Hernández RG, Cerón DU

Language: Spanish
References: 7
Page: 226-230
PDF size: 215.90 Kb.

ABSTRACT

Introduction: The degree to which it affects the ability of oxygenation in the lungs, is evaluated by indices that do not include the effect of interventions that can affect the outcome, regardless of the degree of lung injury. Recently described an equation that adjusts the PaO₂/FIO₂ with positive end-expirative pressure to improve the linear correlation with the DA-aO₂. Our purpose is to perform the work with local data and find the explanations of changes in the correlation.
Materials and methods: We prospectively included 91 mechanically ventilated patients in the Intensive Care Unit for a period of six months. We obtained arterial blood gas data for the calculation of the alveolar-arterial (DA-aO₂) PaO₂/FIO₂ relationship and obtained the value of positive end-expirative pressure when taking blood gases. Correlations were made between PaO₂/FIO₂ and DA-aO₂, with and without adjusting the positive end-expirative pressure as well as the equation reported by Sanchez et al (Ln [PaFi]/ [PEEP+12]).
Results: The linear correlation between PaO₂/FIO₂ and DA-aO₂ (r² = 0.67) increases in transforming PaO₂/FIO₂ to log values, with (r² = 0.75) or without (r² = 0.87) with positive end-expirative pressure adjustment proposed by Sanchez.
Conclusion: The increase in the linear correlation between the DA-PaO₂ and the PaO₂/FiO₂ and positive endexpirative pressure is set with the result of the logarithmic transformation and not by the added value of positive end-expirative pressure.

REFERENCES

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