Blunt Abdominal Trauma: Injury to the Epigastrium

Blunt Abdominal Trauma: Injury to the Epigastrium

Mária

Némethy, Harvard Medical School, Year IIIGillian Lieberman, MD

Mária Némethy, HMS IIIGillian Lieberman, MDNovember 2004

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Blunt Abdominal Trauma (BAT)•

Trauma is the leading cause of death in the United States in persons under 45 years of age

•

Because it primarily affects the young, trauma causes more lost years of productive life than cancer and cardiovascular disease combined

•

Blunt trauma accounts for 2/3 of all injuries•

Majority of abdominal injuries are due to blunt trauma; 10% of trauma fatalities are due to abdominal injury

3


Mechanisms of injury•

Compression: direct blow or against a fixed object (seat belt, spinal column)–

Generally results in tears or subcapsular

hematomas in

solid organs–

Increased intraluminal

pressure can cause rupture of

hollow organs•

Deceleration: stretching and linear shearing between fixed and movable structures–

Rupture of supporting elements at junction between fixed and free segments of organs

–

Thrombosis of vessels contained within supporting elements

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Injuries resulting from blunt abdominal trauma

•

Common:–

Liver –

most commonly injured in all abdominal trauma

(blunt and penetrating)–

Spleen –

most commonly injured organ in blunt trauma

–

Kidney –

increasing frequency (increased detection)–

Bladder (extraperitoneal)

•

Rare:–

Pancreas

Adrenal

–

Bowel

Bladder (intraperitoneal)

5


First, a brief review of retroperitonal anatomy.

Note the crowding of the numerous soft organs in the epigastrium, with little bony protection. Unlike small bowel, these organs are fixed in place, and so cannot move out of the path of

blunt traumatic forces.

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Abdominal Retroperitoneum

Netter FH. Atlas of Human Anatomy, 2nd ed.

PancreasDuodenum(retroperitoneal)

Right kidneyLeft kidney

Inferior vena cava Abdominal aorta

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Epigastric

region

Netter FH. Atlas of Human Anatomy, 2nd ed.

IVC

Right adrenal

Right kidney

Duodenum

Transverse colon

Abdominalaorta

Left adrenal

Pancreas

Left kidney

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Options for evaluating BAT

•

Plain film–

Difficult to evaluate soft-tissue injury

–

May reveal free intraperitoneal

air or signs of bowel obstruction

•

Deep peritoneal lavage–

Rapid detection of hemoperitoneum

–

Invasive–

Risk of visceral and vascular injury

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Options for evaluating BAT•

CT – gold standard for BAT evaluation–

MDCT: high-resolution images and reconstructions allow improved detection and management of soft-

tissue injury, hemorrhage, etc•

Ultrasound –

increasing use

–

Safe for unstable patients; decreased costs–

Limitations: fluid-filled bowel versus hemoperitoneum; extraperitoneal

fluid versus intraperitoneal

fluid; cystic

masses can look like fluid collections; obesity•

MRI –

not used in initial evaluation of BAT

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Our Patient

JO, a 23-yr-old woman kicked in the stomach by a horse

●

Imaging at outside hospital suggested pancreatic injury; JO was

transferred to BIDMC for more complete evaluation

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Initial plain films were normal

Images from PACS, BIDMC

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CT: the diagnostic modality of choice in initial evaluation of

blunt abdominal trauma

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CT: pre-contrast


Mesenteric hematoma

Blood attenuation induodenal wall

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Post-contrast: Pancreatic injury


Fluid surrounding pancreas

Blood surrounding pancreatic head

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Pancreatic injury in BAT•

Epi: uncommon –

seen in 0.2-12% of blunt trauma

–

associated visceral injuries are very common (50-90% of patients)

•

Mechanism: –

compression against vertebral column

–

shear across pancreatic neck•

Sequelae:

Ductal

leakage pancreatitis, which can

lead to pseudocysts, fistulas and abscesses (20% mortality)

•

Grading: based on injury to main pancreatic duct:–

minor injuries usually heal spontaneously and are treated conservatively

–

injuries involving main pancreatic duct require surgical intervention

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CT findings in pancreatic injury•

CT sens/spec for pancreatic injury over 80%; dependence on interpreter experience and timing of evaluation

