Emergency Ultrasound in Trauma

1
Emergency Ultrasound in Trauma

• Anthony J Weekes MD, RDMS
• Janet G. Alteveer, MD
• Sarah Stahmer, MD

2
Clinical Case

• GR is a 62 y male who hit his right torso when he
  slipped on an icy sidewalk. He denies head
  trauma, and can walk without a limp. Two hours
  later the pain in his lower chest has increased
  he comes to the ED.

3
Clinical Case

• PE BP116/72, pulse109, RR 24.
• There is a minor abrasion to right lateral chest,
  which is tender to palpation. Diffuse mild
  abdominal tenderness.
• Meds Coumadin for irregular heartbeat

4
Clinical Case

• 2 large IVs placed, CXR done. Blood tests sent.
• Bedside ultrasound done.
• CXR revealed lower rib fractures, no HTX or PTX

5
Clinical Case

• FFP ordered and OR notified.
• He is found to have a liver laceration and 500 cc
  of blood in the peritoneal cavity.

6
Diagnostic Modalities in Blunt Abdominal Trauma

• Diagnostic Peritoneal Lavage (DPL)
• CAT Scan
• Ultrasound (FAST exam)

7
Diagnostic Peritoneal Lavage

• Advantages
• Very sensitive for identifying intra-peritoneal
  blood
• 106 RBC/mm3 approx. 20 ml blood in 1L lavage
  fluid
• Can be done at the bedside
• Can be done in 10-15 minutes

• Disadvantages
• Overly sensitive, may result in too high a
  laparotomy rate
• Invasive
• Difficult in pregnancy, or with many prior
  surgeries
• Can not be repeated

8
CT Scan

• Advantages
• Identifies specific injuries
• Good for hollow viscus and retroperitoneal injury
• High sensitivity and specificity

• Disadvantages
• Expensive equipment
• 30-60 minutes to complete study
• Only for stable patients
• Not for pregnant patients

9

Focused Abdominal Sonography in Trauma

• FAST

10
FAST

• Advantages
• Can be performed in 5 minutes at the bedside
• Non-invasive
• Repeat exams
• Sensitivity and specificity for free fluid equal
  to DPL and CT

• Disadvantages
• Operator dependent
• May not identify specific injury
• Poor for hollow viscus or retroperitoneal injury
• Obesity, subcutaneous air may interfere with exam

11
FAST Principles

• Detects free intraperitoneal fluid
• Blood/fluid pools in dependent areas
• Pelvis
• Most dependent
• Hepatorenal fossa
• Most dependent area in supramesocolic region

12
FAST Principles

• Pelvis and Supra-mesocolic areas communicate
• Phrenicolic ligament prevents flow
• Liver/spleen injury
• Represents 2/3 of cases of blunt abdominal trauma

13
FAST- principles

• Intraperitoneal fluid may be
• Blood
• Preexisting ascites
• Urine
• Intestinal contents

14
FAST limitations

• US relatively insensitive for detecting traumatic
  abdominal organ injury
• Fluid may pool at variable rates
• Minimum volume for US detection
• Multiple views at multiple sites
• Serial exams repeat exam if there is a change in
  clinical picture
• Operator dependent

15
Evidence supporting use of FAST

• Multiple studies in USA by EM and trauma surgeons
• Studies from Europe and Japan
• Policy statements by specialty organizations

16

• Emergency department ultrasound in the
  evaluation of blunt abdominal trauma.
• Jehle, D., et al, Am J Emerg Med, 1993
• Single view of Morisons pouch in 44 patients
• Performed by physicians after 2 weeks training
• US compared to DPL and laparotomy
• Sensitivity 81.8
• Specificity 93.9

17
Trauma surgical study

• A prospective study of surgeon-performed
  ultrasound as the primary adjuvant modality of
  injured patient assessment. 1994 Rozycki et al.
• N358 patients
• Outcomes used US detection of hemoperitoneum/peri
  cardial effusion

18
Results

• 53/358 (15) patients w/ free fluid on gold
  standard
• All patients Sens 81.5, spec 99.7
• Blunt trauma Sens 78.6, spec 100
• PPV 98.1, NPV 96.2
• Overall accuracy was 96.5 for detection of
  hemoperitoneum or pericardium

19
Trauma Study

• Rozycki G, et al 1998 Surgeon-performed
  ultrasound for the assessment of truncal
  injuries. Lessons learned from 1540 patients
• FAST exam on patients with precordial or
  transthoracic wounds or blunt abdominal trauma

20

• Protocol
• Pericardial fluid OR
• Stable CT
• IP fluid
• Unstable OR
• Results
• N 1540 pts, 80/1540 (5) with FF
• Overall Sens 83.3, Spec 99.7
• PPV 95, NPV 99
• Precordial/Transthor Sens 100, Spec 99.3
• Hypotensive BAT Sens 100, Spec 100

