Chest
Clinical Investigations: Pulmonary EmbolismArterial Blood Gas Analysis in the Assessment of Suspected Acute Pulmonary Embolism
Section snippets
Clinical Data
Patients in this investigation participated in the national collaborative investigation Prospective Investigation of Pulmonary Embolism Diagnosis (PIOPED).5 The eligible population consisted of patients 18 years of age or older in whom acute PE was suspected. Symptoms of PE were required within 24 h of entry into the study. In the present investigation, we included only patients who had PE diagnosed or excluded by pulmonary angiography.5 We evaluated patients randomized for pulmonary
Negative Predictive Value of Blood Gas Values in Combination With Alveolar-Arterial Oxygen Pressure Difference
Among patients with no prior cardiopulmonary disease, PE was absent in 69% or fewer with a PaO2 of 80 mm Hg or more, PaCO2 of 35 mm Hg or higher, or a P(A-a)O2 of 20 mm Hg or less, or all three indicators (Table 1). Even with values of PaO2 of 80 mm Hg or more, PaCO2 of 35 mm Hg or more, and P(Aa)O2 gradient of 20 mm Hg or less, 26 of 42 (62% [95% CI, 46 to 76%]) did not have PE. Conversely, in patients who did not have prior cardiopulmonary disease, PE was present in 16 of 42 (38% [95% CI, 24
DISCUSSION
No combinations of blood gases were identified that reliably excluded PE. Although most patients with PE have a low PaO2, low PaCO2, or high P(A-a)O2 gradient, as has been observed by others,4 the absence of such abnormal values, alone or in combination, did not exclude PE. Evaluation of blood gases, therefore, may contribute to the formulation of a clinical assessment, but blood gases are of insufficient discriminant value to permit exclusion of the diagnosis of PE.
In the evaluation by
REFERENCES (12)
- et al.
Clinical, laboratory, roentgenographic and electrocardiographic findings in patients with acute pulmonary embolism and no pre-existing cardiac or pulmonary disease
Chest
(1991) - et al.
Alveolar-arterial oxygen gradient in the assessment of acute pulmonary embolism
Chest
(1995) - et al.
Is pulmonary angiography essential for the diagnosis of acute pulmonary embolism?
Am J Surg
(1979) - et al.
Improved use of arterial blood gas analysis in suspected pulmonary embolism
Chest
(1989) - A collaborative study by the PIOPED investigators. Value of the ventilation/perfusion scan in acute pulmonary embolism:...
- et al.
Cited by (172)
Risk scoring models fail to predict pulmonary embolism in trauma patients
2021, American Journal of SurgeryPrevalence and risk factors for pulmonary embolism in patients with suspected acute exacerbation of COPD: a multi-center study.
2020, European Journal of Internal MedicineThe problem of under-diagnosis and over-diagnosis of pulmonary embolism
2019, Thrombosis ResearchCitation Excerpt :Importantly, ABG analysis results are neither sensitive nor specific for PE. The presence of a normal alveolar-arterial oxygen gradient (A-a O2) is an equally likely finding in patients with and without PE, and is therefore not of use in excluding the condition [32,33]. Hypoxia (PaO2 <80 mm Hg) and hypocapnia (PaCO2 <35 mm Hg) are suggestive of PE, although these findings are absent in a large proportion of PE patients [32].
Acute and chronic pulmonary embolism: Perspectives on diagnosis and management
2018, Cardiovascular Thrombus: From Pathology and Clinical Presentations to Imaging, Pharmacotherapy and InterventionsPulmonary Thromboembolism
2015, Murray and Nadel's Textbook of Respiratory Medicine: Volume 1,2, Sixth EditionManaging pulmonary embolism from presentation to extended treatment
2014, Thrombosis Research
revision accepted July 1