Abdominal Trauma, Imaging

Abdominal Trauma, Imaging

Description

This is a diagnostic procedure; basis for its use will vary with results of examination.

Diagnosis
Signs and Symptoms

• Abdominal trauma may present in an unstable patient with multiple associated injuries or as an isolated injury in a stable patient with no physical findings.
• Assessment of the abdomen focuses on the need for early surgical management; the diagnosis of specific organ injuries should be handled later.

History

• History should include mechanism of injury, restraint use and type, airbag or helmet use, prehospital vital signs, initial mental status and change in mental status, and any prehospital treatments performed and their effect on patient status.
• AMPLE history (allergies, especially to radiographic contrast agents, medications, past medical history, last meal, events leading up to the injury)

Physical Exam

• Comprehensive physical exam should include complete bodily exposure and perineal and digital rectal exams.
• Abdominal stab wounds should be locally explored after local anesthesia; penetration of the abdominal wall fascia requires further evaluation.
• Caution should be taken because the physical exam is accurate in determining serious abdominal injury in only 45–50% of cases.

Essential Workup

• See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating)

Tests

General approach to imaging in blunt abdominal trauma:

• The ideal abdominal imaging study is rapid, inexpensive, sensitive for operative injury; identifies many nonoperative injuries requiring close observation and follow-up; requires minimal training to perform and interpret; and does not exist yet.
• Ultrasound has become the initial screening test of choice for hemodynamically stable patients; it has replaced diagnostic peritoneal lavage in many clinical settings.
• CT scan is the definitive test for most patients, especially children, but requires intravenous contrast material:
• Unstable patients should not be transported for a CT scan.
• Most patients require serial physical examinations and a period of observation even after negative imaging studies.

Imaging

Ultrasound

• Advantages:
• Rapid
• Noninvasive
• Can be performed at patient's bedside
• Does not require contrast agents or ionizing radiation
• Disadvantages:
• Operator dependent
• Does not reliably identify specific organ injury
• Not sensitive enough to exclude all injuries. Serial examination and observation are required if ultrasound is the sole imaging study.
• Is not well suited for penetrating injuries; may miss significant bowel injuries not accompanied by hemoperitoneum
• Does not evaluate spinal or retroperitoneal injuries
• Indications:
• Blunt trauma in either stable or unstable patients
• Contraindications:
• Absolute:
• Pre-existing indication for exploratory laparotomy
• Relative:
• Obesity
• Subcutaneous emphysema
• Positive test:
• Demonstration of free fluid or obvious solid organ injury (approximately 250 mL free fluid required in adults)
• Adequate exam includes visualization of Morrison pouch, pericardium, both paracolic gutters, and the pelvic rectouterine pouch (pouch of Douglas), and exam of the liver and spleen for parenchymal injuries.
• Considerations:
• Positive test result should be followed by CT in a stable patient or by laparotomy in an unstable patient.
• Institutional factors determine which clinical department performs the study.

CT scan:

• Advantages:
• Sensitivity of 85–98%
• Provides specific organ injury information
• Allows for simultaneous reformatting and reconstruction of spinal structures
• Fosters nonoperative approach to solid organ injuries
• Diagnoses retroperitoneal and bony injuries missed by other modalities.
• Disadvantages:
• Requires intravenous contrast (acute contrast reactions and renal failure)
• Isolated diaphragmatic, pancreatic, bowel injuries may be missed, especially if performed immediately after injury.
• Indications:
• Hemodynamically stable patients
• Contraindications:
• Absolute:
• Pre-existing indication for exploratory laparotomy
• Hemodynamic instability
• Previous contrast reaction
• Relative:
• Multiple allergies
• Considerations:
• Modality of choice in children
• Many multiple-injury patients require CT imaging of the head, spine, chest, or pelvis; modern equipment provides for rapid scanning of multiple anatomic regions in one session.
• Monitoring must be continued in the CT suite; patients should be accompanied by appropriate medical personnel.
• Water may be substituted for oral contrast, but optimal detection of intestinal injury requires oral contrast and a 2- to 4-hour delay for intestinal opacification.