21
FAST Specialty Societies

• Established clinical role in Europe, Australia,
  Japan, Israel
• German Surgical Society requires candidates
  proficiency in ultrasound
• United States
• US in ATLS
• US policies by frontline specialties
• American College of Surgeons
• ACEP,SAEM AAEM

22
FAST

• Perform during
• Resuscitation
• Physical exam
• Stabilization

23
Equipment

• Curved array
• Various footprints
• Small footprint for thorax
• Large for abdomen
• Variable frequencies
• 5.0 MHz thin, child
• 3.5 MHz versatile
• 2.0 MHz cardiac, large pts

24
Time to Complete Scan

• Each view 30-60 seconds
• Number of views dependent on clinical question
  and findings on initial views
• Total exam time usually lt 3-5 minutes
• 1988 Armenian earthquake
• 400 trauma US scans in 72 hrs

25
Focused Abdominal Sonography for Trauma (FAST)

• Consists of 4 views
• Subxiphoid
• Right Upper Quadrant
• Left Upper Quadrant
• Pouch of Douglas

26
FAST

• Increased sensitivity with increased number of
  views
• Will identify pleural effusions
• Reliably detects as little as 50-100cc in the
  thorax
• Sensitivity gt96, specificity 99-100

27
Clinical experience with FAST

• Intraperitoneal fluid
• Sensitivity 82-98, specificity 88-100
• Morisons pouch alone 36-82 sensitivity
• Increased sensitivity with
• Increasing number of views
• Trendelenberg
• Serial examinations
• Can detect as little as 250cc of free fluid

28
Clinical Experience

• Solid organ disruption
• 40 sensitivity for all organs
• 33-94 for splenic injury
• Hollow viscus injury
• Sensitivity 57
• Retroperitoneal injury
• Sensitivity for identification of hemorrhage lt60
  

29
RUQ

• Probe at right thoraco-abdominal junction
• Liver large acoustic window
• Probe marker cephalad
• Rib interference?
• Rotate 30 counterclockwise

30
Scan Plane

• Same image if probe positioned
• Anterior
• Mid axillary
• Posterior

31
RUQ

• Image on screen
• Liver cephalad
• Kidney inferiorly
• Morisons Pouch space between Glissons capsule
  and Gerotas fascia

32
Normal RUQ

• Image kidney
• Longitudinally
• Transversely
• Two toned structure
• Cortex/medulla
• Renal sinus

33
Appearance of blood

• Fresh blood
• Anechoic (black)
• Coagulating blood
• First hypoechoic
• Later hyperechoic

34
Normal Morisons Pouch
Free fluid in Morisons Pouch
35
(No Transcript)
36
(No Transcript)
37
(No Transcript)
38
(No Transcript)
39
(No Transcript)
40
(No Transcript)
41

• Branney, S.W. et al Quantitative sensitivity of
  ultrasound in detecting free intraperitoneal
  fluid J Trauma1995 39
• Peritoneal lavage fluid infused in 100 patients
• Simultaneous scan of Morisons pouch
• By physicians ( Surgery,EM, Radiology)
• Blinded to volume and rate of infusion
• Mean volume of detection 619cc
• Sensitivity at 1 liter 97
• 10 physicians detected less than 400cc

42

Volume Assessment by US

• Caveat to Branney study
• Artificial condition infused fluid
• Fluid in Morisons after pelvis overflow
• Tiling et al
• 200 -250ml detected by US
• Collection gt0.5cm suggests over 500ml
• Transvaginal/rectal
• 15ml of free intraperitoneal fluid

43
Detection of Fluid by Ultrasound

• Affected by positioning
• Location of bleed
• Rate of bleeding
• Operator Experience

• Value of sensitivity of Ultrasound
• Detects clinically injuries
• Non-detection of fluid
• May indicate self- limited bleeding

44
All Fluid is not Blood

• Ascites
• Ruptured Ovarian Cyst
• Lavage fluid
• Urine from ruptured bladder

45
Mimics of Fluid in RUQ

• Perinephric fat
• May be hypoechoic like blood
• Usually evenly layered along kidney
• If in doubt, compare to left kidney
• Abdominal inflammation
• Widened extra-renal space
• Echogenicity of kidney becomes more like the
  liver parenchyma

46
Pitfalls

• RUQ
• Not attempting multiple probe placements
• Not placing the probe cephalad enough to use the
  acoustic window of the liver
• Scanning too soon before enough blood has
  accumulated
• Not repeating the scan

47
LUQ

• Probe at left posterior axillary line
• Near ribs 9 and 10
• Angle probe obliquely (avoid ribs)

