Rapid response systems are being introduced to anticipate sudden changes in hospitalized patients, but it is impossible to predict all sudden changes. In order to respond to unanticipated emergencies, it is necessary to establish a response procedure in advance, and in addition, it is necessary to have a simple, fast, and easy way to document the emergency. Before the implementation of the system, patients tended to record their treatment after they had settled down, often from notes or memory, and detailed records of their treatment were not kept. This system enables fast recording of medical procedures under urgent circumstances by optimizing the distribution of frequently used items with one-click entry and free-text entry for the parts that need to be described. The recorded information is saved as an electronic medical record. We evaluated the effectiveness of the system by comparing the quality of entries with and without the system.The average number of words in the records when the system was used was 810, and the average number of acts (number of entries) was 23 .0 items. When the system was not used, the average number of words in the medical record was 317, and the average number of acts was 13.4. When the system was used, the number of records for sudden changes increased about twice as much. One problem was the need to familiarize staff called in for emergencies with the use of the system.