The compatibility of Focused Assessment with Sonography in Trauma (FAST) in the supine position vs FAST in the Trendelenburg position in determining free fluid in blunt abdominopelvic trauma patients

Introduction: Focused Assessment with Sonography for Trauma (FAST) is found to be a diagnostic tool initially to detect intra-abdominal fluid in abdominal trauma. This study examined the compatibility of FAST in the supine position vs FAST in the Trendelenburg position in determining of free fluid in blunt abdominopelvic trauma patients. Materials and Methods: This descriptive cross-sectional study was conducted prospectively on all patients with blunt abdominal trauma during ۲۰۱۹-۲۰۲۱ in Shahid Rahnemoon Yazd Teaching Hospital. sampling method was convenient. An emergency medicine specialist did FAST, on the abdominal and pelvic trauma patients, in the supine position. The patients were placed in the Trendelenburg position for ۳ minutes and FAST was performed again. Demographic information and the results obtained from both FAST ultrasounds of the patients were recorded. The sensitivity and Specificity of the supine test, Positive predictive value (PPV), and negative predictive value of the supine (NPV) test were assessed. Results: In this study, in the FAST performed in the supine position free fluid was seen in ۱۳.۴%(n=۱۶) of the patients while in the Trendelenburg position, ۲۹.۴% (n=۳۵) of the patients clearly showed free fluid in the abdomen and pelvis. The overall Sensitivity, Specificity, PPV, and NPV of the supine test were ۳۰.۵۵%, ۹۳.۹۷%, ۶۸.۷۵%, and ۷۵.۷۲% respectively. Conclusion: using the Trendelenburg position, for the detection of free fluid in patients with blunt abdominal trauma and stable hemodynamics with or without abdominal pain, which first-time FAST exam is not reliable or is suspected of free fluid presence, is recommended.

Keywords:

Abdominal Injuries , Focused Assessment with Sonography for Trauma , Supine Position , Head-Down Tilt