48
LUQ Scan Plane

• More difficult
• Acoustic window (spleen) is smaller than liver
• Mild inspiration will optimize image
• Bowel interference is common

49
LUQ Scan

spleen

kidney


Splenorenal fossa a potential space
50
Normal Spleno-renal view
Free fluid around spleen
51
(No Transcript)
52
(No Transcript)
53
(No Transcript)
54
(No Transcript)
55
(No Transcript)
56
To Evaluate the Thorax

• Move probe
• cephalad
• longitudinal
• Image

Liver
Diaphragm
Pleural space
57
Hemothorax
liver
diaphragm
fluid
58
Small Pleural Effusion
Large Pleural Effusion
59

• Ma O John, Mateer J, Trauma Ultrasound
  Examination Versus Chest Radiography in the
  Detection of Hemothorax
• Ann Emerg Med March 1997
• 240 trauma US study patients
• 26 had hemothorax ( CT or chest tube)
• CXR and US
• 0 false positive
• 1 false negative
• 25 true positive
• 214 true negative

60
Pelvic View

• Probe should be placed in the suprapubic position
• Either can be transverse or longitudinal
• Helpful to image before placement of a Foley
  catheter

61
Pelvis (Long View)
62
Pelvis Transverse
63
Normal Transverse pelvic
Fluid in pelvis
64
Pelvic View Sagittal
clot
bladder

• Fluid in front of the bladder
• If bladder is empty or Foley already placed
• Trick of trade
• IV bag on abdomen
• Scan through bag

65
Blood in the Pelvis
66
(No Transcript)
67
(No Transcript)
68
Free fluid in the pelvis
69
FAST Algorithm
 
70
Ultrasound in the Detection of Injury From Blunt
or Penetrating Thoracic
Trauma
71
Penetrating Thoracic Injury

• Clinical challenge
• Where is the penetration?
• What was the weapon?
• What was the trajectory?
• What organ(s) have been injured?
• Improved outcomes in patients with normal or
  near-normal vital signs

72
Penetrating Cardiac Trauma

• Pericardial effusion
• May develop suddenly or surreptitiously
• May exist before clinical signs develop
• Salvage rates better if detected before
  hypotension develops

73
Clinical Case

• QD is 37 year old male brought in by EMS for
  ingesting entire bottle of unidentified red and
  white pills. In the ambulance bay he pulls out a
  knife and stabs himself in the left nipple.

74
Clinical Case

• Initial BP 116/72, pulse 109 RR 24. IVs placed.
• No JVD, Clear breath sounds, non tender abdomen
• As CXR is about to be done, pulse increases to
  134.
• Bedside ultrasound is done while cartridge is
  developed.

75
Clinical Case
76
Clinical Case

• Patient is taken to the OR
• Penetrating cardiac wound is repaired

77
Subcostal View

• Most practical in trauma setting
• Away from airway and neck/chest procedures
• Also called Sub-Xyphoid view

78
Subcostal View
79
Subcostal View
80
Pericardial Fluid
fluid
81
(No Transcript)
82
(No Transcript)
83
(No Transcript)
84
(No Transcript)
85
(No Transcript)
86
Occult Penetrating Cardiac Trauma

• Observation unreliable
• Subxiphoid window
• Invasive
• 100 sensitive, 92 specific
• Negative exploration rates (as high as 80)
• Ultrasound reliable indicator of even small
  pericardial effusion

87
Trauma Study

• The role of ultrasound in patients with
  possible penetrating cardiac wounds a
  prospective multicenter study.
• Rozycki GS J Trauma. 1999
• Pericardial scans performed in 261 patients
• Sensitivity 100, specificity 96.9
• PPV 81 NPV100
• Time interval BUS to OR 12.1 /- 5.9 min

88
Avoid Pitfalls

• Normal echo does not definitively rule out major
  pericardial injury
• Repeat echo with ? clinical picture
• Epicardial fat pad may easily be misinterpreted
  as clot
• Hemothorax may be confused with pericardial
  effusion

89
Blunt Cardiac Trauma

• Basic Assessments
• Pericardial effusion
• Assess for wall motion abnormality
• RV
• closest to anterior chest wall
• Most likely to be injured

• Advanced Assessments
• Assess thoracic aorta may need TEE to see all
  of thoracic aorta
• Hematoma
• Intimal flap
• Abnormal contour
• Valvular dysfunction or septal rupture

90
Blunt cardiac trauma

• Injuries difficult to assess by FAST
• Valvular incompetence
• Myocardial rupture
• Intracardiac thrombosis
• Ventricular aneurysm
• Coronary Thrombosis
• Intra-cardiac Thrombosis

91

• The most important preoperative objective in
  the management of the patient with trauma is to
  ascertain whether or not laparotomy is needed,
  and not the diagnosis of a specific organ injury