Korean J Crit Care Med.  2016 Feb;31(1):4-9. 10.4266/kjccm.2016.31.1.4.

Lung Ultrasound in Critically Ill Patients

• Lee J

• KMID: 2227606
• DOI: http://doi.org/10.4266/kjccm.2016.31.1.4

Abstract

Lung ultrasound (LUS) is an emerging tool for intensivists to diagnose and monitor thoracic diseases of critically ill patients. It is easily applied at the bedside in real time and is free of radiation hazards. In the intensive care units (ICUs) lung ultrasound can be used to diagnose pneumothorax and interstitial syndrome. It can also be used to monitor changes in the lung. However, the major limitations of LUS is that it is highly operator dependent and cannot be applied in patients with thoracic dressings, subcutaenous emphysema or pleural calcifications. This article reviews the basic principles of lung ultrasound and discusses how it can be used in ICUs.

Keyword

intensive care units; lung ultrasound

MeSH Terms

Bandages
Critical Illness*
Emphysema
Humans
Intensive Care Units
Lung*
Pneumothorax
Thoracic Diseases
Ultrasonography*

Figure

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  Fig. 1. Normal findings of lung ultrasound. (A) Characteristic upper-rib, pleural-line, lower-rib landmark that should be identified before starting the exam. (B) Normal lung pattern on M-mode: seashore sign. Motionless chest wall generates horizontal lines and lung sliding makes the sandy pattern below.

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  Fig. 2. Normal findings of lung ultrasound: A-lines. A-lines are horizontal hyperechoic lines parallel to the pleural line and are basic artifacts of a normally aerated lung.

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  Fig. 3. B-lines. B-lines are hyperechoic vertical lines that arise from pleural lines extending to the bottom of the screen without fading and moving synchronously with lung sliding.

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  Fig. 4. Sonographic appearance of lung consolidation. Consolidation is sonographically observed as an area of tissue density. Within the consolidation, hyperechoic foci might be seen that represent air bronchograms.

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  Fig. 5. Pneumothorax on M-mode: stratosphere sign. Below the pleural line, the normal sandy pattern is replaced by horizontal lines showing the absence of lung sliding.

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  Fig. 6. Sonographic appearance of pleural effusion. Fibrin strands are seen floating inside anechoic pleural effusions suggestive of exudative pleural effusion.

Reference

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