Presentation is loading. Please wait.

Presentation is loading. Please wait.

CT Imaging Issues in the Critically Ill E. Wiebe, MD, FRCPC Department of Radiology University of Alberta.

Similar presentations


Presentation on theme: "CT Imaging Issues in the Critically Ill E. Wiebe, MD, FRCPC Department of Radiology University of Alberta."— Presentation transcript:

1 CT Imaging Issues in the Critically Ill E. Wiebe, MD, FRCPC Department of Radiology University of Alberta

2 I have no financial or other disclosures CT Imaging Issues in the Critically Ill

3 Imaging Issues and Strategies  Patient selection  Region of interest  Use of contrast IV contrast  Use of oral contrast  Contrast risk  Radiation risk

4 Imaging Issues and Strategies  Patient selection  Clinical findings  Prior imaging findings  Imaging limitations and access  Relative contraindications

5 Imaging Issues and Strategies  Patient selection  Region of interest  Clinical findings  Mechanism of injury  Previous imaging findings

6 Imaging Issues and Strategies  Noncontrast exam  Acute retroperitoneal hemorrhage  Bone injuries  Aortic dissection or rupture  IV Contrast use  Vascular injuries and diseases  Solid organ assessment  Bowel wall assessment

7

8

9

10

11 Imaging Issues and Strategies  Oral contrast use  Positive contrast (eg. Telebrix or Gastrografin  Demonstates bowel leak  Impairs bowel wall assessment  Variable lumen distention  Negative contrast (eg. Water or Polyethylene glycol solution)  Better assessment of bowel wall  Cannot identify bowel leak

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39 Imaging Issues and Strategies  Contrast risk  Anaphylactoid reaction  Nephrotoxicity

40 Imaging Issues and Strategies  Anaphylactoid reaction  Dose and concentration independent  Screen patients for increased risk  Preventative premedication with corticosteroids and antihistamines  No correlation or association with shellfish allergy and povidone-iodine skin cleansing solution

41 Imaging Issues and Strategies  Nephrotoxicity  recent meta-analysis suggested that the risk of contrast-induced nephrotoxicity is less than previously suggested (Radiology 2010; 256:21–28)  Most recent study concludes that there is increased risk in patients with estimated GFR of <40ml/min (Radiology 2013: 268:719-28)

42 Imaging Issues and Strategies  Nephrotoxicity  Dose dependent  Intravenous hydration is most important preventative measure  Consider benefit of noncontrast scan

43 Imaging Issues and Strategies  Radiation dose and risk  Main concern is induction of cancer  ALARA principle  Recognize the relative risk of CT and radiography  Use technology advances made to decrease dose

44 Imaging Issues and Strategies  Radiation dose  Measured as effective dose in mSV  Background radiation dose: 3mSv/yr  Standard CT abdomen dose: 8-10mSv for single scan  Low dose exams decrease dose to 2- 4mSv/scan

45 Imaging Issues and Strategies  Radiation dose  Dose estimate based on dose-length product (DLP) which is given with each scan  Chest CT dose = x DLP  Abdomen CT dose = x DLP  Head CT dose = x DLP  Neck CT dose = x DLP

46 625 x = 9.37 mSv 659 x = 9.88 mSv 630 x = 9.45 mSv Total effective dose = 28.7 mSv Imaging Issues and Strategies

47 Total effective dose = 166 x = 2.82 mSv Imaging Issues and Strategies

48  Tailor exam to clinical situation  Use intravenous and oral contrast when necessary but not always  Be aware of risks of imaging

49 Questions?


Download ppt "CT Imaging Issues in the Critically Ill E. Wiebe, MD, FRCPC Department of Radiology University of Alberta."

Similar presentations


Ads by Google