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Normothermic Negative Pressure Ventilation Ex Situ Lung Perfusion: Evaluation of Lung Function and Metabolism
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[Fatal pulmonary embolism with a normal PaO2]
Annales De Medecine Interne
|January 1, 1983
Summary
Massive pulmonary embolism can occur without low blood oxygen. Treatment with dobutamine can worsen hypoxemia by increasing venous admixture due to improved cardiac output.
Area of Science:
- Cardiology
- Pulmonology
- Critical Care Medicine
Background:
- Massive pulmonary embolism (PE) is a life-threatening condition.
- Hypoxemia is a common but not universal finding in massive PE.
- The physiological response to PE can be complex and vary between patients.
Observation:
- A case of massive PE was reported.
- The patient presented without arterial hypoxemia (PaO2 = 109 torr on room air).
- Diagnosis was confirmed by angiography and necropsy.
Findings:
- Massive PE can exist in the absence of hypoxemia.
- Dobutamine administration led to increased venous admixture.
- Improved cardiac output from dobutamine contributed to the onset of hypoxemia.
Implications:
- This case highlights the importance of considering PE even with normal blood oxygen levels.
- Physicians must be aware of potential iatrogenic hypoxemia during PE treatment.
- Careful monitoring of gas exchange is crucial when using inotropes in PE patients.
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