Basics of eFAST for surgeons

1. eFAST (Extended Focused
Assessment with Sonography in
Trauma)
Dr P Maruthapandian, MS.,
Asst Professor,
Institute of General Surgery,
MMC&RGGGH.

2. eFAST
● Part of primary survey in unstable patients in trauma even in Tertiary centre
● can be performed at the same time as resuscitation.
Rapid Reproducible
Portable Non invasive

3. FAST eFAST
Focused Assessment
with Sonogram in Trauma
Extended Focused
Assessment with
Sonogram in Trauma
4 Windows 6 Windows
RUQ/LUQ/SUPRAPUBI
C VIEW/SUB XIPHOID
VIEW
RUQ/LUQ/SUPRAPUBIC
VIEW/SUB XIPHOID
VIEW + 2 THORACIC
WINDOW

4. BASIC PHYSICS: THE PIEZOELECTRIC EFFECT
The ultrasound image that we are accustomed to viewing is a complex image created by
sound waves. Ultrasound technology converts this sound energy into an electrical
energy in order to display an image for interpretation. This process of energy conversion
between electrical and acoustic energy is known as the piezoelectric effect.

5. ● Sound is an oscillation of mechanical waves of compression and
decompression through a medium (i.e., tissue).
● Frequency is the number of times per second the sound wave is repeated, and
is measured in cycles/second, or Hz.
● We can hear frequencies ranging from 20 to 20,000 Hz.
● Medical ultrasound imaging utilizes frequencies much higher than what the
human ear can hear, between 2 and 20 million cycles per second (MHz).

6. As a sound wave moves through a medium, some of the energy is lost or
transformed into other forms of energy. This is referred to as attenuation.
Fluid, such as water or saline, will have nearly no attenuation.
Attenuation Tissue
density

7. Probes
● The ultrasound transducer (probe) converts between
electrical and acoustic energies by the use of specialized
“piezoelectric” crystals.
● The transducer converts electrical energy into acoustic
energy for transmission through a medium, such as saline
or gel.
● The transducer then “listens” for returning (“reflected”)
sound waves and captures the reflected echoes and
converts them back into electrical energy.
● Once the acoustic energy is captured and converted into
electrical energy by the transducer, electrical voltages are
then transmitted to the ultrasound monitor where images
are formed (pulse-echo technique).

9. Ultrasound terminology
● Ultrasound characteristics of tissue are described in terms of “echogenicity.”
● Echogenicity refers to the brightness of the tumor, organ, or tissue that is
being described.
● Aechoic -devoid of acoustic wave reflection and appears black
● hyperechoic -tissue that is brighter,
● hypoechoic is less bright, and
● isoechoic is the same brightness as compared to the reference tissue (e.g.,
liver or spleen).
● Echogenicity is determined by the character of the tissue (i.e., medium)
where the velocity of the acoustic waves are determined

10. Indications for eFAST
● Blunt &penetrating cardiac trauma
● Blunt abdominal trauma
● Blunt & penetrating chest trauma

11. Limitations of eFAST
● Will not reliably detect less than 100 mL of free blood
● Does not directly identify injury to hollow viscus
● Cannot reliably exclude injury in penetrating trauma
● May need repeating or supplementing with other investigations
● Is unreliable for assessment of the retroperitoneum

12. LOOKING FOR….?
Intraperitoneal
hemorrhage
Pneumothorax
Haemothorax
Traumatic Pericardial
effusion

13. EFAST-How it is performed?
CARDIAC:
Pericardial (usually
subcostal)
ABDOMINAL:
● Perihepatic/RUQ
● Perisplenic/LUQ
● Pelvic(long/trans)
THORAX:
● RUQ
● LUQ
● Parasternal
FAST
eFAST

15. RUQ view
● Probe in longitudinal
● Lower ribs of Rt
chest wall
● Midaxillary line slide
posteriorly
● Morrisons pouch
● Sub diaphragmatic
space
● Rt costophrenic
angle

16. RUQ view

17. RUQ view

18. RUQ View-Rt pleural cavity

20. Free fluid in inf pole of kidney

21. Free fluid in pleural cavity

23. Clotted blood may be hypoechoic …not anechoic

24. LUQ VIEW

26. LUQ view
● Longitudinal probe
● Mid to posterior axillary
line
● Leino renal space
● Perisplenic
● Left Costco phrenic angle

28. FF IN LEFT SUBDIAPHRAMATIC AREA

29. Beware…!

30. SUPRAPUBIC VIEW

32. Suprapubic view
● Just above pubic
symphysis
● Transverse &
longitudinal probe
● Female vs Male

33. Transverse view
Longitudinal view

34. Normal suprapubic view

35. FF in posterior to the
bladder in longitudinal
view

39. PERICARDIAL VIEW

41. Sub xiphoid view
● Left subcostal
probe position
● Angled under
rib cage,
towards left
shoulder

43. Pericardial effusion

44. Pneumothorax in eFAST

45. ● Most anterior chest
spaces in supine patients
● Parasternal/ longitudinal

47. Beware of false positive absent lung sliding…
● Atelectasis
● Lung &pleura adhering together
● Phrenic nerve palsy
● Pulmonary fibrosis
● Cardiopulmonary arrest
● Poor operator skills
● Large infiltrates &pleural effusion

48. SENSITIVITY OF eFAST
Sensitivity Specificity
Intraperitoneal fluid 73-88% 98-100%
Hemothorax 96.2% 100%
Pneumothorax 92-98% 99.4%

49. Thank you 😎