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Blunt Abdominal Trauma
Roger Sa adia
Definition of a heavy trauma: somebody who arrives at the hospital in more than
one ambulance. (John Edwards)
He should have a special love for the wounded persons as for his own
body. (Hans von Gersdorff, 1480–1540)
Differences Between Blunt and Penetrating Trauma
There are several differences between blunt and penetrating trauma injuries:
Penetrating abdominal trauma is made obvious by the presence of a wound.
Blunt abdominal trauma is sometimes unequivocally identifiable by the presence of a visible contusion of the abdominal wall (e.g., seat belt sign), but more
frequently, it is only suspected from the mechanism of injury.
Penetrating abdominal trauma is usually confined to the abdomen. Common
mechanisms of blunt trauma (vehicle accidents, falls, beatings, etc.) often result
in polytrauma, the abdominal component being associated with other cavity or
system injuries (head, chest, pelvis, vertebral column, long bones).
The patterns of intra-abdominal visceral injuries are different. Hollow viscera
injuries are common in penetrating trauma. They are very rare in blunt trauma,
where solid organ injuries (to liver, spleen, pancreas) predominate.
39.1
Clinical Evaluation Is Unreliable
Clinical evaluation is unreliable due to several factors:
There is frequent presence of a head injury with decreased level of con-
sciousness.
The nature of multisystem trauma results in “distracting” injuries by which
the pain experienced at other sites (chest, long bones, etc.) masks or distorts the
patient’s perception of abdominal pain and tenderness.
While hypotension is frequently caused by an injured intra-abdominal
solid organ, it is as frequently due to an associated long-bone fracture or a hemothorax. It may even not be the result of hypovolemic shock but represent a
sign of cardiogenic (due to cardiac contusion, pericardial tamponade, tension
pneumothorax) or spinal shock.
Roger Saadia
University of Manitoba and Health Sciences Centre, Winnipeg, MB, Canada R 3M 3G5
M. Schein et al. (eds.), Schein’s Common Sense Emergency Abdominal Surger y,
DOI: 10.1007/978-3-540-74821-2_39.1, © Springer-Verlag Berlin Heidelberg 2010
417
418 Roger Saadia
Fig. 39.1.1. “So what’s wrong inside your black box”?
Tenderness on palpation may be the result of bruising of the abdominal wall
rather than reflect a more severe intra-abdominal injury.
In blunt abdominal trauma, unlike in penetrating injuries, the reliance on
clinical pictures of shock or peritonitis cannot constitute the sole justification for
a laparotomy. The abdomen in blunt trauma has come to be seen as a “black box”
>
(
Fig. 39.1.1), in other words, an uncertain source for the patient’s current instability
or subsequent deterioration. It is therefore imperative to resort to additional diagnostic tests. The aims of these investigations are not only to confirm the presence of
abdominal trauma, but also, whenever possible, to document as precisely as possible
the nature of the visceral injuries since their treatment is not invariably surgical.
Adjunctive Diagnostic Tests
There are three main diagnostic tests used in blunt trauma: diagnostic peritoneal lavage (DPL), ultrasound scan (referred to as FAST, focused abdominal
sonography for trauma), and helical computed tomography (CT) scan. In modern,
well-equipped centers, abdominal CT scan is the investigation of choice in the
stable patient, while DPL and more frequently FAST are employed when the patient is hemodynamically unstable. The last two tests could also be used more
liberally in facilities that cannot offer unrestricted access to CT scanning.
Diagnostic Peritoneal Lavage
Both a nasogastric tube and a Foley catheter are first inserted in preparation
for the DPL (it would be a pity to puncture the stomach or the bladder!). The technique entails the placement, under local anesthesia, of a catheter into the peritoneal
39.1 Blunt Abdominal Trauma 419
cavity. One liter of warmed saline is thereby infused, given a moment to mix with
the intraperitoneal contents, and recovered by laying the bag on the floor.
The DPL is deemed positive in cases of:
Aspiration of blood from the catheter on insertion (“grossly positive DPL”).
Presence of more than 100,000 red blood cells per cubic millimeter in the
effluent (“microscopically positive DPL”).
Presence of bile, intestinal contents, or urine in the effluent.
Presence of more than 10,000 white blood cells per cubic millimeter in the
effluent (this is controversial).
Flowing of the DPL fluid through the urinary catheter or the chest tube, indi-
cating a bladder or diaphragmatic injury, respectively (these scenarios are rare).
Historically, DPL was the diagnostic gold standard for blunt abdominal
trauma, but in recent times it has lost its shine for the following reasons:
It is cumbersome and difficult to perform in a combative or obese patient.
It has absolute or relative contraindications: previous surgery, pregnancy.
It is invasive and attended by a small complication rate (bowel perforation).
Most important, if laparotomies were to be performed for all instances of mi-
croscopically or even grossly positive DPL, the rate of non-therapeutic laparotomies
would be unacceptably high because, in most cases, the source of bleeding could
have been treated nonoperatively. Of course, an unnecessary laparotomy carries
a significant morbidity in the context of multisystem trauma.
