FAST Exam DR. WASEEM AHMED ABUJAMEA ED CONSLTUNT PROGRAM DIRECTOR,KSMC

FAST Exam Introduction Introduction Ultrasound Physics Ultrasound Physics Technique Technique Indications for FAST exam Indications for FAST exam Performing a FAST exam Performing a FAST exam Limitations Limitations Questions Questions

What is the FAST exam? Focused Assessment by Sonography in Trauma Focused Assessment by Sonography in Trauma Focused exam using ultrasound to diagnose hemorrhage in a trauma setting Focused exam using ultrasound to diagnose hemorrhage in a trauma setting Ideally takes < 3 min Ideally takes < 3 min 4 primary views 4 primary views RUQ RUQ LUQ LUQ Subxiphoid Subxiphoid Suprapubic Suprapubic

Basic Ultrasound Physics Ultrasound is a spectrum of sound frequencies above the human hearing range. Ultrasound is a spectrum of sound frequencies above the human hearing range. Molecules must be present for sound to exist. Molecules must be present for sound to exist. Every object has an echogenicity. When sound waves hit the object some are transmitted through and some bounce back. Every object has an echogenicity. When sound waves hit the object some are transmitted through and some bounce back. Every substance will respond differently to the sound waves striking it’s surface. This occurs at every sound-to-sound interface and the reflection of sound waves can be used to create and image. Every substance will respond differently to the sound waves striking it’s surface. This occurs at every sound-to-sound interface and the reflection of sound waves can be used to create and image.

Technique Goal: to identify blood in body cavities where it is not supposed to be Goal: to identify blood in body cavities where it is not supposed to be Unclotted blood appears black on US Unclotted blood appears black on US Clotted blood appears gray Clotted blood appears gray Abdominal probe with small footprint (between 1- 3 cm) with range of frequency between 2.0 Hz and 5.0 Hz Abdominal probe with small footprint (between 1- 3 cm) with range of frequency between 2.0 Hz and 5.0 Hz Scan 4 areas Scan 4 areas RUQ RUQ Subxiphoid Subxiphoid LUQ LUQ Suprapubic Suprapubic

Indications Blunt thoracoabdominal trauma Blunt thoracoabdominal trauma Penetrating thoracoabdominal trauma Penetrating thoracoabdominal trauma Suspected pericardial tamponade Suspected pericardial tamponade Trauma patient with hypotension on unknown etiology Trauma patient with hypotension on unknown etiology Thoracoabdominal trauma in a pregnant patient Thoracoabdominal trauma in a pregnant patient

Right Upper Quadrant Sagittal view obtained by placing probe either in the midclavicular line on the lower rib cage or below the right costal margin Sagittal view obtained by placing probe either in the midclavicular line on the lower rib cage or below the right costal margin May have to move probe laterally to avoid gas in hepatic flexure May have to move probe laterally to avoid gas in hepatic flexure Air-filled lung creates reflection artifact in which lung appears to be composed of liver parenchyma Air-filled lung creates reflection artifact in which lung appears to be composed of liver parenchyma Scan for black fluid in potential spaces Scan for black fluid in potential spaces

Normal RUQ

Abnormal RUQ

Subxiphoid Probe placed under xiphoid almost parallel with skin surface directed towards patient’s left shoulder Probe placed under xiphoid almost parallel with skin surface directed towards patient’s left shoulder Parasternal view may be used when supxiphoid unable to be obtained Parasternal view may be used when supxiphoid unable to be obtained Consider pnuemothorax when unable to obtain images of heart and no apparent reason Consider pnuemothorax when unable to obtain images of heart and no apparent reason

Normal Subxiphoid

Abnormal Subxiphoid

Left Upper Quadrant Most technically difficult to obtain Most technically difficult to obtain Probe placed parallel with ribs in posterior axillary line Probe placed parallel with ribs in posterior axillary line Scan potential spaces between diaphragm and spleen and spleen and kidney for free fluid Scan potential spaces between diaphragm and spleen and spleen and kidney for free fluid

Normal LUQ

Abnormal LUQ

Suprapubic Entire pelvis should be scanned from top to bottom with transducer in transverse place and them side to side with transducer in sagittal plane Entire pelvis should be scanned from top to bottom with transducer in transverse place and them side to side with transducer in sagittal plane Pouch of Douglas is the most dependent site in peritoneal cavity Pouch of Douglas is the most dependent site in peritoneal cavity First sign of blood is often two small black triangles on either side of rectum First sign of blood is often two small black triangles on either side of rectum “Bow tie sign”

Normal Suprapubic

Abnormal Suprapubic

Limitations Retroperitoneal bleeding Retroperitoneal bleeding Inadequate volume of fluid Inadequate volume of fluid Not enough time elapsed since trauma to demonstrate bleeding Not enough time elapsed since trauma to demonstrate bleeding Solid organ trauma with encapsulated bleeding Solid organ trauma with encapsulated bleeding Image quality dependent on quality of US machine and probe, body habitus of patient, physical injuries Image quality dependent on quality of US machine and probe, body habitus of patient, physical injuries Scan and interpretation are operator dependent Scan and interpretation are operator dependent

Questions?