The healthcare industry is a major contributor to global carbon footprint, with hospitals playing a key role in promoting low-carbon strategies to mitigate climate change. This study introduces a dynamic assessment model for the life cycle carbon footprint of hospitals, improving upon previous studies that focused only on specific stages. The model includes five components: goal and scope definition, Building Information Modeling (BIM) module, dynamic inventory database, dynamic calculation, and interpretation. To improve accuracy, the model integrates multiple data sources, including BIM, public databases, relevant reports and literature, surveys, historical record, and geographic information systems (GIS). The model also integrates four dynamic factors, detailing their role in establishing the inventory dataset of dynamic consumption and carbon footprint factors. The applicability and accuracy of the model were validated through a case study of an emergency complex in Shanghai, where dynamic factors were shown to significantly affect the hospital's carbon footprint (48 %). The case study revealed that the operation stage was the largest contributor (73.1 %) to the total carbon footprint, with medical equipment systems accounting for 43.3 % and conventional energy-consuming systems contributing more than 50 %. This study provides a more accurate and comprehensive method for assessing the carbon footprint of hospitals, offering critical insights for decision-making on carbon reduction initiatives.