Recently, when the disaster occurred, the lifesaving emergency method that was called triage are being introduced. Purpose of triage is to decide the lifesaving order from patient's condition and to save more preventable deaths. The sensor network is constructed by using the computerized tag, and the research of the emergency lifesaving support system that observes and collects information on patient is active. We state this network as triage network. When the data of patient is collected through the sensor network, it is necessary to consider battery power of the sensor node. If the battery ran out, not only the patient data measured with the node is not obtained but also the relaid data is lost. In this paper, we propose N2LE, combining delayedRREP by estimated lifetime and triggeredRREQ. The purpose of N2LE is to reduce the difference between node lifetime and network lifetime that is caused by battery problem. Battery that can be used in delayedRREP by estimated lifetime for the network is quantified and reflects it in the route. When the change takes place in the battery environment, the route is restructured in triggeredRREQ. We evaluate our proposal using simulations, and results show that our proposal achieves longer network lifetime while node lifetime kept similar.