•

Contusion: areas of low attenuation with heterogeneous foci and diffuse enlargement of pancreas

•

Laceration: areas of linear, irregular low attenuation within normal parenchyma

•

Nonspecific: thickening of anterior pararenal

fascia; blood/fluid tracking along mesenteric vessels; fluid in lesser sac; fluid between pancreas and splenic

vein

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Image from PACS, BIDMCImage from PACS, BIDMC

Ischemic kidney

Extravasation

of IV contrast

Renal injury

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Renal injuryRight kidney Left kidney


Ischemic kidney

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Renal injury in BAT•

Epi:

Seen in 10% of trauma patients; blunt trauma

accounts for 80% of renal injuries–

Left-sided predominance (1.3:1) –

thought to be due to

anatomic protection of right renal artery beneath inferior vena cava and duodenum

•

Mechanism: –

sudden deceleration/direct blow can cause renal dislocation

–

stretching of renal arteries can cause immediate avulsion or delayed thrombosis

•

Sequelae: 80% are contusions/minor lacerations that heal spontaneously; persistent bleeding or complete infarction require surgical intervention

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CT findings in renal injury•

CT important in both diagnosis and patient management: provides both functional and morphologic information

•

Absence of contrast nephrogram

reveals devascularized

areas

•

Helical CT can image specific renal artery injury•

Contusion: delayed and non-homogenous excretion of contrast material

•

Laceration: linear or wedge-shaped hypodensity•

Fracture: involvement of full depth of renal parenchyma + disruption of collecting system

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Duodenal hematoma

Image from PACS, BIDMC

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Duodenal injury in BAT•

Epi: Bowel injury seen in 4-5% of major BAT; associated non-bowel injuries in 50%–

Retroperitoneal duodenum most common site of injury

–

Duodenal hematomas are very uncommon!•

Mechanism:–

Compression between spine and impacting body;

–

Shearing at fixed points (e.g. ligament of Treitz)•

Sequelae:–

Duodenal hematoma: resolves in 1-3 weeks

–

Duodenal perforation: surgical intervention required

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CT findings in duodenal injury

•

Nonspecific (perforation vs. hematoma): –

Thickening of duodenal wall

–

Presence of fluid in right anterior pararenal

space•

Specific to perforation: Extraluminal

gas and/or

oral contrast in right anterior pararenal

space•

Duodenal hematoma: –

Initial heterogeneous, high attenuation region in duodenal wall due to blood accumulation

–

Isodensity, then hypodensity

as clot resolves

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Intraperitoneal

bleedingUterus

Air in rectum

Intraperitoneal

bloodin Douglas’

pouch(HU = 50)


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Intraperitoneal

fluid in BAT

•

Is often sole finding on CT in blunt abdominal trauma

•

Tracks down right and left paracolic gutters into pelvic reflection of peritoneum

•

Large amounts of blood can accumulate in pelvis without significant hemoperitoneum

apparent in upper abdomen

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CT: detection of intraperitoneal

fluid•

CT very sensitive for detecting even small amounts of intraperitoneal

fluid or hemorrhage

•

“Sentinel clot”

sign: with multiple sites of hemoperitoneum, blood with highest CT attenuation is in proximity of site of hemorrhage

•

Blood attenuation on CT:–

Free blood: 20-45 HU

–

Clotted blood: 40-100 HU–

Active bleeding: within 10 HU of contrast density inside adjacent major vessel

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How extensive was the pancreatic injury?

…The role of MRI…

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MRI: characterization of soft tissue injury

•

MRI is more sensitive for soft tissue anatomy and pathology

•

No advantage over CT in initial evaluation, but can be invaluable in characterization of subtle soft tissue injury, as in the pancreas

•

Role of MRCP: evaluate damage to pancreatic duct –

key factor in surgical

versus conservative treatment

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Pancreatic injury: characterization with MRI


Lacerations in head of pancreas

Pancreatic headcontusion

Laceration in bodyof pancreas

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Duodenal hematoma on MRI


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Sequelae•

JO was admitted to BIDMC one day after the injury

•

Her intra-abdominal injuries were managed conservatively (MRCP did not show laceration of pancreatic duct)

•

PICC line was placed on day two post-injury; initial inappropriate placement corrected on day three

•

Follow-up CT imaging was performed 10 days after initial CT–

the findings…?

