2010.11.04 Critical Care/ ER Chest X Ray Discussion

1.    How to ddx AP view or PA view?
Ans:
•    Scapular Spine
•    C spine morphology: if PA, due to mild neck extension, 看起來可能像一個倒v尖端向上的飛鏢狀。If AP, vertebral body 則多成長方形。

2.    Status post Endo, followed CxR, if one lung white out, do check the position of endotracheal tube first.

3.    How to ddx the white out lung caused by extrapleural lesion, like hemimediastinum, or intrapulmonary lesion, like collapse, pneumonia? ( not too difficult, basic question)

4.    On ETT, then fever, bollowed CxR, which initially present one lung white out then bilateral. → aspiration pneumonia.
(There is no guarantee of exclusion of aspiration pneumonia after ETT, esp when pt also on NG tube. )

5.    Double (bronchial) wall sign, one sign for penumomediastinum （下圖左側支氣管）. The most important thing to ddx pneumothorax: notice whether there is lung marking at the least dependent part of lung field. (ex: when standing or sitting, apex. When supine, sulcus.)

http://radiographics.rsna.org/content/20/4/1043.full?sid=a4123d96-94e1-4577-98a2-4ff395739a47 (cited from)

6.    One Case. K.P liver abscess with septic emboli, on ETT.
Sudden onset desaturation: thick of barotrauma, lower PEEP.

7.    Naclerio's V Sign. Pneumomediastinum.
Reference: doi: 10.1148/radiol.2451042197 October 2007 Radiology, 245, 296-297

8.    Vascular Pedicle Width. 有興趣的朋友可以自行google。主要協助判斷intravascular fluid status.
Other reference: http://ccforum.com/content/11/S2/P291

9.    Pneumothorax, s/p Chest tube insertion. Recurrent SOB. Ddx: re-expansion pulmonary edema should be ruled out.
Reference:
N Engl J Med 2006; 354:2046 May 11, 2006
Ann Thorac Surg 2005;80:1933-1934

10.    Neurogenic pulmonary edema. Pt with Brain Trauma history, but no rib fracture.
Reference:
Emedicine.