First author and reference no.
Year
Modality
n
Sensitivity
Specificity
Accuracy
Diagnostic reference standard
Boulanger [1]
1996
FAST
400
81
97
94
DPL, CT
Brown [10]
2001
FAST
2,693
84
96
96
DPL, CT, laparotomy, autopsy
Kirkpatrick [6]
2005
HHFAST
313
68.6
96.9
91.6
CT, laparotomy
Walcher [9]
2006
p-FAST
202
93
99
99
CT, laparotomy
Busch [11]
2006
PHASE
38
90
96
FAST, CT
p-FAST can lead to relevant changes in prehospital trauma therapy and management with the aim to shorten the time to surgical therapy (Table 7.2). The patients receive p-FAST on average 35 ± 13 min prior to inhospital FAST or CT scan [9]. Early diagnosis is precious as it can contribute to accelerate and optimize patient care and orientation.
Modification in therapy (21 %) and management on scene (30 %) |
Changes in selection of trauma center (22 %) |
Information transfer about prehospital findings to trauma team (52 %) |
Changes in trauma team preparation and management (92 %) |
Ultrasound on scene 35 min prior to FAST in the emergency department |
Detection of hemoperitoneum at the trauma scene means that the receiving hospital can be notified in advance and the inhospital trauma team can modify their preparations by expanding their team to include a surgeon and prepare theater for urgent laparotomy for hemorrhage control. Based on the p-FAST results, the admitting trauma center might be changed toward the closest appropriate hospital, especially in rural settings, where mean response times and mean transport times can be much longer.
7.3 Training
US is the first and foremost an operator-dependant examination. Thus, experience plays an important role, and sensitivity drops with little experience. A standardized training with both theoretical and hands-on modules is mandatory to gain the required skills to conduct FAST or p-FAST sufficiently. This training should include subjects with positive findings.
Emergency physicians/paramedics treating patients at the scene of an accident face several challenges such as time pressure. This has important implications for the training program. Thus, the training program should include real-time simulation training and different patient positions (e.g., ventral position), where the learner has to find the appropriate time frame to integrate p-FAST into the prehospital trauma care algorithm, adopt the transducers’ position, and furthermore face the time pressure. After a 1-day course with hands-on training as described above, p-FAST can be performed by both paramedics and physicians who were not familiar with the technique before attending the course with a high sensitivity, specificity, and accuracy [13]. However, to maintain this skill at the required competence level, regular practice is necessary.