Diagnostic Procedures/Surgery

• Gunshot wounds to the abdomen require evaluation by a surgeon and will require laparotomy:
• Selective laparotomy is an option for experienced centers.
• Diagnostic peritoneal lavage:
• Advantages:
• Rapid
• Relatively simple to perform
• 97.8% accurate in diagnosing injury
• Disadvantages:
• Invasive
• Does not identify specific organ injury
• 1–2% complication rate
• May miss retroperitoneal injuries and intraperitoneal bladder rupture
• Indications:
• Hemodynamically unstable patients
• Patients requiring emergent surgery for other conditions (e.g., craniotomy for epidural hematoma)
• Stab wounds that penetrate the abdominal fascia
• Contraindications:
• Absolute: pre-existing indication for exploratory laparotomy
• Relative: previous abdominal surgery, severe abdominal distention, pregnancy, pediatric patients
• Nasogastric tube and Foley catheter placement mandatory before beginning procedure
• Positive test:
• Aspiration of >10 mL of blood, bile, bowel contents, or urine
• Diagnostic peritoneal lavage fluid in the urine or chest tube
• Blunt trauma with >100,000 erythrocytes/mm³
• Penetrating trauma >1,000 erythrocytes/mm³
• Considerations:
• Favored in stab wound patients when local wound exploration is confirmatory
• Favored in unstable blunt trauma patients because it may be performed simultaneously with other emergency-basis surgical interventions (e.g., craniotomy for epidural hematoma)
• Must always be accompanied by serial abdominal exams after procedure
• In the presence of pelvic fractures, use supraumbilical location.
• In pregnancy, consider supraumbilical or open technique.
• False-positive results may be obtained if performed >8 hours after injury.

Differential Diagnosis

See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating).

Treatment

Pre Hospital

All patients with a significant mechanism of injury or suspicion of major trauma should be triaged to a facility equipped to manage such injury.

Pediatric Considerations

• Pediatric patients should be triaged to a pediatric trauma center or to an adult trauma center equipped to manage children.
• CT scan should be considered the diagnostic test of choice in children as a greater percentage of injuries in children will be managed nonoperatively.
• Diagnostic peritoneal lavage (DPL) is relatively contraindicated.

Initial Stabilization

• In unstable patients, management of the airway, breathing, and circulation; treatment of hypovolemic shock; and control of major hemorrhage must take precedence.
• See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating).

ED Treatment

See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating).

Follow-Up

Disposition

Admission Criteria

See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating).

Discharge Criteria

See Abdominal Trauma (Blunt) and Abdominal Trauma (Penetrating).

References
1. Amoroso TA. Evaluation of the patient with blunt abdominal trauma: an evidence based approach. Emerg Med Clin North Am. 1999;17-75.
2. Chiquito PE. Blunt abdominal injuries. Diagnostic peritoneal lavage, ultrasonography and computed tomography scanning. Injury. 1996;27:117-124.
3. Pryor JP, Reilly PM, Dabrowski GP, et al. Nonoperative management of abdominal gunshot wounds. Ann Emerg Med. 2004;43(3):344-353.
4. Rose JS. Ultrasound in abdominal trauma. Emerg Med Clin North Am. 2004;22(3):581-599.
5. Stengel D, Bauwens K, Sehouli J, et al. Emergency ultrasound-based algorithms for diagnosing blunt abdominal trauma. Cochrane Database Syst Rev. 2005;18(2):cd004446.

Miscellaneous
SEE ALSO: Abdominal Trauma, Blunt; Abdominal Trauma, Penetrating
Codes
N/A

Abdominal Trauma, Blunt

Abdominal Trauma, Blunt

Description

· Injury results from a sudden increase of pressure to abdomen.

