The SentiLiter is a network-enabled system for monitoring changes in fluid level and rates of fluid flow specifically in IV infusion bags and catheter bags for medical patients. The system is designed to provide alerts to the appropriate caregivers remotely to reduce the need for them to check each bag manually, saving caregiver time and effort and improving overall patient care by having issues attended to more quickly. The alerts are intended to notify caregivers when IV or catheter bags will need service soon – typically when an IV bag is nearly empty or a catheter bag is nearly full – or there is a significant deviation or change in the flow rate of the fluid, which could indicate a problem with the fluid tubing or that a patient has begun to produce output into a catheter bag after surgery