1. A method of displaying trends and variability in a physiological dataset, comprising, on a processor: obtaining the physiological dataset; applying a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset; applying a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset; outputting a real-time graph of the trend of the physiological dataset; outputting a real-time graph of the variability of the physiological dataset overlaid on the graph of the trend of the physiological dataset, wherein the graph of the variability of the physiological dataset comprises a real time visual envelope bounded on the top by a plot of the maximums identified by the variability algorithm and bounded on the bottom by a plot of the minimums identified by the variability algorithm, where said maximums and minimums are identified within each time window over which the variability is estimated; and triggering at least one of an audible or visual alarm upon a predetermined condition in the variability or trend of the physiological dataset being met whereas the predetermined condition is based on at least one of: (1) ratio between variability and trend values within a time window, (2) difference between maximum and minimum within a time window, (3) the value of the trend within a time window, (4) the change in the trend values from one window to the next, (5) the change in the difference between maximum and minimum within a time window from one window to the next, or (6) area within the maximum envelope and the minimum envelope.