• Solid organ injury usually manifests as hemorrhage.
• Hollow viscous injuries result in bleeding and peritonitis from contamination with bowel contents.

Etiology

• Sixty percent result from motor vehicle collisions.
• Solid organs are injured more frequently than hollow viscous organs.
• The spleen is the most frequently injured organ (25%), followed by the liver (15%), intestines (15%), retroperitoneal structures (13%), and kidney (12%).
• Less frequently injured are the mesentery, pancreas, diaphragm, urinary bladder, urethra, and vascular structures.

Pediatric Considerations

• Children tend to tolerate trauma better because of the more elastic nature of their tissues.
• Owing to the smaller size of the intrathoracic abdomen, the spleen and liver are more exposed to injury because they lie partially outside the bony rib cage.

Diagnosis

Signs and Symptoms

• Spectrum from abdominal pain, signs of peritoneal irritation, to hypovolemic shock
• Nausea or vomiting
• Labored respiration from diaphragm irritation or upper abdominal injury
• Left shoulder pain with inspiration (Kehr sign) from diaphragmatic irritation owing to bleeding
• Delayed presentation possible with small bowel injury

Essential Workup

• Evaluate and stabilize airway, breathing, and circulation (ABCs).
• Primary objective is to determine need for operative intervention.
• Examine abdomen to detect signs of intra-abdominal bleeding or peritoneal irritation.
• Injury in the retroperitoneal space or intrathoracic abdomen is difficult to assess by palpation.
• Remember that the limits of the abdomen include the diaphragm superiorly (nipples anteriorly, inferior scapular tip posteriorly) and the intragluteal fold inferiorly and encompass entire circumference.
• Abrasions or ecchymoses may be indicators of intra-abdominal injury:
• Roll the patient to assess the back.
• Bowel sounds may be absent from peritoneal irritation (late finding).
• Foley catheter (if no blood at the meatus, no perineal hematoma, and normal prostate exam) to obtain urine and record urinary output
• Plain film of the pelvis:
• Fracture of the pelvis and gross hematuria may indicate genitourinary injury.
• Further evaluation of these structures with retrograde urethrogram, cystogram, or intravenous pyelogram
• CT most useful in assessing need for operative intervention and for evaluating the retroperitoneal space and solid organs:
• Patient must be stable enough to make trip to scanner.
• Also useful for suspected renal injury
• FAST (focused abdominal sonography for trauma) to detect intraperitoneal fluid
• Ultrasonography is rapid, requires no contrast agents, and is noninvasive.
• Operator dependent
• Diagnostic peritoneal lavage (useful for revealing injuries in the intrathoracic abdomen, pelvic abdomen, and true abdomen) primarily indicated for unstable patients:
• Positive with gross blood, RBC count of >100,000/mm³, WBC count of 500/mm³, or presence of bile, feces, or food particles

Tests

Lab

• Hemoglobin/hematocrit, which initially may be normal owing to isovolemic blood loss
• Type and cross is essential.
• Urinalysis for blood:
• Microscopic hematuria in the presence of shock is an indication for genitourinary evaluation.
• Arterial blood gases:
• Base deficit may suggest hypovolemic shock and help guide the resuscitation.

Imaging
See Essential Workup.

Diagnostic Procedures/Surgery
See Essential Workup.

Differential Diagnosis
Lower thoracic injury may cause abdominal pain.

Treatment

Pre Hospital

• Aggressive fluid resuscitation is still considered standard of care.
• Normal vital signs do not preclude significant intra-abdominal pathology.

Initial Stabilization

• Ensure adequate airway:
• Intubate if needed.
• O₂ 100% by nonrebreather face mask
• Two large-bore intravenous lines with crystalloid infusion
• Begin infusion of packed RBCs if no response to 2 L of crystalloid.
• If patient is in profound shock, consider transfusion of O-negative or type-specific blood.

