Application of the Lean Principles of the Toyota Production System for the Improvement of the Emergency Service Attention Times of a High Complexity Hospital/Aplicación de los principios Lean del sistema de producción Toyota para la mejora de los tiempos de atención del servicio de urgencias de un hospital de alta complejidad/Aplicação dos rincípios Lean do sistema de produção Toyota para a melhoria dos tempos de atenção de serviço de emergência de um hospital de alta complexidade

Context: Toyota Production System is a way to discover opportunities for improvement, adaptation and change, through lean tools, in companies that are in conditions of constant change. Aim: The objective of this study was to apply the lean principles of the Toyota Production System to improve attention times in the emergency department of the Hospital Universitario San Ignacio in Bogota (Colombia). Methods: A mixed design was used in this study: First, a situational diagnosis of the processes of the emergency service of the Hospital was established, later the institutional behavior patterns (attention cycle times and waiting times) were statistically determined and lastly, improvement strategies were proposed to be implemented in the short and long term. Results: Detailed knowledge of the service's operation was achieved. This study enabled the recognition of 13 general processes in the care route that varied according to the triage type, and areas with a greater flow of patients: information, triage, admissions, consulting room, sampling, and billing. Extended wait times were found in consulting room (109 min), sampling (29 min), x-rays(77 min), medical reassessments (160 min) and billing (18 min). Likewise, 23 activities that did not add value to the process were identified. Multiple improvement strategies were proposed with a special focus on three specific areas: admissions, sampling, and billing. Conclusions: The implementation of the lean principles in the health sector provide the guidelines for an adequate improvement plan of the emergency service, allowing for opportunities such as inclusions of just-in-time activities (continuous flow and kanban), standard work and levelling in the attention process. Keywords: Lean Manufacturing, Toyota Production System, Lean Healthcare, Colombia, Emergency Service. Contexto: el Sistema de Producción Toyota es una forma de descubrir oportunidades de mejora, adaptación y cambio, a través de herramientas lean, en empresas que se encuentran en condiciones de cambio constante. Objetivo: el objetivo de este estudio fue aplicar los principios lean del Sistema de Producción Toyota para mejorar los tiempos de atención en el servicio de urgencias del Hospital Universitario San Ignacio de Bogotá (Colombia). Métodos: en este estudio se utilizó un diseño mixto: Primero se estableció un diagnóstico situacional de los procesos del servicio de urgencias del Hospital, posteriormente se determinaron estadísticamente