Editorials Donald

R. Kirks,

MD

#{149} Kathleen

CT ofBlunt An Anatomic

H. Caron,

INCE the initial study by Berger and Kuhn in i98i (i), computed tomography (CT) has been increasingly used for evaluation of blunt abdominal trauma in infants and children. Prospective studies (2) and reviews (3) have documented the utility of CT in determining the presence and extent of injury in children with suspected abdominal injury after blunt trauma. The patterns of hepatic and splenic injury (4,5), bowel injury (6), and associated thoracic injuries (7) have been described in detail. Taylor et al (8) initially described the “hypoperfusion complex” secondary to hypovolemic shock in three patients less than 2 years of age. In this issue of Radiology, Sivit et al (9) further define the hypoperfusion cornin a total

of 27 children;

CT find-

ings were associated with both profound hernodynamic instability and poor prognosis. CT has become critical in the assessment and management of pediatric trauma; more than 2,000 patients at Children’s National Medical Center, Washington, DC, and Children’s Hospital Medical Center, Cincinnati (CHMC), have been evaluated with CT for blunt abdominal trauma. It should be stressed that not every child with blunt abdominal trauma should undergo imaging evaluation (iO). There are three general groups of pediatric trauma patients. Clinically stable patients with minor or trivial trauma require only careful clinical evaluation and observation. Clinically unstable children with severe head

Index

terms:

Abdomen,

men, injuries, 70.41 puted tomography children #{149}Editorials

Radiology

From

in infants #{149}Trauma

Corn-

#{149}

and

1992; 182:631-632

the

Department

Hospital

Medical

thesda

Ayes,

of Radiology, Center,

Cincinnati,

Departments

University Cincinnati.

Abdo-

#{149}

injuries

(CT),

dren’s

the

CT, 70.1211

Children,

#{149}

OH

of Radiology

of Cincinnati Received

cepted November to D.R.K. ( RSNA, 1992 See also the article in this issue.

College November

22. Address

by

Sivit

Chil-

Elland 45229-2899;

and

and and

Pediatrics,

Be-

S. Bisset

#{149} George

Abdominal “Snapshot

S

plex

MD

III, MD

Trauma in Children: in Time”

injury

and/or blunt abdominal trauma require immediate surgery. Finally, some pediatric patients have severe blunt abdominal trauma yet are cmically stable; CT has proved extremely valuable in this third group of patients (2,3,10). Because of recent advances in trauma support and improved patient survival, more seriously injured children are evaluated with CT (9). An increasing number of these patients with severe abdominal trauma have been resuscitated after hypovolemic shock and may demonstrate typical CT findings.

Pediatric

abdominal

CT in general

and CT of blunt abdominal trauma in particular require meticulous attention to technique (10,11). Our techniques at

CHMC

differ

slightly

from

those

scribed by Taylor and Federle (12);

et at (3,8) however,

mental

are similar.

principles

de-

and Jeffrey the funda-

Intrave-

graphy quent

require with

not only physielectrocardio-

and pulse oximetry clinical evaluation

but also frefor early signs

of shock. Unless the patient is comatose and at risk to aspirate, we give orally administered usual dose

contrast material for nonemergency

nal CT examination) tube

(half the abdomi-

via a nasogastric

approximately

10-15

fore the study. Although tion is rarely identified

minutes

be-

bowel perforaby means of

demonstration of extravasation of contrast material (3,6), we believe that orally administered contrast material provides optimal evaluation of the pancreas and bowel wall. A digital scout radiograph and three to four scout CT sections are obtained before intravenous administration of contrast material. This permits removal of tubes that might produce artifacts, assessment of adequacy of oral contrast material administration, verification of appropriate technique, accurate centering of the pa-

tient,

and

selection

of the appropriate

reprint

requests

field of view. Intravenously administered contrast material is given by means of rapid bolus hand injection; we routinely use nonionic contrast material

et al (pp

723-726)

in all patients.

of Medicine, 20, i99i; ac-

performed

Our with

examinations

a GE 9800

are

CT scanner

Systems,

table

with

Milwaukee), with sections obtained

through dynamic

incrementation

the lower scanning

is usually

performed. Contiguous scans of the lower abdomen and pelvis are obtained if pelvic injury is strongly suspected. Select, delayed images of the pelvis may be obtained to assess bladder integrity. A post-CT radiograph of the abdomen (“poor

man’s”

excretory

urogram)

is

frequently obtained to assess both upper and lower urinary tracts (10). CT shows the anatomy of the liver, spleen, kidneys, pancreas, peritoneal cavity, mesentery, and bowel. Despite the critical role of CT in evaluating blunt abdominal trauma in children, several potential pitfalls of the technique must be emphasized. Small traumatic

nous sedation is administered as necessary in consultation with pediatric trauma physicians. Patients who are comatose or who have been in shock

and resuscitated ologic monitoring

(GE Medical

contiguous i-cm-thick from the lung bases poles of the kidneys;

lesions

resolved.

of solid

creatic

injury,

bowel

perforation

difficult

may

diagnosis

intestinal

injury,

may

not

be

of panand

be extremely

(3,6,10).