ED Treatment

• Continue stabilization begun in field.
• Nasogastric tube to evacuate stomach, decrease distention, and decrease risk of aspiration:
• May relieve respiratory distress if caused by a herniated stomach through the diaphragm

Medication (Drugs)

• Tetanus toxoid booster: 0.5 mL IM for patients with open wounds
• Tetanus immune globulin: 250 units IM for patients who have not had complete series
• Intravenous antibiotics: broad-spectrum aerobic with anaerobic coverage such as a second-generation cephalosporin

Pediatric Considerations

• Crystalloid infusion is 20 mL/kg if patient in shock.
• Packed RBC dose is 1 mL/kg.

Follow-Up
Disposition

Admission Criteria

• Postoperative cases
• Equivocal findings on diagnostic peritoneal lavage, FAST exam, or CT
• Many blunt abdominal trauma patient benefit from admission, monitoring, and serial abdominal examinations.

Discharge Criteria

No patient in whom you suspect intra-abdominal injury should be discharged home without an appropriate period of observation despite negative examination or imaging studies.

References
1. Amoroso TA. Evaluation of the patient with blunt abdominal trauma: an evidence based approach. Emerg Med Clin North Am. 1999;17:63-75.
2. Brasel KJ, et al. Incidence and significance of free fluid on abdominal CT in blunt trauma. J Trauma. 1995;44(5):889-892.
3. Davis JJ, Cohn I Jr, Nance FC. Diagnosis and management of blunt abdominal trauma. Ann Surg. 1976;183:672-678.
4. Holmes JF, et al. Performance of helical CT without oral contrast for the detection of gastrointestinal injuries. Ann Emerg Med. 2004;43(1):120-128.
5. McGahan JP, Wang L, Richards JR. Focused abdominal ultrasound for trauma. Radiographics. 2001;21:91-99.
6. Stengel D, Bauwens K, Sehouli J, et al. Systematic review and meta-analysis of emergency ultrasonography for blunt abdominal trauma. Br J Surg. 2001;88:901-912.

Codes
ICD9-CM
868.00
ICD10
S39.9

Abdominal Pain

Abdominal Pain

Description

• Parietal pain:
• Irritating material causing peritoneal inflammation
• Pain transmitted by somatic nerves
• Exacerbated by changes in tension of the peritoneum
• Pain characteristics:
• Sharp
• Well localized
• Abdominal tenderness
• Involuntary guarding
• Rebound tenderness
• Exacerbated by movement and coughing
• Visceral pain:
• Distention of a viscous or organ capsule or spasm of intestinal muscularis fibers:
• Pain is generally poorly localized.
• Colicky with intestinal distention
• Constant with a distended gallbladder or kidney
• Inflammation:
• Initially, the pain is poorly localized.
• Focal tenderness develops as the inflammation extends to the peritoneum or localizers.
• Ischemia from vascular disturbances:
• Pain is severe and diffuse with catastrophic vascular emergencies
• Pain is disproportional to the abdominal examination
• Referred pain:
• Felt at distant location from diseased organ
• Due to an overlapping supply by the affected neurosegment to the perceived location of pain
• Abdominal wall pain:
• Constant
• Aching
• Muscle spasm
• Involvement of other muscle groups

Etiology

• Peritoneal irritants:
• Gastric juice
• Fecal material
• Pus
• Blood
• Bile
• Pancreatic enzymes
• Visceral obstruction:
• Small intestines
• Large intestines
• Gallbladder
• Ureters and kidneys
• Visceral ischemia
• Intestinal
• Renal
• Splenic
• Visceral inflammation:
• Appendicitis
• Inflammatory bowel disorders
• Cholecystitis
• Hepatitis
• Peptic ulcer disease
• Pancreatitis
• Pelvic inflammatory disease
• Pyelonephritis
• Abdominal wall pain
• Referred pain:
• The possibility of intrathoracic disease must be considered in every patient with abdominal pain.