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10-day follow-up: Pancreatic pseudocyst


Pseudocyst

Pancreatic tissue

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Pancreatic pseudocyst


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Why did the kidney not infarct completely??

•

Initial work-up demonstrated ischemic lower pole in left kidney

•

Extravasation

of IV contrast into peritoneal cavity would suggest transection

of renal

artery•

Follow-up CT indicated improved perfusion of lower renal pole

•

Interesting anatomy…

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Bilateral accessory renal arteries


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Accessory renal arteries

•

Transection

of inferior accessory renal artery originating from common iliac artery, leading to contrast extravasation

and

infarct of inferior renal pole•

Development of collateral perfusion from main renal artery and remaining accessory renal artery

37


Our patient’s course

•

JO had a stable hospital course, and was discharged home 13 days after admission

•

Incidental note: JO received a PICC line for parenteral

nutrition. Initial follow-up

CXR revealed inappropriate positioning of the line….

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PICC line terminating in L jugular vein


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The PICC line was repositioned, and subsequently revealed some more

interesting anatomy….

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A Left-sided SVC!


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Acknowledgements

•

Michael Goldfinger, MD•

Gillian Lieberman, MD

•

Pamela Lepkowski•

Larry Barbaras, Webmaster

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References•

Becker CD, et al. Blunt abdominal trauma in adults: role of CT in the diagnosis and management of visceral injuries. Eur

Radiol

1998;8:772-80.•

Bradley EL III, et al. Diagnosis and initial management of blunt pancreatic trauma. Ann Surg

1998;227(6):861-9.•

Bruce LM, et al. Blunt renal artery injury: incidence, diagnosis, and management. Am Surg

2001;67(6):550-5.•

Dodds

WJ, et al. Traumatic fracture of the pancreas: CT characteristics. J Comp

Assist Tomography 1990;14(3):375-8.

•

Fischer JH, Carpenter KD, O’Keefe GE. CT diagnosis of an isolated blunt pancreatic injury. AJR 1996;167:1152.

•

Fuchs WA and Robotti

G. The diagnostic impact of computed tomography in blunt abdominal trauma. Clin

Radiol

1983;34:261-5.•

Klausner

JM, et al. Intramural haematoma

of the duodenum following blunt abdominal injury –

the place for conservative treatment. Injury 1986;17:131-2.•

Kunin

JR, et al. Duodenal injuries caused by blunt abdominal trauma: Value of CT in differentiating perforation from hematoma. AJR 1993;160:1221-3.

•

Lupetin

AR, Mainwaring BL, Daffner

RH. CT diagnosis of renal artery injury caused by blunt abdominal trauma. AJR 1989;153:1065-8.

•

McGehee

M, et al. Comparison of MRI with postcontrast

CT for the evaluation of acute abdominal trauma. J Comp Assist Tomography 1993;17(3):410-3.

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References•

McKenney

KL. Ultrasound of blunt abdominal trauma. Radiol

Clin

N Am 1999;37(5):879-93.

•

Mirvis

SE and Shanmuganathan

K. Abdominal computed tomography in blunt abdominal trauma. Sem

Roentgen 1992;27(3):150-83.•

Netter FH. Atlas of Human Anatomy, 2nd ed. East Hanover, NJ: Novartis, 1999.•

Parker GD and Williams JAR. Massive intramural duodenal haematoma

following blunt abdominal trauma: case report. Australas

Radiol

1989;33:19204.•

Porter JM and Singh Y. Value of computed tomography in the evaluation of retroperitoneal organ injury in blunt abdominal trauma. Am J Emerg

Med 1998;16(3):225-7.

•

Sidhu

MK, Weinberger E, Healey P. Intramural duodenal hematoma after blunt abdominal injury. AJR 1998;170:38.

•

Shanmuganathan

K. Multi-detector row CT imaging of blunt abdominal trauma. Sem

Ultrasound CT MRI 2004;25(2):180-204.•

Shuman WP. CT of blunt abdominal trauma in adults. Radiology 1997;205:297-

306.

•

Thomsen TW, Brown DFM, Nadel

ES. Blunt renal trauma. J Emerg

Med 2004;26(3):331-7.

•

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Blunt Abdominal Trauma: Injury to the Epigastrium