Introduction: The COVID 19 pandemic has come to change paradigms in terms of ventilatory support measures worldwide, prone ventilation was shown to decrease mortality in patients with ARDS. Objective:To identify the difference in days of mechanical ventilation of patients with respiratory failure by COVID-19 In the Intensive Care Unit with prone position for £48 hours compared to >48 hours. Material and methods: We evaluated all patients admitted to the Intensive Care Unit of UMAE Hospital No. 1 de Especialidades del Bajío, who required mechanical ventilation and prone position for refractory acute respiratory failure due to SARS-CoV-2 infection, we identified those in prone position for £48 hours versus > 48 hours (h), and we evaluated the difference in days of mechanical ventilation between the two groups, concluding who maintained more days of mechanical ventilation. Results: Statistical significance was found only for the following variables: days of mechanical ventilation (p=<0.001), days of ICU stay (p=0.04), time in prone position (p=0.001) and PaO2/FiO2 ratio after maintaining prone position (p=<0.001). Conclusion: The improvement in the oxygenation index in prone position >48 h is greater compared to those who remained £48 h, however, the time (days) under mechanical ventilation was less in the £48 h group; complications had no impact on the time in prone position.