Diagnosis

Signs and Symptoms

• General:
• Anorexia
• Malaise
• Tachycardia
• Hypotension
• Fever
• Nausea
• Vomiting:
• Etiology requiring surgical intervention is less likely when vomiting precedes the onset of pain
• Abdominal:
• Diarrhea
• Constipation
• Distended abdomen
• Abnormal bowel sounds:
• High-pitched rushes with bowel obstruction
• Absence of sound with ileus or peritonitis
• Often unreliable
• Pulsatile abdominal mass
• Rovsing sign:
• Palpation of left lower quadrant causes pain in right lower quadrant (RLQ)
• Suggestive of appendicitis
• McBurney point tenderness associated with appendicitis:
• Palpation in RLQ two-thirds distance between umbilicus and right anterior superior iliac crest causes pain
• Murphy sign:
• Pause in inspiration while examiner is palpating under liver
• Suggestive of cholecystitis
• Psoas sign:
• Pain on extension of the thigh
• Suggests inflammation around psoas muscle
• Obturator sign
• Pain on rotation of the flexed thigh, especially internal rotation
• Inflammation around internal obturator muscle
• Tender or discolored hernia site
• Rectal and pelvic examination:
• Tenderness with pelvic peritoneal irritation
• Cervical motion tenderness
• Adnexal masses
• Rectal mass or tenderness
• Genitourinary:
• Flank pain
• Dysuria
• Hematuria
• Vaginal bleeding
• Tender adnexal mass on pelvis
• Testicular pain
• May be referred from renal or appendiceal pathology
• Testicular swelling
• High-riding testes
• Transverse lie of testis
• Extremities:
• Shoulder pain:
• Referred pain from diaphragmatic involvement
• Pulse deficit or unequal femoral pulses
• Skin:
• Jaundice
• Herpes zoster
• Cellulitis

Essential Workup

Historical characteristics define the type of pain and suggest underlying causes:

• Nature of onset of pain
• Time of onset and duration of pain
• Location of pain initially and at presentation
• Extra-abdominal radiations
• Quality of pain (e.g., sharp, dull, crampy)
• Palliative or provocative factors
• Relation of associated finding to onset of pain
• Changes in bowel habits
• History of trauma
• Gynecologic history
• Visceral obstruction

Tests

Lab

• CBC:
• WBC is a poor predictor of surgical disease
• Urinalysis
• Serum lipase:
• More accurate than a serum amylase in diagnosing pancreatic disorders
• hCG
• Serum electrolytes and glucose
• Liver function tests
• Gonorrhea and chlamydia cultures should be obtained if a pelvic examination is performed.

Imaging

• ECG:
• Indicated in patients with epigastric pain with risk factors for coronary artery disease
• Kidney, ureter, and bladder (KUB) and upright:
• Indicated primarily if bowel obstruction is suspected
• Air-fluid levels and intestinal distention:
• Bowel obstruction
• Ileus
• Volvulus
• Intussusception
• Upright chest radiograph:
• Pneumoperitoneum
• Perforated viscus
• Extra-abdominal causes
• Ultrasound:
• Biliary abnormalities
• Hydronephrosis
• Intraperitoneal fluid
• Aortic aneurysm
• Pelvic ultrasound

• Abdominal CT:
• Spiral CT without contrast:
• Determines location and size of stone in patients with renal colic
• CT with IV contrast only:
• Vascular rupture suspected in a stable patient
• CT with IV and oral contrast:
• Indicated when there is a suspicion of a surgical etiology involving bowel or intraperitoneal hemorrhage
• CT with rectal contrast only:
• High accuracy reported in detecting appendicitis
• IVP:
• Indicated in patients with suspected ureteral calculi
• More time-consuming than spiral CT
• Barium enema:
• Intussusception
• Volvulus

