Lung ultrasoundin the critically ill patient
BASICS
Rohit Patel, MDUniversity of Florida Health
Director, Critical Care Ultrasound Surgical ICUCenter for Intensive Care
Gainesville, Florida
Sunday, August 14, 16
IntroductionLearning ObjectivesIdentify and interpret ‘signs’ found in lung ultrasoundBe able to identify presence or absence of ‘lung sliding’Use ‘signs‘ found in lung ultrasound to evaluate respiratory failure in algorithm
Overlooked?Basic terminology -- was a free field, made sure no terms were used elsewhere
Sunday, August 14, 16
Critical Care UltrasoundA lines Bat sign B lines
B3 lines B7 lines BLUE protocol
BLUE points Comet tails Sinusoid sign
Jellyfish sign Lung point Merlin's space
PLAPS Point Quad sign Seashore sign
Shred sign Stratosphere sign
Tissue like sign Z lines
Sunday, August 14, 16
What can I find?
Pneumothorax
Hemothorax
Other pleural effusions
Alveolar consolidation
Pulmonary edema and/or extravascular lung water
Pulmonary embolism?
Sunday, August 14, 16
What are the questions?
Focused assessment with sonography in trauma
Focused abdominal sonography in trauma
Shock, hypoxia, oligoanuria, fever, etc.?
Sunday, August 14, 16
Principles of lung ultrasoundA simple, 2-d apparatus is the most appropriate
Most sophisticated are for cardiac, usually big, image resolution, start up time, probe shape, high cost all hinders
Sunday, August 14, 16
Principles of lung ultrasoundThe lung is the largest organ in the body
17% of body skin projection
Where to apply the probe? Same place as stethoscope?
BLUE points: similar to ECG or partitions of abdomen
Sunday, August 14, 16
Principles of lung ultrasoundAnterior zone = "BLUE hands"
Lateral zone
Posterior zone
Lichtenstein. Textbook. Whole body ultrasonography in the critically ill.Sunday, August 14, 16
Upper BLUE point: between third and fourth finger of BLUE hand, at palmar insertion
Lower BLUE point: middle of palm of lower BLUE hand; allows for avoidance of heart in most cases
Phrenic line: continuation of this line locates the lateral place
PLAPS point: "posterior and/or lateral alveolar and/or pleural syndrome" -- intersection between the posterior axillary line and the transversal line continuing posteriorly to the lower BLUE point; also can have extended PLAPS points
Sunday, August 14, 16
Principles of lung ultrasoundStage 1: anterior wall
Stage 2: adds lateral wall from anterior to posterior axillary line
Stage 3: external part of the posterior wall; aim from back towards sky; no visual control of probe so need to hold with whole hand; can depress bed if need to
Stage 4: patients must be positioned laterally or sitting; can also study the apex
Sunday, August 14, 16
Principles of lung ultrasoundUpper and Lower BLUE points
Phrenic point
PLAPS point
Lichtenstein. Textbook. Whole body ultrasonography in the critically ill.Sunday, August 14, 16
How to hold the probeLike a fountain pen
Decreases fatigue
Minimizes pressure placed (important for vascular structures and optic nerve)
Operators hand must remain still especially with dynamic evaluations
Don't hold the probe too tight --> can fatigue you (another person should be able to withdraw it from your grip)
May confuse when evaluating lung artifacts with your own movement if not stable
Sunday, August 14, 16
Sunday, August 14, 16
Principles of lung ultrasoundAll signs arise from the pleural line
Rib shadows
A line
Pleural line
This pattern: bat sign
Sunday, August 14, 16
Principles of lung ultrasoundThe pleural line indicates the interface between the soft tissues (rich in water) and lung tissue (rich in air); parietal pleura in all cases and visceral pleura only when no pneumothorax
Lung sliding indicates inspiratory descent of the visceral pleura against the parietal pleura, and the expiratory ascent
Observation of the pleural line shows this to and fro dynamic (glittering, shimmering, sparkling, twinkling)
Better seen with longitudinal scans and hand must be motionless; M mode useful for data recording
Sunday, August 14, 16
Principles of lung ultrasound
The main normal artifact: the A lineRepetition of the pleural line, roughly horizontal hyperechoic from the pleural line
Comes from air blocking the ultrasound beam
Distance between the pleural line and A line is equal to the skin-pleural line difference
Sunday, August 14, 16
Sunday, August 14, 16
Sunday, August 14, 16
A line
Sunday, August 14, 16
A line
Sunday, August 14, 16
Sunday, August 14, 16
Principles of lung ultrasound
B lines arise from fluid air artifacts and give hyperechoic patterns and up to a completely diffuse white pattern called Birolleau variant
Conclude that fluids traditionally described as anechoic make hyperechoic tones when small and surrounded by air
Sunday, August 14, 16
Principles of lung ultrasoundB line B7 lines B3 lines
Birolleau Variant
Sunday, August 14, 16
Principles of lung ultrasoundB line video
Sunday, August 14, 16
Principles of lung ultrasoundB line video
Sunday, August 14, 16
Sunday, August 14, 16
Sunday, August 14, 16
Sunday, August 14, 16
IntroductionLearning ObjectivesIdentify and interpret ‘signs’ found in lung ultrasoundBe able to identify presence or absence of ‘lung sliding’Use ‘signs‘ found in lung ultrasound to evaluate respiratory failure in algorithm
Overlooked?Basic terminology -- was a free field, made sure no terms were used elsewhere
Sunday, August 14, 16