Pablo Cruces1,2, Diego Moreno1, Sonia Reveco1, Yenny Ramírez1, Franco Díaz1,3

1Unidad de Paciente Crítico Pediátrico, Hospital El Carmen de Maipú, Santiago, Chile
2Centro de Investigación de Medicina Veterinaria, Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, Santiago, Chile
3Facultad de Medicina, Universidad Finis Terrae, Santiago, Chile

Keywords: Acute respiratory distress syndrome, COVID-19, hypoxemia, lung protective ventilation, mild hypothermia


We report the feasibility of a combined approach of very low low tidal volume (VT) and mild therapeutic hypothermia (MTH) to decrease the ventilatory load in a severe COVID-19-related acute respiratory distress syndrome (ARDS) cohort. Inclusion criteria was patients ≥18 years old, severe COVID 19 related ARDS, driving pressure ∆P >15 cmH2 O despite low-VT strategy, and extracorporea therapies not available. MTH was induced with a surface cooling device aiming at 34°C. MTH was maintained for 72 h, followed by rewarming of 1°C per day. Data were shown in median (interquartile range, 25%–75%). Mixed effects analysis and Dunnett’s test were used for comparisons. Seven patients were reported. Ventilatory load decreased during the first 24 h, minute ventilation (VE) decreased from 173 (170–192) to 152 (137–170) mL/kg/min (P = 0.007), and mechanical power (MP) decreased from 37 (31–40) to 29 (26–34) J/min (P = 0.03). At the end of the MTH period, the VT, P, and plateau pressure remained consistently close to 3.9 mL/kg predicted body weight, 12 and 26 cmH2 O, respectively. A combined strategy of MTH and ultraprotective mechanical ventilation (MV) decreased VE and MP in severe COVID-19-related ARDS. The decreasing of ventilatory load may allow maintaining MV within safety thresholds.

How to cite this article: Cruces P, Moreno D, Reveco S, Ramírez Y, Díaz F. Ventilatory load reduction by combined mild hypothermia and ultraprotective mechanical ventilation strategy in severe COVID-19-related acute respiratory distress syndrome: A physiological study. Turk J Emerg Med 2024;24:117-21.

Author Contributions

PC and FD conceived the study, designed the study, analyzed data, wrote the preliminary draft, had full access to all the data in the study, and took responsibility for the integrity of the data and the accuracy of the data analysis. DM, SR, and YR collected and curated data, analyzed data, and edited and reviewed the final manuscript. All authors read and approved the final manuscript.

Conflict of Interest

None Declared.

Financial Disclosure



We are deeply grateful to healthcare workers and pediatric teams worldwide, especially the Unidad de Paciente Crítico Pediátrico at Hospital el Carmen de Maipú, Chile, for their courage, professionalism, and dedication to patient care during the COVID‑19 pandemic.