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Resuscitation room ultrasound examination
in the resuscitation room is rapidly replacing diagnostic
peritoneal lavage as a means to evaluate the abdomen
in trauma patients. The FAST (Focused Abdmonial Sonography
for Trauma) scan specifically looks only for free
intraperitoneal (and pericardial) fluid using five
areas for ultrasound analysis.
Rozycki GS; Shackford SR 'Ultrasound,
what every trauma surgeon should know' J Trauma 1996
40(1):1-4
'Ultrasonography has been shown
to be as accurate as DPL and CT in the detection of
hemoperitoneum following abdominal trauma.'
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'It is now well established that surgeons
can perform a focused abdominal ultrasound for trauma (FAST)
as accurately as formally trained radiologists. In a collected
series of 4,941 patients, surgeons performed FAST with a
sensitivity of 93.4%, a specificity of 98.7% and an accuracy
of 97.5% in detecting both hemoperitoneum and visceral injury.'
FAST demonstration
videos:
Courtesy Grace Rozycki, MD FACS
Evidence
Boulanger BR; McLellan BA; Brenneman
FD; Ochoa J; Kirkpatrick AW 'Prospective evidence of the
superiority of a sonography-based algorithm in the assessment
of blunt abdominal injury.' J Trauma, 1999 Oct, 47:4, 632-7
BACKGROUND: Although the routine use of
FAST (focused assessment with sonography for trauma) in
the evaluation of trauma victims is increasing, to our knowledge,
a prospective comparison of contemporary adult trauma victims
managed with and without FAST has not been reported in North
America. METHODS: Adult victims of blunt trauma for whom
there was a suspicion of abdominal injury were managed with
one of two diagnostic algorithms, FAST or no-FAST. The two
algorithms were compared for diagnostic accuracy, cost,
time, and delayed diagnoses. RESULTS: Among 706 patients
(mean Injury Severity Score, 23), 460 were managed with
FAST and 246 with no-FAST. The two groups were similar with
respect to age, Injury Severity Score, prehospital time,
and mortality (p = not significant). There were 3 of 460
(0.7%) delayed diagnoses in the FAST group and 4 of 246
(1.6%) in the no-FAST group (p = not significant). The diagnostic
accuracy for the FAST and no-FAST algorithms was 99% and
98%, respectfully. The FAST and no-FAST algorithms led to
similar rates of laparotomy, 13% and 14%, respectfully,
but nonoperative management was more common in the no-FAST
group (p < 0.01). The mean diagnostic cost for the FAST
algorithm was $156, compared with $540 with the no-FAST
algorithm (p < 0.0001) and the mean time required for diagnostic
work-up was 53 minutes with the FAST algorithm, compared
with 151 minutes with the no-FAST algorithm (p < 0.0001).
CONCLUSION: This study has provided prospective evidence
that a FAST-based algorithm for blunt abdominal injury was
more rapid, less expensive, and as accurate as an algorithm
that used computed tomography or diagnostic peritoneal lavage
only. Trauma centers are encouraged to incorporate a FAST-based
algorithm into their initial management of blunt trauma
victims.
Ballard
RB, Rozycki GS, Newman PG, Cubillos JE, et al. (1999). “An
algorithm to reduce the incidence of false-negative FAST
examinations in patients at high risk for occult injury.
Focused Assessment for the Sonographic Examination of the
Trauma patient.” J Am Coll Surg 189(2): 145-150; discussion
150-141.
BACKGROUND: The Focused Assessment for
the Sonographic Examination of the Trauma patient (FAST)
sequentially surveys for the presence or absence of blood
in dependent abdominal regions including the right upper
quadrant, left upper quadrant, and the pelvis. But it does
not readily identify intraparenchymal or retroperitoneal
injuries, and a CT scan of the abdomen may be needed to
reduce the incidence of missed injuries. We hypothesized
that select patients who are considered high risk for occult
injuries should undergo a CT scan of the abdomen when the
FAST is negative so that occult injuries can be detected.
STUDY DESIGN: An algorithm was prospectively tested for
the evaluation of select injured patients over a 3 1/2-year
period. Entrance criteria included adult patients with a
blunt mechanism of trauma, a negative FAST examination,
and a spine fracture (with or without cord injury), or a
pelvic fracture. Trauma team members performed the FAST
on patients during the Advanced Trauma Life Support secondary
survey. Data recorded included the patient's mechanism and
type of injury, the results of the FAST and CT scan examinations,
operative or postmortem findings or both, and patient outcomes.
Patients with spine injuries were grouped according to spine
level and the presence or absence of neurologic deficit.
The patients with pelvic fractures were grouped according
to the Young and Resnick classification. RESULTS: One hundred
two of 1,490 patients (6.8%) who had FAST examinations were
entered into this study. Thirty-two patients (30.5% ) had
spine injuries, with only one false-negative ultrasound
result. Seventy patients (68.6%) had pelvic fractures
with 13 false-negative ultrasound results: 11 ring (9 from
motor vehicle crashes, 2 from pedestrians struck), 1 acetabular,
and 1 isolated pelvic fracture. Nine patients underwent
nonoperative management for solid organ injuries, and 4
patients needed surgery. CONCLUSIONS: Based on these
preliminary data, we conclude that patients with pelvic
ring-type fractures should have CT scans of the abdomen
because of the higher yield for occult injuries.
