The Emergency Room (ER) is a high-pressure environment where medical procedures require effective team communication and timely decision-making to ensure high-quality patient care. Research shows that augmented reality head-mounted displays (AR-HMDs) can improve decision-making by reducing cognitive load and enhancing shared mental models primarily in well-controlled healthcare settings such as surgery and operations management. Despite their potential benefits, limited research exists on the design of AR-HMDs for action teams including what, how, and when interfaces with decision-making information can facilitate coordination among teams in ER procedures. To address this gap, we conducted a participatory design study with healthcare workers in a virtual hospital environment to co-create low-fidelity AR-HMD interfaces for role identification, time tracking, and dosage calculation applications.