Nowadays, the issue of system resilience on candidates' safety application has been raised in the rapidly increasing sensor-dependent smart city applications, especially medical application. For instance, if the medical data traffic is jammed by numerous interferers (possibly other sensors), the system should instantly retain the communication to keep the candidates being monitored in safe. In this paper, a resilient safety LPWAN (RS-LPWAN) has been developed for ubiquitous medical applications. First, proposed RS-LPWAN is based on NB-IoT with characteristics of low power consumption, high data capability etc. Then, system resilience is a top priority in medical applications to protect candidate safety. Thus, a RS-LPWAN is designed and optimized with maximized transmission rate and minimized transmission delay. Risk assessment on RS-LPWAN was performed through Monte Carlo analysis on randomizing the working environment. The results demonstrated that proposed RS-LPWAN can accomplish (1) >1.8kbs transmission rate, (2) <0.38 second latency in all scenarios. As a result, the proposed RS-LPWAN is sufficient to guarantee the candidate safety in medical networks.