Page 1642 - Hall et al (2015) Principles of Critical Care-McGraw-Hill

CHAPTER 120: Torso Trauma 1161

antibiotics that will cover aerobic gram-negative and anaerobic organ- Its main use, therefore, is in relatively stable patients, particularly those
isms. It is crucial that the antibiotics be administered before the incision who are already having CT for another indication, such as possible
is made in order to minimize septic complications. If there is no fecal head injury. The main advantages of ultrasound are its rapidity, sensi-
contamination in the peritoneal cavity, the antibiotics may be stopped tivity, noninvasiveness, and portability. Where emergency ultrasound
within 24 hours. However, in the presence of contamination, antibiotic assessment is available (focused assessment for the sonographic exami-
administration should be continued until the temperature is normal and nation of the trauma patient [FAST]), this is preferred and superior
there is no leukocytosis. An increase in the temperature and white blood to DPL but, like all imaging techniques, is not sufficiently sensitive to
cell (WBC) count after antibiotics are stopped suggests residual sepsis, be used in isolation to make judgments regarding the need for sur-
which often is in the form of an undrained intra-abdominal abscess. gery. With proper training of personnel, FAST can be very accurate in
A generous upper midline incision extending from the xiphoid process detecting hemoperitoneum, even when conducted and interpreted by
to just below the umbilicus is the exposure of choice because most of the nonradiologists. With the almost universal availability of FAST in most
https://kat.cr/user/tahir99/
lesions producing instability arise from injuries to the upper abdominal emergency rooms, DPL is very seldom used in assessing the injured
contents. This incision can be extended easily up into the chest through abdomen.
lateral thoracotomy or a median sternotomy or extended into the lower Like other investigative tools, peritoneal lavage, ultrasound, and CT
abdomen for lower abdominal injuries. Occasionally, the history suggests should be used only if the results will affect the decision on whether to
an isolated lower abdominal injury, and in this circumstance, a lower perform a laparotomy. If there is an obvious need for laparotomy, then
midline incision beginning at the umbilicus may be undertaken. these modalities are not indicated.
Prior to laparotomy, the surgeon only needs to decide whether sur-
gical intervention is required; a specific diagnosis is not necessary. In Indications for These Investigations
deciding on laparotomy, one looks for the signs of penetration, perfora- 1. When there are equivocal abdominal findings in torso trauma.
tion, or hemorrhage. Penetration of the peritoneum in stab wounds is Certain conditions, such as fractures of the lower ribs, pelvis, or
diagnosed by exploration of the abdominal wound under local anesthe- lumbar spine, may produce abdominal signs that are difficult to
sia with good lighting; if it is determined that the peritoneum has been differentiate from those due to intra-abdominal injury.
violated, in most instances laparotomy is performed. This approach has 2. When abdominal findings are impossible to elicit (eg, when pain
been questioned, and peritoneal lavage or laparoscopy has been con- perception is abnormal, such as with severe head injury, drug intoxi-
ducted in conjunction with exploration of the wound to determine the cation, or spinal cord injuries).
need for laparotomy on a more selective basis. In these circumstances,
demonstration of violation of the peritoneum and positive peritoneal 3. When there may be long periods during which the patient is
lavage are used as indications for laparotomy. All bullet wounds to unavailable for repeated physical examination and observation,
the abdomen are generally treated by laparotomy, although a selective such as during lengthy surgical procedures, eg, orthopedic or intra-
approach based on careful scanning of the abdomen to identify tangen- abdominal procedures.
tial nonpenetrating wounds has been reported. The signs of perforation 4. When there is an obvious source of hemorrhage, such as a pelvic or
are abdominal pain, tenderness, guarding, and rigidity. Signs of hemor- extremity fracture, which could account for hypotension, but when
rhage also may present with signs of peritoneal irritation, shoulder tip simultaneous intra-abdominal bleeding needs to be excluded.
pain, or variable degrees of hemodynamic instability.
On entry into the peritoneal cavity, the presence of dark blood usu- Contraindications: An absolute contraindication to DPL is an already
ally suggests a liver injury, whereas bright red blood suggests an arterial identified indication for laparotomy. Relative contraindications to
source of bleeding. Rapid evisceration of the small intestine and liberal DPL include previous abdominal operations with scars in the abdo-
use of packs wherever blood is accumulating allow identification of the men, morbid obesity, a preexisting coagulopathy, and advanced preg-
source of blood loss. Otherwise, orderly packing starting with the lateral nancy. An incision may be made above the umbilicus in advanced
gutters, the pelvis, and then solid organs is conducted. Concentration pregnancy or distant from prior surgical wounds, and the open
on the first site of bleeding should be avoided. The lesions should be technique is preferable. There are virtually no contraindications to
approached in order of severity; that is, the areas that are bleeding most ultrasound assessment of the traumatized abdomen except an obvious
briskly should be treated first. need for laparotomy on the basis of clinical examination alone. The
In general, findings on physical examination determine the need for relative contraindication to CT is instability of the patient that makes
surgical intervention. There are situations, however, in which the signs transfer to the CT suite unsafe.
may be equivocal or impossible to elicit in the unstable patient. In these Selecting the Diagnostic Modality in Blunt Abdominal Trauma:
circumstances, ultrasound, peritoneal lavage, and CT are all very helpful Hemoperitoneum is the major indication for laparotomy in blunt
in determining the need for laparotomy. abdominal trauma. Therefore, a diagnostic technique other than physical
Massive intra-abdominal hemorrhage may require thoracotomy to examination that detects hemoperitoneum accurately, quickly, noninva-
allow clamping of the supradiaphragmatic aorta for temporary control sively, and with minimal cost, such as ultrasound, appears most attrac-
of intra-abdominal hemorrhage and the maintenance of perfusion to the tive. However, there is still a role for other modalities, such as DPL and
brain and myocardium. Prompt laparotomy after aortic clamping would CT, in the assessment of the patient sustaining blunt abdominal trauma.
allow identification and control of intra-abdominal hemorrhage before If the ultrasound examination is negative, the patient may be followed
release of the aortic clamp. In many instances, aortic clamping also may clinically without the need for CT or DPL. Change in the patient’s status
be achieved through a laparotomy with compression and/or clamping of warrants consideration for repeat ultrasound or CT evaluation. With an
the infradiaphragmatic abdominal aorta. equivocal ultrasound examination in a stable patient suspected of having
■ ROLE OF PERITONEAL LAVAGE, CT, AND ULTRASOUND IN ASSESSING intra-abdominal injury, CT should be done. An unstable patient with an

ABDOMINAL TRAUMA equivocal ultrasound examination should either have a DPL or be taken
directly to the OR. When the ultrasound examination in a stable patient
Diagnostic peritoneal lavage (DPL), ultrasound, and CT are all useful is positive for hemoperitoneum and a more specific diagnosis is desired,
diagnostic tools in assessing the traumatized abdomen. These modalities CT should be conducted. CT is particularly useful in patients who have
are all very sensitive for the detection of hemoperitoneum. Of the three hemoperitoneum with solid-organ injury that may be treated nonopera-
modalities, CT is the most specific. However, it requires transporting tively. The unstable patient in whom ultrasound examination is positive for
the patient to the CT suite and is relatively costly and time-consuming. hemoperitoneum requires laparotomy.

section10.indd 1161 1/20/2015 9:21:10 AM