A vital sign monitoring system that can be used with multiple patients and utilizes historic patient data information for the patient to optimize the process of obtaining current vital sign measurements. Each patient is identified with a unique patient identification device that is automatically detected by the vital sign monitor. The vital sign monitor communicates with a medical records database and obtains historic patient data information and previously diagnosed characteristics for the patient identified by the patient identification device. The historic patient data information and previously diagnosed characteristics of the patient can be utilized by the vital sign monitor to set alarm limits for the vital sign measurements and automatically adjust the blood pressure estimation algorithm of the NIBP monitor.