Comparison Of SpO₂/FiO₂ And PaO₂/FiO₂ In ARDS Patients At Different Altitudes In Yunnan Province

Objective(s):Arterial oxygen partial pressure/oxygen concentration(PaO2/FiO2)is one of the important criteria for the diagnosis of acute respiratory distress syndrome(ARDS).The literature reports the pulse oximetry/oxygen concentration(SpO2/FiO2)has a good correlation with arterial oxygen partial pressure/oxygen concentration(PaO2/FiO2)in low altitude areas.SpO2/FiO2 can be used instead of PaO2/FiO2 to evaluate oxygenation in patients with ARDS,but arterial oxygen partial pressure is affected by altitude,with the increase of altitude,the partial pressure of arterial oxygen is gradually reduced,so we study the correlations between SpO2/FiO2 and PaO2/FiO2 in two different altitude regions,include Kunming,Yunnan Province and Shangri-La,Diqing Tibetan Autonomous Prefecture,Yunnan Province.to investigate whether SpO2/FiO2 can be used instead of PaO2/FiO2 to assess oxygenation in patients with ARDS.Methods:Data from ARDS patients admitted to the Department of Critical Care Medicine,First Affiliated Hospital of Kunming Medical University and the Department of Critical Care Medicine,People’s Hospital of Diqing Tibetan Autonomous Prefecture,Yunnan Province from January 2019 to March 2019,and the health of the People’s Hospital of Diqing Tibetan Autonomous Prefecture,Yunnan Province were collected.Medical staff information.The patients were divided into three groups according to the altitude.The first group was the ARDS patients(n=24,271 blood gas analysis)of the First Affiliated Hospital of Kunming Medical University,and the second group was the ARDS of the People’s Hospital of Diqing Tibetan Autonomous Prefecture,Yunnan Province.The patient(n=14,47 blood gas analysis),the third group was the healthy medical staff of Yunnan Provincial People’s Hospital of Diqing Tibetan Autonomous Prefecture(n=44).Patients in the first and second groups of ARDS were given a lower inhaled oxygen concentration to maintain SpO2 90%-96%greater than 30 minutes,collect SpO2,FiO2,PaO2,and the three data are completed within 5 minutes of each other.using the Spearman index to the first Correlation analysis between the group and the second group of SpO2/FiO2 and PaO2/FiO2 was carried out,and linear equation between SpO2/FiO2 and PaO2/FiO2 was derived by linear analysis.The third group is Yunnan’s health care workers in the People’s Hospital of Diqing Tibetan Autonomous Prefecture.The group mainly observes the SpO2 of the normal population in Shangri-La,Diqing Tibetan Autonomous Prefecture,Yunnan Province.Only the mesn ± standard deviation(SD)of SpO2 is calculated in the study.Results:In this prospective study,the first group of 24 patients included 271 blood gas analyses.The study found that SpO2/FiO2 and PaO2/FiO2 have a strong linear relationship and can be described by a linear regression equation:SpO2/FiO2=58+0.97 X PaO2/FiO2(p<0.05,r=0.83).The second group of 14 patients included 47 blood gas analysis.SpO2/FiO2 and PaO2/FiO2 also have a strong linear relationship,which can be described by linear regression equation:SpO2/FiO2=6+2.13 X PaO2/FiO2(p<0.05,r=0.938).The third group was included in the health care workers of the People’s Hospital of Shangri-La,Diqing Tibetan Autonomous Prefecture,Yunnan Province.The mean ± standard deviation(SD)of SpO2 was(94 ± 1.4)%.Conclusion(s):SpO2/FiO2 and PaO2/FiO2 in ARDS patients in Kunming,Yunnan Province and Shangri-La,Diqing Tibetan Autonomous Prefecture,Yunnan Province have a strong correlation,SpO2/FiO2 can be used instead of PaO2/FiO2 to evaluate the oxygenation of ARDS patients.