A system for displaying trends and variability in a physiological dataset, comprising: a patient monitoring device; at least one sensor coupled to the patient monitoring device; a processor contained within the patient monitoring device and receiving patient data from the at least on sensor; a screen contained within the patient monitoring device and receiving display information from the processor; and at least one of an audible or visual alarm, wherein the alarm is triggered upon a predetermined condition in the variability or trend of the physiological dataset being met, wherein the predetermined condition is based on at least one of: difference between maximum and minimum within a time window, the value of the trend within a time window, and area within the maximum envelope and the minimum envelope wherein the processor: obtains the physiological dataset from the at least one sensor; applies a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset; applies a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset; outputs a real-time graph of the trend of the physiological dataset to the screen; and outputs a real-time graph of the variability of the physiological dataset to the screen 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. a patient monitoring device; at least one sensor coupled to the patient monitoring device; a processor contained within the patient monitoring device and receiving patient data from the at least on sensor; a screen contained within the patient monitoring device and receiving display information from the processor; and at least one of an audible or visual alarm, wherein the alarm is triggered upon a predetermined condition in the variability or trend of the physiological dataset being met, wherein the predetermined condition is based on at least one of: difference between maximum and minimum within a time window, the value of the trend within a time window, and area within the maximum envelope and the minimum envelope difference between maximum and minimum within a time window, the value of the trend within a time window, and area within the maximum envelope and the minimum envelope wherein the processor: obtains the physiological dataset from the at least one sensor; applies a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset; applies a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset; outputs a real-time graph of the trend of the physiological dataset to the screen; and outputs a real-time graph of the variability of the physiological dataset to the screen 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. obtains the physiological dataset from the at least one sensor; applies a smoothing algorithm to the physiological dataset to obtain a trend of the physiological dataset; applies a variability algorithm to the physiological dataset to obtain the variability of the physiological dataset; outputs a real-time graph of the trend of the physiological dataset to the screen; and outputs a real-time graph of the variability of the physiological dataset to the screen 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.