FAST EXAMINATION AS AN IMPORTANT ASSESSMENT IN PATIENTS WITH TRAUMA
(Focused Assessment with Sonography in Trauma)
Authors: Hisham A. Ben Lamin MD. - Chiranjivi Potu MD.
FAST examination is used in emergency Blunt trauma to Abdomen and can be also useful in penetrating injuries to decide either to operate or not for the presence of free fluid. Ultrasound is the ideal initial imaging modality because it can be done at the same time with other resuscitation methods of care and provides to us vital information more than radiography or CT scanning. It is important in the unstable patients to decide whether to perform laparotomy or not. The sole aim of FAST examination is to detect the presence of free intraperitoneal fluid. Many life threatening injuries to abdomen cause internal bleeding and ultrasound can perfectly detect intraperitoneal, pericardial and pelvic bleeding. The FAST test is now more broadened to include the examination of the lungs to exclude the presence of Haemothorax and Pneumothorax in chest trauma and it is referred as EFAST examination (EXTENDED FOCUSED ASSESSMENT WITH SONOGRAPHY IN TRAUMA).
FAST examination is proved by studies to have 90% sensitivity, 99% specificity and 99% accuracy. These results were confirmed by CT scanning and exploratory laparotomy.
FAST abdominal examination will include the following regions:
- Intra-thoracic abdomen: this will include the areas under the rib cage (Spleen, Liver, Stomach and Diaphragm).
- Retro-peritoneal abdomen: will include Kidneys, Ureters, Pancreas, abdominal Aorta and inferior vena cava.
- True abdomen: will include Small & Large Intestine, Gravid uterus and distended urinary bladder.
- Pelvic abdomen: defined by the pelvic bones (urinary bladder, urethra, rectum, small intestine, Ovaries, Fallopian tubes and Uterus).
The attending emergency personnel should perform the following examination within 3 minutes, and this can be done safely and accurately in the Ambulance Helicopters, in the fixed wing planes or in the Ambulance vehicles:
- Pericardial view.
- Peri Hepatic view (Morison’s pouch) between Liver and right Kidney.
- Peri – Splenic area view between Spleen and left Kidney.
- Pelvic view for the posterior bladder area in males and Douglas pouch in females.
- The examination can be extended to chest wall to detect the presence of Haemothorax and/or Pneumothorax (EFAST examination).
FAST examination is done in the Supine position; it should be done by trained medical personnel and should be quick. It does not need a comprehensive examination.
Specific indications of FAST examination:
- Blunt Trauma to Abdomen , Heart and ( Chest =EFAST )
- Penetrating Trauma to Abdomen, Heart and (Chest = EFAST).
- Ectopic Pregnancy detection.
FAST is most useful in the following conditions:
- Patient is in Shock and the cause of hypotension is unknown.
- Patients with penetrating trauma in the upper abdomen and /or lower chest.
- Patients injured with no indications for CT scanning, this patient is to be put on repeated FAST examination.
- Patient with trauma to Abdomen or Chest in a medical facility that has no trauma unit and to be transferred , we can do the following procedures :
- To perform Pericardiocentesis if pericardial is detected by FAST examination.
- Insert a chest tube if we detected by FAST examination a Haemothorax and /or Pneumothorax.
This is important if transfer of patient will be by Aero-Medical transport.
- Unstable patient :
FAST examination result is positive: transfer the patient to theatre for laparotomy.
FAST examination result is negative: consider other sites of blood loss. Repeat FAST examination later on or you can do DPL (Diagnostic Peritoneal Lavage).
- Stable patient :
FAST examination result is positive: refer the patient to CT scanning to locate the cause of hidden bleeding.
FAST examination result is negative: clinical observation, do serial examinations and repeat FAST examination and do CT scanning.
In general, FAST and EFAST examinations can be done in extremely short time by trained medical attendant and will give an accurate results of presence or absence of internal bleeding that occurred post trauma and allow us to make a quick decision to how to save our patients while we are in the scene of accident and trauma or transported or in the emergency unit.
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