Front. Nutr. Front. Nutr. Factors associated with the need of parenteral nutrition in critically ill patients after the initiation of enteral nutrition therapy Lopez-Delgado Juan Carlos Servia-Goixart Lluís Grau-Carmona Teodoro Bordeje-Laguna Luisa Portugal-Rodriguez Esther Lorencio-Cardenas Carolina Vera-Artazcoz Paula Macaya-Redin Laura Martinez-Carmona Juan Francisco Marin Corral Judith Flordelís-Lasierra Jose Luis Seron-Arbeloa Carlos Universidad de Zaragoza Alcazar-Espin Maravillas de las Nieves Navas-Moya Elisabeth Aldunate-Calvo Sara Nieto Martino Beatriz Martinez de Lagran Itziar 2023 research-article