Select a Community
Are you sure you want to trigger topic in your Anconeus AI algorithm?
You are done for today with this topic.
Would you like to start learning session with this topic items scheduled for future?
Fluid LDH:serum LDH ratio of 0.5:1
15%
22/143
Fluid LDH of 50 IU/L (normal <300)
8%
12/143
Fluid protein:serum protein ratio of 0.6:1
50%
72/143
Fluid protein of 10 g/L (normal <25)
A gram stain is needed in order to evaluate this question
6%
9/143
Select Answer to see Preferred Response
This patient's chest X-ray shows a pleural effusion. Pleural effusions secondary to esophageal tears are exudative in nature, consistent with a fluid:serum protein ratio of >0.5:1 by Light's Criteria. Pleural effusions can be classified as transudates or exudates based on Light's Criteria (Illustration A), which has a sensitivity of 98% and specificity of 80%. Light's criteria states that an effusion is an exudate if analysis of the effusion fluid shows at least one of the following: (1) effusion:serum lactate dehydrogenase (LDH) ratio of at least 0.6, (2) effusion LDH content more than 2/3rds of the normal limit of serum LDH, and (3) effusion:serum protein ratio of at least 0.5. Exudates occur when the pleural vasculature losses its integrity, where as transudates occur when there is an imbalance between oncotic and hydrostatic forces. Porcell and Light discuss the diagnostic approach to pleural effusions. They note that posterolateral and anterior chest X-rays are usually adequate to evaluate an effusion, but a CT scan can be used if X-rays are unclear. Most exudative effusions are caused by pneumonia, tuberculosis, pulmonary embolism, or cancer. Davies et al. conducted an unblinded, randomized controlled trial to evaluate the use of an indwelling pleural catheter vs. a chest tube and pleurodesis for patients with pleural effusion due to malignancy. Indwelling pleural catheters are smaller than chest tubes, and can remain inside the patient after discharge. They found no significant difference in patient-reported dyspnea or quality of life between the two treatments. Figure A is a radiograph showing a left-sided pleural effusion. Illustration A lists Light's Criteria for evaluation of a pleural effusion. Illustration B shows a flow-chart for guiding work-up of a pleural effusion. Incorrect Answers: Answers 1, 2, 4: These data suggest a transudative effusion. Answer 5: Gram stain is not needed to determine whether an effusion is transudative or exudative, but may be helpful to determine the microbiological character of an effusion.
2.6
(16)
Please Login to add comment