abdominal emergency cases

Abdominal Emergency Cases

Jeff Dunkle, MD

February 2011

Case: Trauma

Dx: “Shock Bowel”

Hypoperfusion complex

Seen in patients with hypovolemic shock.

Poor prognostic indicator.

CT findings are generally reversible.

Increased permeability.

Edema

Enhancement

Dx: Hypoperfusion complex

Small bowel mucosal

enhancement

Adrenal hyperenhancement

Abnormal parenchymal

organ enhancement

Small IVC, Aorta

Blunt Abdominal Trauma

A few stats:

Trauma is the leading cause of death in US for those < 44 y.o.

For those age 15-34, MVA is single leading cause of death.

Blunt Abdominal Trauma

Prevailing trends:

MDCT is test of choice

Non-operative management is favored whenever feasible.

Case: Pain.

Dx: Pneumoperitoneum.

Case: Pregnant, pain.

Dx: Ectopic Pregnancy

Case: Pregnant. Pain.

Case: cont’d

Case: Trauma.

Dx: Grade II hepatic injury

Grade II injury

Laceration 1-3cm depth

Subcapsular hematoma 10-

50% surface area of liver

Intraparenchymal

hematoma < 10 cm.

AAST Liver Injury Grading

I Hematoma: subcapsular, <10% surface area

Laceration: capsular tear, <1 cm in parenchymal depth

II Hematoma: subcapsular, 10%–50% surface area; intraparenchymal, <10 cm in diameter

Laceration: 1–3 cm in parenchymal depth

III Hematoma: subcapsular, >50% surface area or expanding or ruptured subcapsular hematoma with active bleeding; intraparenchymal, >10 cm or expanding or ruptured

Laceration: >3 cm in parenchymal depth

IV Hematoma: ruptured intraparenchymal hematoma with active bleeding

Laceration: parenchymal disruption involving 25%–75% of a hepatic lobe or 1- 3 Couinaud segments within a single lobe

V Laceration: parenchymal disruption involving >75% of a hepatic lobe or >3 Couinaud segments within a single lobe

Vascular: juxtahepatic venous injuries (i.e.: retrohepatic vena cava or central major hepatic veins)

Advance 1 grade for multiple injuries up to Grade III

Injury grading

AAST injury grading. Why?

Why not?

AAST grade of injury is an independent predictor of failure of non-operative management

Other predictors of NOM failure: Need for multiple blood transfusions

Hypotension

Age

AAST injury grading

Higher grade increases probability of delayed complications

Delayed complications: delayed hemorrhage, pseudoaneurysm formation, AV fistula, biloma, infected hematoma, pseudocyst, urinoma

Surgeons use grading system to triage management

Pitfalls of CT Grading

Congenital clefts; most commonly in spleen

Streak artifact simulating linear laceration

Patient’s arms

Ribs

Cardiac leads

Other: focal fatty infiltration (liver) or other hypoattenuating

lesions

Case: Trauma.

Dx: Grade IV liver injury

Grade III Laceration >3cm in depth

Large subcapsular or intraparenchymal hematoma

Grade IV Laceration involving 25-75% of a

lobe

Ruptured intraparenchymal hematoma with active bleeding

Grade V Laceration involving > 75% of a

lobe

Major juxta-hepatic venous injury

Case: Trauma.

Dx: Grade II splenic injury

Grade II injury:

Laceration 1-3cm in depth

Parenchymal hematoma

<5cm

Subcapsular hematoma 10-

50% surface area of spleen

AAST Splenic Injury Grading

I Subcapsular hematoma < 10% surface area

Capsular laceration < 1 cm parenchymal depth

II Subcapsular hematoma, 10%–50% surface area

Intraparenchymal hematoma <5 cm diameter

Laceration with 1–3 cm parenchymal depth, not involving a trabecular vessel

III Subcapsular hematoma >50% surface area or expanding

Ruptured subcapsular or parenchymal hematoma; intraparenchymal hematoma

>5 cm

Laceration >3 cm parenchymal depth or involving trabecular vessels

IV Laceration of segmental or hilar vessels that produces major devascularization >25% of spleen

V Completely shattered spleen; vascular hilar injury with devascularized spleen

Advance 1 grade for multiple injuries up to Grade III

Case: Trauma.

Dx: Grade III splenic injury

Grade III:

Subcapsular hematoma

>50% surface or expanding

Ruptured subcapsular or

intraparenchymal

hematoma.

Hematoma > 5cm

Laceration > 3cm in depth

Case:

Pain.

Dx: Free subdiaphragmatic air

Case: Abdominal pain.

What next?

Case: cont’d

Dx: BAD things: portal venous gas,

pneumatosis, bowel infarction.

Case: Trauma.

