FAST looks primarily for free fluid in the pericardial, right upper quadrant, left upper quadrant, and pelvic windows. eFAST extends the protocol to include pleural assessment for haemothorax and pneumothorax.
The FAST concept is inherently point-of-care and lends itself well to portable devices. The core strengths are speed, repeatability, and the ability to support decision-making without transporting an unstable patient away from resuscitation.
FAST and eFAST are not designed to quantify total blood loss or comprehensively define organ injury. In unstable patients, a positive study may accelerate operative or procedural decision-making. In stable patients, CT remains the more comprehensive modality.
False negatives and false positives still matter. Small fluid volumes, operator inexperience, body habitus, and timing relative to injury can all affect findings. The clinician should integrate FAST findings with haemodynamics, mechanism, and the broader trauma picture.
Handheld ultrasound fits naturally into FAST and eFAST workflows because these protocols are designed for focused, bedside, time-sensitive decisions. Their value comes from disciplined use, not from trying to turn a targeted trauma tool into a complete imaging study.
Dr Yahya Docrat is an anaesthetist based in Johannesburg, South Africa, with clinical experience in perioperative medicine and point-of-care ultrasound applications in anaesthesia, emergency medicine and critical care.