In modern centers, DPL is used only in the very unstable patient to confirm,
preoperatively, the presence of a large hemoperitoneum. If your hospital lacks
access to the more sophisticated investigations, do remember that a negative DPL
is a crucial piece of information in ruling out the “black abdominal box” as a
source for concern in a severe, multisystem trauma patient.
Focused Abdominal Sonography for Trauma
The aim of FAST is to detect the presence of free fluid in the following areas:
The pericardial sac
Morrison’s (hepatorenal) pouch in the right upper abdominal quadrant
The splenorenal recess in the left upper abdominal quadrant
The pelvis
FAST can assist in the diagnosis of pericardial tamponade (a rather rare finding in blunt trauma). In the evaluation of the abdomen, it duplicates somewhat the
role of DPL with the advantages of being relatively cheap, totally noninvasive, and
applicable at the patient’s bedside. FAST is reliable only in the hands of personnel
specially trained in the technique (surgeons, emergency room physicians, radiologists) and in centers with a high case volume. In modern centers, FAST plays an
420 Roger Saadia
important role in the assessment of the unstable trauma patient; a laparotomy is
usually indicated in a hypotensive patient found to have a large amount of free
intraperitoneal fluid. It is also commonly used in stable patients, but more as a
practice exercise rather than a test allowing for definitive decision making. The
use of FAST as a screening tool for abdominal CT scanning is more controversial.
Computed Tomography
Computed tomographic scanning has become an essential part of the modern management of the stable blunt multitrauma patient. It is very common now
to dispense with the cervical spine X-rays, the thoracolumbar spine X-rays, the
pelvic X-ray, and even sometimes the chest X-ray; the patient is taken instead to a
radiology suite adjacent to the resuscitation room, and a quadruple scan of the
head, neck, chest, and abdomen (including the vertebral column and the pelvis) is
obtained in a few minutes.
The abdominal component of this diagnostic workup is extremely valuable
because:
Both the peritoneal cavity and the retroperitoneum can be assessed.
The integrity of bony structures (lumbar spine, pelvis) can be ascertained.
A precise inventory of injuries to solid intraperitoneal (liver, spleen) and
retroperitoneal (pancreas, kidneys) organs can be made; these injuries can be accurately graded.
The new-generation scanners are able to detect intestinal injuries (sug-
gested by mesenteric stranding, bowel thickening, or extraluminal air).
Free fluid (with radiological blood density) in the absence of solid organ
injury can be detected, suggesting the presence of a significant mesenteric injury.
In equivocal CT scan findings, clinical judgment is essential; a repeat CT
scan 24 hrs later, clinical observation, or immediate laparotomy are the main
options to be weighed.
The recourse to “total body scanning” has become so unregulated in some
“high-tech” centers that a note of caution needs to be sounded:
Cost aside, liberal “trauma scannograms” deliver a very high dose of
radiation; this, combined with the recurrent need for CT scanning through an entire lifetime, carries a significant long-term cancer risk. Always ask yourself when
sending a trauma patient to the scanner whether a quadruple test is essential in
this particular patient. Could not, for example, the chest CT be replaced by a simple
chest X-ray? An easy way to keep in mind this danger is to remember the acronym
VOMIT (victims of modern imaging technology) coined by Hayward (BMJ, 2003).
Only stable or well-resuscitated patients can be put through the scanner.
Borderline patients can decompensate catastrophically in the radiology suite.
39.1 Blunt Abdominal Trauma 421
CT images are as good as their interpreter. In the middle of the night, expert
radiologists are rarely available. Always keep your clinical judgment on high alert,
especially when there is discordance between clinical picture and CT images. Remember BARF (brainless application of radiological findings) and reach for an
antiemetic.
Nonoperative Management of Solid Organ Injuries
in Blunt Trauma
The majority of patients with blunt splenic or hepatic injury (and almost all the
patients with an isolated blunt renal injury) can be treated conservatively. Once such
an injury has been identified on CT scan and provided there is no clinical or radiological evidence of an associated hollow viscus injury, nonoperative management
can be attempted. The hemodynamic status rather than the radiological grade of the
injury constitutes the basis for therapeutic decision making; the grade of injury has
merely predictive value in the success of conservative management. The patient is
admitted for the first 24 hrs to a high-care unit for close observation. Continuous
vital signs and urine output monitoring, serial abdominal examinations, and repeated hemoglobin evaluation are conducted. Then, with every passing day on the
ward with no sign of ongoing bleeding, the success of the conservative approach
becomes more likely. Repeat CT scans are not required routinely on this admission
but only if complications occur. On discharge, the patient is cautioned to avoid putting the injured organ at risk of a secondary rupture (e.g., contact sports, bar-room
brawls) until a CT scan 8–12 weeks later documents complete healing. More subtle
differences between splenic or hepatic injuries should now be pointed out.