Differential Diagnosis

• Parietal pain:
• Abdominal arterial aneurysm
• Appendicitis
• Diverticulitis with perforation or abscess
• Ruptured ectopic pregnancy
• Ruptured ovarian cyst
• Pancreatitis
• Perforated peptic ulcer
• Perforated viscus
• Splenic rupture
• Visceral pain:
• Abdominal epilepsy
• Abdominal migraine
• Adrenal crisis
• Early Appendicitis
• Bowel obstruction
• Cholecystitis
• Constipation
• Depression
• Diabetic ketoacidosis
• Diverticulitis
• Dysmenorrhea
• Ectopic pregnancy
• Esophagitis
• Fecal impaction
• Fitz-Hugh–Curtis syndrome
• Gastroenteritis
• Hepatitis
• Hirschsprung disease
• Incarcerated hernia
• Inflammatory bowel disease
• Intussusception
• Irritable bowel syndrome
• Ischemic bowel
• Lactose intolerance
• Lead poisoning
• Meckel diverticulitis
• Neoplasm
• Ovarian torsion
• Pancreatitis
• Pelvic inflammatory disease
• Peptic ulcer disease
• Renal/ureteral calculi
• Sickle cell crisis
• Splenic infarction
• Spontaneous abortion
• Testicular torsion
• Urinary tract infection
• Volvulus
• Referred pain:
• Myocardial infarction
• Pneumonia
• Abdominal wall pain:
• Abdominal wall hematoma or infection
• Black widow spider bite
• Herpes zoster

Pediatric Considerations

• <2>
• Hirschsprung disease
• Incarcerated hernia
• Intussusception
• Neoplasm
• Sickle cell crisis
• Volvulus
• 2-5 years:
• Appendicitis
• Incarcerated hernia
• Meckel diverticulitis
• Neoplasm
• Sickle cell crisis
• >5 years:
• Appendicitis
• Ectopic pregnancy
• Inflammatory bowel disease
• Pelvic inflammatory disease

Treatment

Initial Stabilization

• Emergent laparotomy:
• Patients who are hemodynamically unstable with suspected vascular rupture
• IV fluids

ED Treatment

• Antiemetics are important for comfort.
• Narcotics or analgesics should not be withheld.
• Antibiotics are needed in potential perforation and in peritonitis.
• Surgical consultation based on suspected etiology

Medication (Drugs)

• Ampicillin: 0.5-2 g IV
• Cefotetan 1-2 g IV
• Cefoxitin: 1-2 g IV
• Compazine 5-10 mg PO prn nausea
• Gentamicin: 1-1.7 mg/kg IV
• Levofloxacin: 500 mg IV
• Metronidazole 15mg/kg IV, loading dose
• Ondansetron 4 mg IV prn nausea
• Promethazine: 12.5-25 mg PO/IM/IV

Follow-Up

Disposition

Admission Criteria

• Surgical intervention
• Peritoneal signs
• Patient unable to keep down fluids
• Lack of pain control
• Medical cause necessitating in-house treatment (myocardial infarction, diabetic ketoacidosis)
• IV antibiotics needed

Discharge Criteria

No surgical or severe medical etiology found in patient who is able to keep fluid down, has good pain control, and is able to follow detailed discharge instructions.

References
1. Graff LG 4th, Robinson D. Abdominal pain and emergency department evaluation. Emerg Med Clin North Am. 2001;19(1):123-136.
2. Hendrickson M, Naparst TR. Abdominal surgical emergencies in the elderly. Emerg Med Clin North Am. 2003;21(4):937-969.
3. Kamin RA, Nowicki TA, Courtney DS, Powers RD. Pearls and pitfalls in the emergency department evaluation of abdominal pain. Emerg Med Clin North Am. 2003;21(1):61-72
4. Kizer KW, Vassar MJ. Emergency department diagnosis of abdominal disorders in the elderly. Am J Emerg Med. 1998;16(4):357-362.
5. Mason JD. The evaluation of acute abdominal pain in children. Emerg Med Clin North Am. 1996;14(3):629-643.

Codes
ICD9-CM
789.0
ICD10
R10.4