Zhang Jian, Associate Chief Physician, Deputy Director of the Department of Critical Care Medicine Primarily engaged in the treatment of pediatric critical illnesses, with particular expertise in pediatric hemodynamic management, neurocritical care, and critical care ultrasound. Currently serves as a member of the Blood Purification Professional Committee of the Pediatric Critical Care Physicians Branch of the Chinese Medical Doctor Association, a member of the Severe Infection Collaboration Group of the Emergency Medicine Subcommittee of the Pediatrics Branch of the Chinese Medical Association, a member of the Critical Care Subcommittee of the Pediatric Diseases and Healthcare Branch of the Chinese Maternal and Child Health Association, a member of the Cardiopulmonary Resuscitation Subcommittee of the Emergency Physicians Branch of the Chinese Medical Doctor Association, a member of the Pediatrics Branch of the China Medical Rescue Association, a trainer of the Chinese Critical Care Ultrasound Study Group, and a member of the second batch of the Shanghai "Group-Type" Medical Aid Team to Tibet. Main research directions: Hemodynamic management in pediatric critical illness, multimodal management of neurocritical care, and the integration of critical care ultrasound with the diagnosis and treatment system in critical care.