In addition also

organs

Moreover,

allows

to depicting assessment

anatomy, of vascular

CT integ-

rity and inferring of the function of certam organs such as the liver, spleen, and kidneys. Described findings in the hypoperfusion complex (8,9) include small

size

cava,

presumably

of the

(12), and abnormal gans, presumably fusion.

aorta

and

due

inferior

vena

to hypovolemia

enhancement due to decreased

of orper-

It must be stressed that an abdominal CT study obtained after blunt abdominal trauma is an anatomic display at that point in time. Sivit et al (9) note that children may rapidly progress along

a continuum

from

compensated

to uncompensated to irreversible shock. Moreover, we have noted that there is also a spectrum traumatic shock

of CT findings and resuscitation

after in

children; not all of the defined findings are necessarily present at any given time. If hypovolemia is corrected during resuscitation, only abnormalities of endorgan perfusion are observed (Figure). We strongly agree with the previously published statement that “operafive or nonoperative approaches should

not be based on the extent of injury shown at CT, but on the physiologic condition

of the

child”

(5). This

is also 631

true of the hypoperfusion complex demonstrated at CT, which is merely a pictorial confirmation of what would be expected with a low Trauma Score and a low Glasgow Coma Score. These clinical tests allow accurate assessment of physiologic derangement and neurologic function on admission; they also provide prognostic information (9). In summary, Sivit et al should be congratulated on their ongoing clinical research that reconfirms the critical role of abdominal CT in children with suspected injury after blunt abdominal trauma. It is apparent that a number of

CT findings may be seen patient after resuscitation However,

tioned

radiologists

that

these

olemia and/or ing more than hemodynamic cance of these

in the pediatric for shock.

must

CT findings

also

References 1.

nal

of hypov-

PE, Kuhn

trauma

JP.

CT ofblunt

abdomi-

AJR

136:

in childhood.

1981;

105-110. 2.

3.

4.

Kaufman

RA,

7.

8.

role

of CT

et a!.

Potter BM, Eicheland splenic injury in the

decision

for

in lap-

arotomy. Radiology 1987; 165:643-646. Bulas DI, Taylor GA, Eichelberger MR. The value of CT in detecting bowel perforation in children after blunt abdominal trauma. AIR 1989; 153:561-564. Sivit CJ, Taylor GA, Eichelberger MR. Chest injury in children with blunt abdomma! trauma: evaluation with CT. Radiology 1989; 171:815-818. Taylor

GA,

Fallat

ME,

Eichelberger

shock

CT manifestations. 479-481. CJ,

Potter matic

BM, Eichelberger shock in children: with hernodynamic

ogy

1992;

Taylor

in children:

Radiology

Sivit

ated 10.

DS,

i986; 147:1199-1205.

Hypovolemic

9.

R, Babcock

Brick SH, Taylor GA, berger MR. Hepatic children:

6.

Towbin

Upper abdominal trauma in children: imaging evaluation. AJR 1984; 142:449-460. Taylor GA, Guion CJ, Potter BM, Eichelberger MR. CT of blunt abdominal trauma in children. AJR 1989; 153:555-559. Stalker HP, Kaufman RA, Towbin R. Patterns ofliver injury in childhood: CT analysis. AJR

5.

be cau-

hypoperfusion are nothan anatomic display of instability; the signififindings must be assessed in the context of the patient’s clinical status. It should not be assumed that significant visceral or bowel injuries are not also present. The decision for laparotomy is currently still based on the physiologic condition of the child rather than on the presence of any or all of the constellation of CT findings of the hypoperfusion complex. a

Berger

GA,

Bulas

MR.

after

DC,

MR. PosttrauCT findings associinstability. Radio!-

#{149} Radiology

posttraumatic

Blood pressure was normal at the time of the CT examination. There is marked stasis of contrast material in mesenteric vessels, indicating decreased bowel perfusion. Note normal

size

of the

aorta,

mesenteric

inferior

vein

due

tensive ischemic

central bowel

vena

and

artery,

nervous necrosis.

cava,

superior

to correction

volemia. The patient died CT examination. Autopsy

DR, Caron Ml. Gastrointestinal tract. In: Kirks DR. ed. Practical pediatric imaging: diagnostic radiology of infants and children. 2nd ed. Boston: Little, 1991;

823-828.

ii.

Kaufman dominal

of hypo-

18 hours after demonstrated

system

12.

RA.

Technical

CT in infants

injury

MP.

inferior

CT

vena

AJR

cava:

aspects and

1989; 153:549-554. Jeffrey RB, Federle volemia.

632

experiencing

CT scan and

the ex-

and

182:723-726.

Kirks

Brown,

resuscitated

complex; by automobile

shock

mesenteric

164:

DI, Kushner

of hypoperfusion of 9-year-old girl struck

superior

abdominal

1987;

Example

of ab-

children.

The evidence

AJR

collapsed of hypo-

1988; 150:431-432.

March

1992

CT of blunt abdominal trauma in children: an anatomic "snapshot in time".

Editorials Donald R. Kirks, MD #{149} Kathleen CT ofBlunt An Anatomic H. Caron, INCE the initial study by Berger and Kuhn in i98i (i), computed...
362KB Sizes 0 Downloads 0 Views