Spleen
Nonoperative management of a splenic injury should not be stubbornly continued in the face of an increased requirement for blood transfusion. When there
are episodes of hypotension (unexplained by extra-abdominal injuries) or a sustained drop in hemoglobin (not accounted for by hemodilution), there should be a
low threshold for splenectomy, especially in the adult. It is a real tragedy to lose a
patient from splenic hemorrhage when definitive control of the bleeding can be
achieved by a simple surgical procedure, namely, a splenectomy (acrobatic splenic
salvage procedures belong to the past). The very small risk of postsplenectomy sep-
sis in the adult can be further minimized by patient education and vaccination
(anti-Pneumococcus, anti-Meningococcus, and anti-Hemophilus influenzae). There
is a range of opinions about the trigger for abandoning conservative management.
Some believe that untreated hypotension alone (from a presumed splenic source)
justifies intervention; others are prepared to transfuse up to a maximum of two
units of blood before changing course. The message is clear: do not persevere with
422 Roger Saadia
multiple blood transfusions to treat ongoing splenic bleeding. The initial CT scan
may reveal a contrast “blush” in the splenic parenchyma pointing to active bleeding;
there is evidence to suggest that routine angioembolization of these bleeding vessels, in the stable patient, increases the success rate of nonoperative management.
Liver
The intraoperative control of hepatic bleeding is difficult. The loss of the
tamponade effect at laparotomy followed by mobilization of the liver can result in
renewed hemorrhage, sometimes torrential. In tackling a bleeding liver, there is no
equivalent to a simple procedure like a splenectomy. Therefore, more diligence is
called for in the pursuit of conservative management, as well as a greater reliance
on aggressive transfusions of blood products and factors. There has been increasing recourse to angioembolization in attempts (often successful) to avoid surgery.
With hepatic injuries treated nonoperatively, there is a higher complication rate
than with splenic injuries. Increasing right upper quadrant pain, jaundice, melena,
or sepsis should prompt specialized investigations (repeat CT scan, ERCP, angiography). Most of these complications can be treated by interventional radiology.
When to Operate in Blunt Trauma?
The most common indications for surgery in blunt trauma are:
The hemodynamically unstable patient with a significant hemoperitoneum
preferably demonstrated by DPL or FAST. These investigations may be omitted
when other extra-abdominal injuries are confidently ruled out in a hypotensive
patient with a tense, distended abdomen.
The patient with an acute posttraumatic diaphragmatic hernia demon-
strated on chest X-ray or CT scan.
The patient with or without peritoneal signs but with free intraperitoneal
air demonstrated on an upright chest X-ray or abdominal CT scan.
The patient with a hollow viscus injury (bowel, gallbladder, intraperitoneal
urinary bladder) demonstrated clinically or on CT scan.
The patient with CT evidence of a significant pancreatic injury.
The patient with a significant hemoperitoneum in the absence, on CT scan,
of solid organ injury; think of a severe mesenteric injury with a potential for
bowel ischemia.
The patient with signs of sepsis or a persistently tender abdomen in the
presence of equivocal CT images.
The patient in whom conservative management of a hepatic or splenic
injury (identified initially by CT scan) has failed.
(For the operative management of these specific injuries, see > Chap. 39.2.)
39.1 Blunt Abdominal Trauma 423
Conclusion
Clinical evaluation is often unreliable in the management of blunt abdominal trauma. Great reliance is placed on the abdominal CT scan in stable patients
and on DPL or FAST in hypotensive patients. The results of these investigations
always need interpretation in the overall clinical context.
Things have changed since a century ago when it was stated:
“Exploratory laparotomy offers, in our judgment, the quickest and the safest method
of positive diagnosis. The emergency warrants a decisive step.” (Albert Miles, 1893)
Operative Management
of Individual Organ Injuries
Roger Sa adia
We will always start with the most dangerously injured without regard
to rank and distinction. (Jean Larrey —Napoleon’s surgeon; 1766–1842)
You have decided to perform a laparotomy. Currently, this is more likely for
penetrating than for blunt trauma. Most solid visceral injuries in blunt trauma
can be managed conservatively: often doing “less” is “better,” with limited blood
loss and avoidance of unnecessary tissue injury fueling the inflammatory response
in a patient with frequently associated extra-abdominal injuries (> Chap. 54). The
incision and the assessment of the damage are described elsewhere (> Chaps. 10
and 11, respectively).
Diaphragm
A through-and-through diaphragmatic laceration requires suture repair
with heavy, interrupted suture material. Lacerations with substantial tissue loss
are rare and need repair with a synthetic mesh patch. A prosthesis may not be necessary when the tissue loss is at the periphery; instead, the diaphragm can be reimplanted to the ribs more cephalad. This is of particular benefit in the presence of
extensive contamination. Remember that even in the absence of a preoperative
pneumothorax, an ipsilateral chest tube must be inserted at some stage of the procedure. It is often said that minor diaphragmatic tears can be ignored on the right
side because the bulk of the liver prevents future bowel herniation. However, large
right-sided lacerations (seen usually in blunt trauma) must be repaired because
the liver itself can, in time, be “sucked up” into the chest.
39.2
Roger Saadia
University of Manitoba and Health Sciences Centre, Winnipeg, MB, Canada R 3M 3G5
M. Schein et al. (eds.), Schein’s Common Sense Emergency Abdominal Surger y,
DOI: 10.1007/978-3-540-74821-2_39.2 , © Springer-Verlag Berlin Heidelberg 2010
425
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