Prospective Evaluation of Safe Observation Period after Asymptomatic Penetrating Thoracic Injury: 1 Hour is Enough

Introduction: The observation period was recently challenged by some studies; and it has been suggested that a 1-hour observation period may be sufficient to allow safe discharge in asymptomatic patients with penetrating thoracic injury (PTI) and normal initial Chest X-Ray (CXR). Objective: The current study was performed to investigate if in asymptomatic and hemodynamically stable patients with PTIs who has an initial normal evaluation, 1-hour observation interval is safe to detect clinically significant injuries and is it possible to discharge these patients safely after a negative Extended – Focused Assessment with Sonography in Trauma (E-FAST) at hour1 instead of hour 3. Method: This cross-sectional study was performed on asymptomatic patients with penetrating thoracic injury, referred to emergency department (ED) and normal initial CXR and the Extended Focused Assessment with Sonography in Trauma (E-FAST). The second E-FAST was done 1 hour after the first one and the third repeat E-FAST and control CXR then performed 3 hours post-injury. 24 hours follow up by phone call was done for each patient after discharge. Results: Finally, 117 patients with the average ages of 25.9 ± 7.8 years were enrolled of whom 92.5% were male. Eight patients developed PTX or HTX during first hour of observation that were diagnosed by E-FAST or CT scan requested by the in-charge physician. One hundred-nine patient completed E-FAST and radiograph studies at times zero, 1 h, and 3 h. One patient had a normal initial evaluation but demonstrated a PTX on the 3-h managed without intervention. The rate of delayed abnormality after an initially normal study was 7.7 % (9/117). No discharged patients returned to our ED with delayed manifestations of either PTX or HTX. Conclusion: The results of our study have shown that asymptomatic patients with PTI with negative initial evaluation and no deterioration at intervals, about 1 hour may be sufficient for detection of clinically significant pathology, considered for safe and early discharge.