You could go ahead and pick out a good book this summer. But why waste time on formulaic plots and slapdash characterizations when you could be reading great articles relevant to the Pediatric Emergency Department. Here’s another paper from the PEMBlog Summer Reading List!
Holmes et al.
Ann Emerg Med. 2013 Aug;62(2):107-116.e2
What this article is about?
This is a multicenter study designed to derive a prediction rule to help identify which children were very low risk for IAI. Holmes et al. prospectively enrolled over 12,000 children with blunt torso trauma, who had an average age of 11 years. 761/12,044 had IAI (6.3%). Of these 761 a little more than a quarter needed one or more of the acute interventions listed below – 203/761 (26.7%);
- Laparotomy
- Angiographic embolization
- Transfusion for intraabdominal hemorrhage
- IV Fluids for ≥2 nights for pancreatic/bowel injuries
Using binary recursive partitioning (a multivariable statistical method used to create decision trees/rules) the authors identified the following factors, in descending order of importance, that were related to children being low risk for IAI requiring acute intervention:
- No evidence of abdominal wall trauma or seat belt sign
- Glasgow Coma Scale score ≥ 13
- No abdominal tenderness
- No evidence of thoracic wall trauma
- No complaints of abdominal pain
- No decreased breath sounds
- No vomiting
Here is the decision rule in graphical form:
Why is it important?
Obviously if you work in a Pediatric Emergency Department or a general ED you will see a child with a blunt belly injury. Understanding who is at risk for intraabdominal injury and who isn’t will save children from unnecessary CT scans. The decision rule seen above has the following statistical characteristics, which you should be aware of:
- Negative predictive value – 99.9% (95%CI 99.7% to 100%)
- Sensitivity – 97%( 95% CI 94% to 99%)
- Specificity – 42.5% (95% CI 41.6% to 43.4%)
- Negative likelihood ratio – 0.07 (95% CI 0.03 to 0.15)
How you can use it in your practice
Knowing why you should be worried about a child with blunt abdominal trauma is the key to making smart and prompt diagnostic and therapeutic decisions. So, here are some key take home points;
- Assessment for blunt IAI is a key part of the secondary survey (after the ABCs)
- Hemodynamically unstable children unresponsive to isotonic IV bolus and blood need a laparotomy.
- Patients with multiple risk factors as noted above who are hemodynamically stable should undergo abdominal/pelvic CT with contrast
- Note that FAST is less helpful diagnostically in children, as hemodynamically stable children with a positive FAST are much more likely need non-operative management as opposed to adults.
- Hemodynamically unstable children (hypotensive, need >40 mL/kg of isotonic fluid) with a positive FAST should undergo diagnostic laparotomy
- Children getting a CT should at least get a CBC and type and screen, ALT and AST.
- Every patient should have a chest X-Ray in the trauma bay to look for pneumothorax and widened mediastinum. If either/both are seen and the patient is stable a chest CT should be considered (after interventions like chest tubes of course).
- Hemodynamically stable with a reassuring exam, but concern for IAI (1 predictor from above like mild abdominal tenderness alone) should undergo lab testing and have serial abdominal exams. The labs include (along with likelihood of IAI if abnormal):
- Hematocrit ≤30% OR 2.6 (95% CI 0.9 to 7.5)
- Urinalysis >5 RBCs/hpf OR 4.8 (95% CI 2.7 to 8.4)
- Transaminases – AST ≥200 U/L or ALT ≥125 U/L OR 17.4 (95% CI 9.4 to 32.1)
- Amylase >125 IU/L and elevated Lipase Much less sensitive than the others, particularly amylase. Lipase in one study has a PPV of 75%
- Other factors associated with elevated odds of IAI should prompt imaging as well. These include:
- Low systolic blood pressure OR 4.1 (95% CI 1.1 to 15.2)
- Femur fracture OR 1.3 (95% CI 0.5 to 3.7)
What this article is about?
This is a multicenter study designed to derive a prediction rule to help identify which children were very low risk for IAI. Holmes et al. prospectively enrolled over 12,000 children with blunt torso trauma, who had an average age of 11 years. 761/12,044 had IAI (6.3%). Of these 761 a little more than a quarter needed one or more of the acute interventions listed below – 203/761 (26.7%);
- Laparotomy
- Angiographic embolization
- Transfusion for intraabdominal hemorrhage
- IV Fluids for ≥2 nights for pancreatic/bowel injuries
Using binary recursive partitioning (a multivariable statistical method used to create decision trees/rules) the authors identified the following factors, in descending order of importance, that were related to children being low risk for IAI requiring acute intervention:
- No evidence of abdominal wall trauma or seat belt sign
- Glasgow Coma Scale score ≥ 13
- No abdominal tenderness
- No evidence of thoracic wall trauma
- No complaints of abdominal pain
- No decreased breath sounds
- No vomiting
Here is the decision rule in graphical form:
Why is it important?
Obviously if you work in a Pediatric Emergency Department or a general ED you will see a child with a blunt belly injury. Understanding who is at risk for intraabdominal injury and who isn’t will save children from unnecessary CT scans. The decision rule seen above has the following statistical characteristics, which you should be aware of:
- Negative predictive value – 99.9% (95%CI 99.7% to 100%)
- Sensitivity – 97%( 95% CI 94% to 99%)
- Specificity – 42.5% (95% CI 41.6% to 43.4%)
- Negative likelihood ratio – 0.07 (95% CI 0.03 to 0.15)
How you can use it in your practice
Knowing why you should be worried about a child with blunt abdominal trauma is the key to making smart and prompt diagnostic and therapeutic decisions. So, here are some key take home points;
- Assessment for blunt IAI is a key part of the secondary survey (after the ABCs)
- Hemodynamically unstable children unresponsive to isotonic IV bolus and blood need a laparotomy.
- Patients with multiple risk factors as noted above who are hemodynamically stable should undergo abdominal/pelvic CT with contrast
- Note that FAST is less helpful diagnostically in children, as hemodynamically stable children with a positive FAST are much more likely need non-operative management as opposed to adults.
- Hemodynamically unstable children (hypotensive, need >40 mL/kg of isotonic fluid) with a positive FAST should undergo diagnostic laparotomy
- Children getting a CT should at least get a CBC and type and screen, ALT and AST.
- Every patient should have a chest X-Ray in the trauma bay to look for pneumothorax and widened mediastinum. If either/both are seen and the patient is stable a chest CT should be considered (after interventions like chest tubes of course).
- Hemodynamically stable with a reassuring exam, but concern for IAI (1 predictor from above like mild abdominal tenderness alone) should undergo lab testing and have serial abdominal exams. The labs include (along with likelihood of IAI if abnormal):
- Hematocrit ≤30% OR 2.6 (95% CI 0.9 to 7.5)
- Urinalysis >5 RBCs/hpf OR 4.8 (95% CI 2.7 to 8.4)
- Transaminases – AST ≥200 U/L or ALT ≥125 U/L OR 17.4 (95% CI 9.4 to 32.1)
- Amylase >125 IU/L and elevated Lipase Much less sensitive than the others, particularly amylase. Lipase in one study has a PPV of 75%
- Other factors associated with elevated odds of IAI should prompt imaging as well. These include:
- Low systolic blood pressure OR 4.1 (95% CI 1.1 to 15.2)
- Femur fracture OR 1.3 (95% CI 0.5 to 3.7)
