being exceeded. The systems can repeat the identification of the patient support surface location and the setting of the threshold to account for changes in the patient area.
