PULMONARY EMBOLISM-ABG

SUMMARY

1. Only in the absence of cardiopulmonary disease and if the patient is not on oxygen and is not hyperventilating is there a satisfactory specificity for diagnosing a PE solely from an elevated A-a gradient.

2. Hypoxemia, after a large PE, is due to many factors­ especially (1) V/Q mismatch, (2) R-to-L shunt, (3) dead space.

3. Secondary right ventricular failure can also contribute to the V/Q mismatch.

Reference(s)

Wilkinson, I., Furmedge, D. and Sinharay, R. (2017). Oxford handbook of clinical medicine. Oxford: Oxford University Press. Get it on Amazon.
Feather, A., Randall, D. and Waterhouse, M. (2020). Kumar And Clark’s Clinical Medicine. 10th ed. S.L.: Elsevier Health Sciences. Get it on Amazon.
Hannaman, R. A., Bullock, L., Hatchell, C. A., & Yoffe, M. (2016). Internal medicine review core curriculum, 2017-2018. CO Springs, CO: MedStudy.
Therapeutic Guidelines. Melbourne: Therapeutic Guidelines Limited. https://www.tg.org.au [Accessed 2021].