Dx: Grade IV injury

AAST Renal Injury Grading

I Contusion or nonexpanding subcapsular hematoma without parenchymal

laceration

II Nonexpanding perirenal hematoma confined to the retroperitoneum Lacerations <1 cm depth in the renal cortex

III Lacerations >1 cm depth without extension into the collecting system or

urinary extravasation

IV Lacerations extending through the renal cortex, medulla, and collecting system

Injuries to the main renal artery or vein with contained hemorrhage

V Completely shattered kidney Injuries to the renal hilum with devascularization of the kidney: traumatic

renal arterial disruption, traumatic renal arterial occlusion

(Advance one grade for bilateral injuries, up to Grade III)

Blunt Renal Injury:

10% of all blunt abdominal injuries involve kidneys.

Mechanism:

MVA

Direct blow

Fall

Grand majority of these are minor injuries

70-85% are Grade I

Contrast-enhanced MDCT is imaging modality of choice

Blunt Renal Injury:

Management:

Conservative management is the rule!

Grade I and II: Watch

Grade III and IV: Controversial. When in doubt, watch.

Nephrectomy rate is higher in patients who undergo operative

exploration (35%) versus those who have conservative management (12%)

Intervention: Main renal artery/vein and UPJ injuries

Active arterial bleeding & devascularization

Urinary extravasation

Case: Trauma

Dx: Grade II renal injury:

Grade I:

Subcapsular hematoma

Contusion

Grade II:

Perinephric hematoma

Laceration < 1cm

Grade III:

Laceration > 1cm

NO collecting system injury

Case: Trauma

Dx: Grade IV-V renal injury

Grade IV: Laceration involving cortex,

medulla, and collecting system.

Segmental infarctions

Main renal artery/vein injuries with contained hematoma.

Grade V: Shattered kidney

UPJ avulsion

Main renal artery/vein avulsion with devascularization

Management?

Active Contrast Extravasation

Arterial injury:

Active extravasation with free spill of contrast: focal high

attenuation jet (matches arteries in density) that fades into an

enlarged, enhanced hematoma on delayed imaging.

Pseudoaneurysm: defined collection, often round, that becomes

less apparent on delayed imaging. No change in hematoma.

Active Contrast Extravasation

Differentiate from:

Bone fragments: unusual shapes, high attenuation on all

imaging.

Venous injury: initial nonvisualization, which becomes more

apparent on delayed imaging.

Caution.

Density of blood:

Simple free fluid: 0-15 HU

Unclotted blood: 20-40 HU

Clotted blood / hematoma: 40-70 HU

Active extravasation: matches origin vessel

Usually within 10 HU

Case: Pain.

Dx: Free subdiaphragmatic air

Dx: Acute cholecystitis.

Case: RUQ pain

Additional imaging

Additional imaging:

Dx: Normal Gallbladder

Case 18: abdominal pain


Case: later that day…

Dx: Acute Cholecystitis

Case: Trauma

Dx: Grade III pancreatic injury

AAST Pancreatic Injury Grading

I Minor contusion without ductal injury

Superficial laceration without ductal injury

II Major contusion without ductal injury

Major laceration without ductal injury

III Distal transection or parenchymal injury with ductal laceration

IV Proximal transection or parenchymal injury involving the ampulla

V Massive disruption of the pancreatic head

*proximal: to the right of the SMV

Blunt pancreatic injury:

Rare (<2% of abdominal injuries)

Mechanism:

MVA

Direct blow

Rare isolated injury

Usually multiple concomitant intra-abdominal injuries.

Associated with relatively high morbidity and mortality

Usually from non-pancreatic causes

Blunt pancreatic injury:

Late or missed diagnosis can result in significant morbidity (or death)

Mortality if diagnosed early (<24hrs): 11%

Mortality if diagnosed late (>24hrs): 40%

Complications:

Pancreatitis

Pseudocyst

Fistula formation

Abscess

Sepsis

Detection of Pancreatic Injury

Overall CT sensitivity in detecting all grades of pancreatic injury is approx. 80%

Accuracy of detecting ductal injury may be as low as 40%

CT may be normal in the first 12 hrs. after injury in 20-40% of patients

Serum amylase levels drawn within 3 hrs. of injury are unreliable

Management of Pancreatic Injury

Grade I and II injuries best treated with hemostasis +/- external drainage

Grade III injuries treated with distal pancreatectomy

Grade IV and V injuries treated with surgery (Whipple)

Case: Trauma

Dx: Grade III pancreatic injury

Grade I: superficial laceration

Duct intact

Grade II: major laceration

Duct intact

Grade III: distal transection

Duct injury

Grade IV: Proximal

transection

Involves ampulla or bile duct

Grade V: Massive disruption

of pancreatic head.

Post-therapy follow-up:

The End.

abdominal emergency cases

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