BACKGROUND:  Focused Abdominal Sonography for Trauma (FAST) is a most commonly used in the initial management of Blunt Abdominal Trauma (BAT) patients, Being  non invasive, repeatable and without risk of irradiation, make it attractive tool in evaluation of trauma patients in every hospital setup.

OBJECTIVE:  Evaluation of FAST sensitivity and specificity in detection of hemoperitoneum(free fluids) in blunt abdominal trauma patients.

METHODS:  A Prospective randomized study was conducted in Smt SCL General Hospital on 150 patients who presented with BAT and underwent FAST scan. The presence of intra–peritoneal free fluid was interpreted as positive.

RESULTS:  A 150 patients included in the study, the sensitivity of FAST was 84 % and specificity was 97.6% in blunt abdominal trauma.

 CONCLUSION:  FAST is highly sensitive and specific in detection of hemoperitoneum after blunt abdominal trauma.  Its high specificity make it suitable as "rule in" test in blunt abdominal injury. In unstable patients FAST may help in triaging and identifying those requiring laparotomy. Negative FAST scans do not exclude abdominal injury.