Blunt Trauma: what do we miss/how can we improve?

Authors: Carling Macdonald¹, Anthony Scoccimarro, MD², and Muhammad Waseem, MD, MS² (St. Georges University Grenada West Indies¹; Lincoln Medical & Mental Health Center Bronx, New York²) // Edited by Edited by: Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UTSW / Parkland Memorial Hospital) and Stephen Alerhand, MD (@SAlerhand, EM Resident Physician, Icahn School of Medicine at Mount Sinai)

Missed injuries are fortunately rare, yet the injured trauma patient may present a unique diagnostic challenge. Missed injuries and delay in diagnosis remain a concern for ED physicians caring for trauma patients. Delayed diagnosis of intra-abdominal injuries, for instance, results in significantly increased morbidity and mortality. Literature suggests an 8.1% incidence of patients with missed injuries, which may be an underestimation of the true incidence of missed injuries.[i]

Evaluation of Blunt Trauma

• Stabilization and identification of life-threatening injuries
• Physical examination
  • Primary survey
    • Primary goal: identify and prioritize the most life-threatening injuries
    • Includes: Airway, Breathing, Circulation, Disability, Exposure
  • Secondary Survey
    • Identify and address all other injuries
  • Diagnostic testing options
    • Bedside ultrasound (FAST examination)
      The focused assessment with sonography in trauma (FAST) examination for the evaluation of injured patients is not sensitive enough to exclude all intra-abdominal injuries. Patients with small amounts of free fluid may have false-negative FAST examination.[ii]
    • CT scan
      Should be obtained only in hemodynamically stable patients in whom there is no apparent indication for an emergent laparotomy.
    • Potential useful laboratory tests
      • CBC, CMP, lipase, UA
        • Laboratory evaluation is generally of limited value and should be considered as an adjunct to the clinical assessment.

What body parts are at higher risk for missed injuries?

The most commonly involved body region of missed injuries was the head/neck, followed by the chest and extremities.[iii]

Spine[iv],[v]
Abdomen[vi]^,[vii],[viii]
Extremities[ix]

What are commonly missed injuries in blunt trauma?

• Rib fractures
• C-spine injuries in elderly[x]
• Spleen and liver (especially if an initial FAST examination is negative)
  

How do we miss?

• Multiple injuries, or distracting injuries, potentially unavoidable factors such as other life-threatening injuries and severe head injuries. In one study, 9% of patients with multiple injuries sustained injuries that were not discovered during the primary and secondary surveys.[xi] Certain factors such as a younger age, more severe injury, poly-trauma, and the absence of soft-tissue injuries are significantly associated with missed injuries. In addition, patientswith missed injuries may have lower Glasgow Coma Scale scores and may have required pharmacologic paralysis. CT may miss gastrointestinal, diaphragmatic, and pancreatic injuries.
• Inadequate or incomplete clinical assessment
• Hemodynamic instability
• Radiological misinterpretation
• False-negative FAST examination
  • The FAST examination for the evaluation of injured patients is NOT sensitive enough to exclude all abdominal injuries.
  • The FAST examination is not designed to reliably detect injuries to the solid organs, intestine, mesentery, diaphragm, or the retroperitoneal area (often associated with pelvic fractures).
  • Volumes less than 400 mL in RUQ have been hard to distinguish.
  • Pelvic views are limited if the bladder is empty or there is a Foley placed
  • Delayed presentation: free fluid remains anechoic until it begins to clot and difficult to differentiate from the surrounding tissue.[xii]
• Over-reliance on the physical examination: clinical examination as a screening tool for evaluation of thoracolumbar spine injuries is inadequate. In a study, physical examination missed 6.9% of all fractures and 15.4% of those that were clinically significant. The sensitivity and specificity of clinical examination for TL spine fractures were 48.2% and 84.9%, respectively, for all fractures and 78.6% and 83.4% for those that were clinically significant.[xiii]

Does non-operative management increase risk for missed injuries?

With increasing rates of non-operative management, there has been concern that these associated injuries may become missed injuries. Data suggest that missed injury is more common in conjunction with liver (2.3%) rather than splenic injury with increased rate of bowel and pancreatic injuries. It may be that more force is needed to injure the liver as compared with the spleen.[xiv]

How do we improve?

