Background
The past couple of decades have seen increased access to and ease of using CT scanning for traumatically injured patients. Given that the abdomen is an important source of occult bleeding, routine use of abdominal CT scans has become increasingly common and has predictably yielded many negative studies as well as finding clinically irrelevant abnormalities. Select use (rather than routine use) of abdominal CT scans has been shown to be effective in identifying abdominal injuries, but the presence of distracting injuries is thought to negate the utility of the clinical examination.
Clinical Question
How accurate is the clinical abdominal examination in predicting or excluding the presence of intraabdominal trauma in patients with distracting injuries?
Population
All hemodynamically stable blunt trauma activation patients in a single center (the University of South Alabama Trauma Center) over the course of one year. Patient included were older than 13 years old with a GGS of 14 or 15 who sustained blunt trauma. No patients were excluded on basis of intoxication or number/severity of distracting injuries.
Intervention
Patients underwent abdominal CT scanning routinely, as prior to the study. However, before the CT scan was performed, the surgery resident or attending documented the abdominal exam, specifically “positive” versus “negative” for their concern for intraabdominal injuries. Distracting injuries were also recorded for each patient. Then routine abdominal CTs were performed.
The definition of distracting injuries used in this paper came from a 2012 study regarding c-spine clearance in distracting injuries (Rose 2012). They were divided into head injuries, torso injuries, and long bone fractures. Head injuries included skull fracture, >2 facial fractures, mandible fracture, and intracranial bleeding. Torso injuries included >2 rib fractures and clavicle, scapula, sterum, pelvis, and thoracolumbar spine fractures. Long bones included were femur, tibia/fibula, humerus, radius/ulna fractures and hip/shoulder dislocations.
Outcomes
Sensitivity and specificity of abdominal examination for surgically significant and transfusion-requiring abdominal injuries in alert trauma patients with and without distracting injuries.
Design
Prospective observational study
Excluded
Hemodynamically unstable, neurologic deficits, GCS < 14
Primary Results
- 56.2% of trauma patients entered into the study had distracting injuries.
- 49% of the group with distracting injuries had a negative clinical abdominal examination
- 2.3% of this cohort had intraabdominal injuries on CT.
- Abdominal exam was 100% sensitive for surgically significant and transfusion-requiring abdominal injuries in patients with and without distracting injuries
- Missed injuries were solid organ injuries that did not require intervention
- 89.5% sensitivity overall in patients without distracting injuries
- 89.5% sensitivity overall in patients WITH distracting injuries
- Distracting injuries more likely to be correlated with intraabdominal injuries were 2+ rib fractures (50% of patients with intraabdominal injuries), thoracolumbar spine (25%) pelvic (23%) or femur (21%) fractures
- Potential to decrease CT scans in this cohort by 49%
Strengths
- Data was prospectively collected
- There were minimal exclusion criteria making this study more generalizable. In particular, drug and alcohol use were not exclusion criteria
- Injuries and impression of abdominal examination were documented prior to CT scanning
- Potential for enormous savings of resources and money
Limitations
- Single center study limiting external validity
- Study was underpowered and would have needed to enroll 7,000 patients to prove or disprove equivalence of abdominal examination in these patients.
- Examination performed by surgery resident of any level, or attending, not controlling for experience and there was no evaluation of inter-rater reliability
- Unclear if patients were consecutively collected
Author's Conclusions
“Distracting injuries do not seem to diminish the efficacy of clinical abdominal examination for the diagnosis of clinically significant abdominal injury. These data suggest that clinical examination of the abdomen is valid in awake and alert blunt trauma patients, regardless of the presence of other injuries.”
Our Conclusions
This study presents a change in trauma diagnostics and explores the idea of selective abdominal CT scans in hemodynamically stable trauma patients with distracting injuries—or those who are intoxicated—with GCS of 14 or 15. Although some intraabdominal injuries were identified via CT scan in patients with negative abdominal examinations (with and without distracting injuries), none required urgent surgical intervention or transfusion. As many of these patients had other injuries, they were frequently observed in the hospital for a period, increasing the chance of identifying a change in abdominal exam or hemodynamics. This study looked at 800 trauma patients and would have needed 7,000 patients to be sufficiently powered, so at this point it is just “food for thought”.
Potential Impact To Current Practice
Further study is needed to systematically exclude routine abdominal CT scans for trauma patients with distracting injuries, but the routine “pan scan” of trauma patients does deserve more critical assessment.
Bottom Line
Alert trauma patients with negative abdominal examinations—even those who are intoxicated or have distracting injuries—may not require routine abdominal CT scans, as the incidence of intraabdominal injuries in these patients is very low.
Read More
Rose MK et al. Clinical clearance of the cervical spine in patients with distracting injuries: it is time to dispel the myth. J Trauma Acute Care Surg 2012; 73(2): 498-502. PMID: 23019677