Point of Care Ultrasound UCSF Continuing Medical Education October - PowerPoint PPT Presentation

Point of Care Ultrasound UCSF Continuing Medical Education October 21-22, 2018

Disclosure I have no relevant financial relationships with any companies related to the content of this course.

Lung Ultrasound and Thoracentesis Stephanie Conner, MD UCSF Medical Center at Parnassus Heights 3

Objectives • Basic principles of lung ultrasound • Key findings with lung ultrasound • Overview of thoracentesis 4

Probe Selection 10-15 MHz Linear Phased Array Curvilinear 25 mm 5

Patient Position Chest. 2011;140(5):1332-1341. doi:10.1378/chest.11-0348 6

Hospitalized Patient Technique Interstitial findings • • Anterior: A or B lines Lateral Bases: normal to • have some B-lines Look for effusions • Probe orientation • • Vertical (longitudinal) • Midclavicular line � posterior axillary line Used with permission from Arun Nagdev

Findings on lung ultrasound • Normal Lung • Alveolar and interstitial changes (pulmonary edema, fibrosis, etc.) • Consolidation • Pleural Effusion • Pneumothorax 8

Findings, continued A-Lines B-lines Pneumothorax Effusions Consolidations 9

A Lines and B Lines • Curvilinear or Phased Array Probe • Increase Gain • Depth 12-16cm 10

Normal Lung • Normal aerated lung scatters ultrasound waves, can’t be seen • A-lines are horizontal hyper echoic lines representing artifact: reverberations between the highly reflective pleura and transducer 11

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A lines = non-thickened interstitial septa 13

Alveolar Interstitial Changes • Widening of the interlobular septa allows for propagation of ultrasound waves and the formation of b-lines. • Seen in pulmonary edema, PNA, ARDS, ILD 14

“B” Lines Rib Rib Tissue Air/Water Interface 15

Move with lung sliding Arise from the pleural line 3 per rib space Well-defined B lines = interstitial Reach screen edge syndrome Acute Interstitial Syndrome 16

Lung US: Dynamic Monitoring Liteplo et al. Real-time resolution of sonographic B-lines in a patient with pulmonary edema on CPAP. AJEM (2010) Case: Hx CHF, ESRD, • dyspnea, orthopnea Initial US: Diffuse B-lines • After CPAP x 3.5hrs: A-lines • 17

Review A-lines vs B-lines A -Lines B -Lines Which Probe? Curvilinear or Phased Array Scan Where? Anterior Midclavicular CHF PNA What are B-lines? Interstitial Syndrome ARDS Are B-lines pathologic in lateral zones? Fibrosis NO! 18

Alveolar Consolidation • “Hepatization of lung” • 98.5% PNAs abut pleura • US vs CT: 
 (Lichtenstein 2007) • Sens: 0.91 • Spec: 0.98 19

Case: 50 y/o male with cough & fever Liver 20

Pleural Effusion • Identification of a hypoechoic or echo-free space surrounded by typical anatomic boundaries: • diaphragm (and abdominal organs) • chest wall • Ribs • visceral pleura • normal/consolidated/atelectatic lung 21

Positioning Start South then Go North 22

RUQ/Perihepatic view: Normal Morison’s Pouch Diaphragm Costophrenic Recess 23

Pleural Effusion 24

Pleural Effusion • US more sensitive than XR or exam: Exam > 300mL • CXR >200mL • • US > 20 mL 
 Liver Effusion • Scan dependent zones 
 Fluid is hypoechoic (black) • • Large effusions generally more symptomatic Lung 25

Simple vs complex effusions 26

Consolidation and Effusion Summary • More sensitive than physical exam or X-ray • Faster to acquire than CXR • Less radiation 27

Pneumothorax 28

Probe Selection 10-15 MHz Linear Curvilinear 25 mm 29

Normal Lung: Sliding Visceral Pleura Rib Alveoli Rib Shadow Slide used with permission of Arun Nagdev 30

Is Pleural Sliding Present? 31

Pneumothorax Is Pleural Sliding Present? 32

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Normal M-mode of Lung Soft Ocean Tissue Normal Beach Lung 34

Abnormal Lung M-mode: PNEUMOTHORAX Soft Tissue Ocean / Barcode Abnormal Lung 35

Confirm: M-Mode OVERVIEW No Pneumothorax Pneumothorax Ocean + Beach Ocean 36

The Lung Point • Sensitivity: 0.66 • Specificity: 1.00 (Lichtenstein 233 ICU pts vs CT) 37

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US: Pneumothorax • Outperforms CXR in supine patients • Much higher sensitivity, similar specificity • Lower specificity critically ill ICU patients • False positives with pulmonary scarring, TB, ARDS (specificity 60-91%) • Lung Point: 100% specificity 39

Lung US Review • A-Lines: R/O CHF. Likely COPD/PE/Normal • B-Lines: Diffuse: CHF, ARDS, PNAs. • B-Lines: Focal: PNA • Hepatization likely consolidation • Effusions: scan posterior and lateral bases. Find the diaphragm! • Pneumothorax: absence of lung sliding, lung point highly specific 40

Thoracentesis 41

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US Guidance in Thoracentesis • Find fluid on ultrasound • Establish landmarks for safe needle insertion with adequate depth • Usually not done under direct US guidance • Check for lung sliding after the procedure 43

Safe for thoracentesis? 44

Safe for thoracentesis? 45