• Obvious clinical signs of trauma, such as abdominal distension or hematoma should prompt careful physical examination.
• The absence of abdominal pain or tenderness on physical examination does not rule out significant abdominal injury
• In the absence of hepatic or splenic injuries, the presence of free fluid in the abdominal cavity may suggest an injury to gastrointestinal tract or its mesentery.
• When attempting to avoid a false-negative FAST examination, one can repeat the exam at regular intervals. This is especially warranted if the clinical status changes and this approach can be used to increase the sensitivity of the examination.
• Look for common physical examination patterns that are associated with intra-abdominal injury caused by blunt trauma:
  • Lap belt marks
  • Steering wheel contusions
  • Abdominal distension
  • Abdominal guarding
  • Hypotension
  • Rebound tenderness
  • Concomitant femur fracture

• Established well-thought-out protocol helps to organize the resuscitation and assessment of the trauma patient and minimize the chance of missed injury.
• The ATLS course of the American College of Surgeons defines two surveys for the trauma patient: the primary survey, which is designed to identify all immediately life-threatening injuries within minutes of arrival and to treat those injuries in the emergency department as they are discovered; and a secondary survey, which is designed to be a “head-to-toe” search for all other injuries the patient has sustained. Know this cold, however be able to step outside of it when the patient in front of you requires it. Go here for further discussion: http://www.emdocs.net/traumatic-cardiac-arrest/
• The tertiary trauma survey is very important as majority of clinically significant missed injuries are detected by tertiary trauma survey. This survey should be standardized which may result in a decrease in missed injuries.[xv] The following should be included:
  • Re-evaluation of laboratory tests obtained
  • Review of initial radiographs obtained
  • Assessment for the effective detection of occult injuries

Take-home points/Pearls

• Some missed injuries may be due to inadequate clinical assessment; therefore an accurate assessment is very critical to identify injuries.
• A false negative FAST examination is NOT sensitive enough to rule out all abdominal injuries.
• The absence of abdominal pain or tenderness does not rule out significant injury.
• Following ATLS protocol may be helpful for an adequate assessment.

Go here for further reading related to this topic: http://www.emdocs.net/the-cleared-trauma-patient-what-could-we-be-missing/

References / Further Reading

[i] Buduhan G, McRitchie DI. Missed injuries in patients with multiple trauma. J Trauma. 2000 Oct;49(4):600-605

[ii] Laselle BT, Byyny RL, Haukoos JS, Krzyzaniak SM, Brooks J, Dalton TR, Gravitz CS, Kendall JL. False-negative FAST examination: associations with injury characteristics and patient outcomes. Ann Emerg Med. 2012 Sep;60(3):326-34.e3

[iii] Chen CW, Chu CM, Yu WY, Lou YT, Lin MR. Incidence rate and risk factors of missed injuries in major trauma patients. Accid Anal Prev. 2011 May;43(3):823-8

[iv] Anderson S, Biros MH, Reardon RF. Delayed diagnosis of thoracolumbar fractures in multiple-trauma patients. Acad Emerg Med.1996;3:832-839

[v] Ryan M, Klein S, Bongard F. Missed injuries associated with spinal cord trauma. Am Surg.1993;59:371-374

[vi] Wisner DH, Victor NS, Holcroft JW. Priorities in the management of multiple trauma: intracranial versus intra-abdominal injury. J Trauma.1993;35:271-276

[vii] Onuora VC, Patil MG, Al-Jasser AN. Missed urological injuries in children with polytrauma.Injury.1993;24:619-621

[viii] Sung CK, Kim KH. Missed injuries in abdominal trauma. J Trauma. 1996;41:276-278

[ix] Ward WG, Nunley JA. Occult orthopaedic trauma in the multiple injured patient. J Orthop Trauma.1991;5:308-312

[x] Goode T, Young A, Wilson SP, Katzen J, Wolfe LG, Duane TM. Evaluation of cervical spine fracture in the elderly: can we trust our physical examination? Am Surg. 2014 Feb;80(2):182-184

[xi] Enderson BL, Reath DB, Meadors J, Dallas W, DeBoo JM, Maull KI. The tertiary trauma survey: a prospective study of missed injury. J Trauma.1990; 30:666-669

[xii] Williams SR, Perera P, Gharahbaghian L. The FAST and E FAST in 2013: trauma ultrasonography: overview, practical techniques, controversies, and new frontiers. Crit Care Clin. 2014 Jan;30(1):119-150

[xiii] Inaba K, DuBose JJ, Barmparas G, Barbarino R, Reddy S, Talving P, Lam L, Demetriades D. Clinical examination is insufficient to rule out thoracolumbar spine injuries. J Trauma. 2011 Jan;70(1):174-179

[xiv] Miller PR, Croce MA, Bee TK, Malhotra AK, Fabian TC. Associated injuries in blunt solid organ trauma: implications for missed injury in non-operative management. J Trauma. 2002 Aug;53(2):238-242

[xv] Pfeifer R, Pape HC. Missed injuries in trauma patients: A literature review. Patient Saf Surg. 2008 Aug 23;2:20