Intensive care comes with the risk of incidents that can have significant impact on patient health. Extracorporeal membrane oxygenation (ECMO) is important when supporting heart and lung function. However, problems with the device can cause delays in treatment, as perfusionists often need to be on site to troubleshoot. Augmented Reality (AR) provides a solution to bridge these waiting times and increase patient safety. The aim of this study is the user-centered development of an AR-application for improved communication between intensive care nurses and perfusionists via remote assistance. Therefore, intensive care nurses use a Microsoft HoloLens 2 (HL2) and perfusionists a tablet. The application is developed in accordance with VDI guidelines 2221 and 2222. Audio and video transmission as well as holographic markings are identified as system functions using the black box method. The developed solutions are organised using a morphological box and evaluated based on predefined criteria. Unity is used for implementation, so that audio and video transmission can be realised using Unity assets. The graphical user interface is customised for HL2 and tablet, with a focus on functionality and user-friendliness. The application provides remote assistance during ECMO and meets all functional requirements. Technical limitations of HL2, such as difficulties with gesture recognition and hologram placement, have been identified and should be improved. Next steps include the evaluation of user acceptance and functionality in clinical tests as well as iterative application development. Successful deployment could improve work processes in intensive care medicine and reduce the workload on staff.