Evaluation of Preoxygenation at Three Different Altitudes Using Blood Gas Results: A Multicenter Propective Observational Study

Abstract

Introduction: Protecting patients from hypoxia during anesthesia induction is crucial for those undergoing coronary artery bypass surgery. High altitude does not change the inspired O2 concentration (%21), but reduced barometric pressure leads to decreased partial alveolar pressure and arterial PO2. We aim to evaluate the effects of preoxygenation in the operating room at three different altitudes. Methods: After obtaining ethical approval, patients aged 40 and above, living in the same city for at least 10 years, and scheduled for coronary artery bypass surgery will be included in the study. A total of 60 patients will be divided into three groups: Group 0, Group 800, and Group 1900, with 20 patients in each group corresponding to three different altitudes. Before anesthesia induction, patients will receive 12 L/min of 80% O2 for 3 minutes via a face mask. During preoxygenation, arterial blood gas values will be recorded at the 0th, 1st, 2nd, and 3rd minutes. PaO2 values from arterial blood gas results will be evaluated at these time points across the three altitudes. Results: There were no statistically significant differences between the groups regarding height, weight, age, and ASA classifications. There were no statistically significant differences in pO2 values between the 0th, 1st, 2nd, and 3rd-minute blood gas measurements across all groups (p>0.05). Conclusion: Preoxygenation before anesthesia induction for patients undergoing coronary artery bypass surgery produced similar results at all three different altitudes.

Keywords

• Blood Gas
• Preoxygenation
• Different Altitudes

References

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