Positive FAST without hemoperitoneum due to fluid resuscitation in blunt trauma

Focused Assessment with Sonography for Trauma (FAST)

The main cause of death in traumas is hypovolemic shock. Physical examination is limited to detect hemopericardium, hemoperitoneum, and hemopneumothorax. Computed tomography (CT) is the gold standard for traumatic injury evaluation. However, CT is not always available, is more expensive, and there are transportation issues, especially in hemodynamically unstable patients. In this scenario, a rapid, reproducible, portable, and noninvasive method such as ultrasound emerged, directed for detecting hemopericardium, hemoperitoneum, and hemopneumothorax, in a "point of care" modality, known as the focused assessment with sonography for trauma (FAST) protocol. With decades of experience, spread worldwide, and recommended by the most prestigious trauma care guidelines, FAST is a bedside ultrasound to be performed when accessing circulation issues of trauma patients. It is indicated to hemodynamically unstable patients with blunt abdominal trauma, with penetrating trauma of the thoracoabdominal transition (where there is doubt of penetrating the abdominal cavity) and for any patient with the cause of the instability unknown. There are four regions to be examined in the traditional FAST protocol: pericardium (to detect cardiac tamponade), right upper abdominal quadrant, left upper abdominal quadrant, and pelvis (to detect hemoperitoneum). The called extended FAST (e-FAST) protocol also searches the pleural spaces for hemothorax and pneumothorax. It is important to know the false positives and false negatives of the protocol, as well as its limitations. FAST/e-FAST protocol is designed to provide a simple "yes or no" answer regarding the presence of bleeding. It is not intended to quantify the bleeding nor evaluate organ lesions due to its limited accuracy for these purposes. Moreover, the amount of bleeding and/or the identification of organ lesions will not change patient's management: Hemodynamically unstable patients with positive FAST must go to the operating room without delay. CT should be considered for hemodynamically stable patients.

Characteristics of computed tomography in hemodynamically unstable blunt trauma patients: Experience at a tertiary care center

Emergent exploratory laparotomy is recommended for hemodynamically unstable blunt trauma patients suspected of having hemoperitoneum. However, given the unreliability of ultrasonography and rapid scan speed of computed tomography (CT), CT might help clinicians provide accurate information even in hemodynamically unstable trauma patients. This observational study aimed to describe the bleeding site and hospital course of severe blunt trauma patients with hemoperitoneum diagnosed by CT scan.We enrolled all consecutive adult blunt trauma patients (≥18 years old) who underwent whole-body CT before operation between February 2012 and October 2016. Patients with hemoperitoneum on CT images were included and categorized into hemodynamically stable and unstable (persistent hypotension despite fluid resuscitation) groups.Among 1723 severe blunt trauma patients, 136 patients with hemoperitoneum were included. Of these, 98 (72.1%) patients had documented intraperitoneal injury, and the liver (60.2%) was most frequently damaged site, followed by spleen (23.5%) and mesentery (23.5%). The rate of intraperitoneal organ injury did not differ between hemodynamically stable (n = 107) and unstable (n = 29) groups (69.2% vs 82.8%, P = .15), while the documented active internal bleeding was high in the unstable group (29.9% vs 69.0%, P < .001). In the unstable group, 14 (48.3%) patients underwent emergent operation, while 3 patients underwent embolization, and the others were treated in a conservative manner.Even in hemodynamically unstable hemoperitoneum patients, 17.2% had no documented intraperitoneal injury and over half of the patients were treated without emergent operation.