Rozycki GS, Ochsner MG, Feliciano DV,
Thomas B, et al. (1998). “Early detection of hemoperitoneum
by ultrasound examination of the right upper quadrant: a
multicenter study.” J Trauma 45(5): 878-883.
BACKGROUND: The focused assessment for
the sonographic examination of the trauma patient (FAST)
is a rapid diagnostic test that sequentially surveys for
hemopericardium and then the right upper quadrant (RUQ),
left upper quadrant (LUQ), and pelvis for hemoperitoneum
in patients with potential truncal injuries. The sequence
of the abdominal part of the examination, however, has yet
to be validated. The objectives of this multicenter study
were as follows: ( 1) to determine where hemoperitoneum
is most frequently identified on positive FAST examinations;
and (2) to determine if a relationship exists between that
areas and the organs injured. METHODS: Ultrasound registries
from four Level I trauma centers identified patients who
had true-positive FAST examinations. Demographic data, areas
positive on the FAST, and organs injured were recorded;
injuries were classified as multiple, single solid organ
(liver or spleen) , isolated hollow viscus, or retroperitoneal.
Relationships between positive locations on the FAST examinations
and the associations of organs injured to areas positive
were assessed using McNamara's chi2 test; a p value < 0.05
was considered statistically significant. RESULTS: The RUQ
was the most common site where hemoperitoneum was detected,
and this was statistically significant compared with either
the LUQ or the pelvis. Also, statistically significant correlations
(p < 0.001) were observed between positive RUQ areas on
the FAST and multiple injuries, single solid organ (liver
or spleen) injury, and retroperitoneal injuries. CONCLUSION:
Blood is most often found on the FAST in the RUQ area in
patients with multiple intraperitoneal injuries or isolated
injury to the liver, spleen, or retroperitoneum, but not
when there is injury to a hollow viscus.
Paajanen H, Lahti P and Nordback I
(1999). “Sensitivity of transabdominal ultrasonography in
detection of intraperitoneal fluid in humans.” Eur Radiol
9(7): 1423-1425.
The sensitivity and specificity of ultrasonography
in detection of free intraperitoneal fluid is over 90 %.
The lowest detectable volume of free fluid in humans is
unknown. The distribution of intraperitoneal fluid was studied
in 86 patients by transabdominal US in group A (n = 21,
10 ml of fluid), in group B (n = 15, 50 ml of fluid) and
group C (n = 50, splenic trauma). Ultrasound detected fluid
in 15 of 21 patients in group A, and in all patients in
groups B and C. In group A 10 ml of fluid was found in 71
% of cases behind the bladder, and in only 5-14 % of cases
in the upper abdomen. In group B 50 ml of fluid was found
in all patients in the lower pelvis, but in only 20 % in
Morison's pouch and in 7 % around the spleen. In group C
200-4500 ml of fluid was detected by US in 72 % of patients
in the perisplenic space, in 60 % in Morison's pouch and
in 42 % in the retrovesical space. Small volumes of free
intraperitoneal fluid (10-50 ml) can be detected with current
US scanners, but only near the site of injury. These results
support the role of US as a primary imaging modality in
abdominal trauma.
Bain IM; Kirby RM; Tiwari P; McCaig
J; Cook AL; Oakley PA; Templeton J; Braithwaite M 'Survey
of abdominal ultrasound and diagnostic peritoneal lavage
for suspected intra-abdominal injury following blunt trauma.'
Injury, 1998 Jan, 29:1, 65-71
Over a 3 year period all severely injured
blunt trauma patients who were investigated with abdominal
ultrasound examinations (AUS) or diagnostic peritoneal lavage
(DPL) to exclude intra-abdominal injury were evaluated.
The ultrasound examinations were performed by radiologists
in 220 severely injured patients (20 of whom also had DPL).
The overall sensitivity and specificity of abdominal ultrasound
were 82.7% and 99.5%, respectively. The sensitivity increased
to 89.1% by repeat scanning. In comparison, 72 DPLs were
performed in severely injured patients; the overall sensitivity
and specificity of DPL were 82.8% and 97.2%, respectively.
DPL resulted in more non-therapeutic laparotomies, 9/25
(36%) compared with 3/23 (13%) with AUS. Abdominal ultrasound
is now the first line investigation at this centre for evaluation
of possible intra-abdominal injury in injured patients.
Guide to Evidence Appraisals
The definitions of the types of evidence
and the grading of recommendations used originate from the
US Agency for Health Care Policy and Research
| Evidence
obtained from meta-analysis of randomised controlled
trials |
| Evidence
obtained from at least one randomised controlled trial |
| Evidence
obtained from at least one well-designed controlled
study without randomisation |
| Evidence
obtained from at least one other type of well-designed
quasi-experimental study |
| Evidence
obtained from well-designed non-experimental descriptive
studies, such as comparative studies, correlation studies
and case control studies |
| Evidence
obtained from expert committee reports or opinions and/or
clinical experience of respected authorities |
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