Blunt Liver Injury

ATOMIC (A Trauma Outcomes and Management Investigation Consortium) began around 2010 as a multi-center prospective study to develop evidence-based algorithms for solid organ injury management, starting with 5 hospitals and expanding to 10.

Early research by Sam Smith and colleagues in Arkansas demonstrated that patients with solid organ injury could be managed based on hemodynamic status rather than CT grade of injury, published in papers including 'Throwing Out the Grade Book.'

Hypotension is a late finding in pediatric hemorrhagic shock; almost half of patients requiring early transfusion are not hypotensive.

The terminology 'stable' and 'unstable' was abandoned in favor of 'bleeding or having bled recently' because defining hemodynamic stability in children is problematic: concurrent head injuries may prevent tachycardia, some unstable patients are not hypotensive, and tachycardia may be due to pain rather than bleeding.

When a hypovolemic pediatric patient arrives, you only know they have bled; you often don't know if they're still bleeding until you give them blood and they prove ongoing bleeding. Children have superior ability to stop bleeding compared to adults.

Shock Index Pediatric Adjusted (SIPAA) cutoffs: ages 4-6 greater than 1.2, ages 7-12 greater than 1.0, ages 13+ greater than 0.9. An elevated shock index misses very few patients in hypovolemic shock; if shock index is not elevated, the patient is probably not actively bleeding.

After 20 mL/kg of crystalloid, blood transfusion should be initiated if non-operative management is desired and good outcomes are the goal. This contrasts with older ATLS guidelines recommending 60 mL/kg crystalloid before blood.

Adult literature shows that excessive crystalloid dilutes the benefit of 1:1:1 resuscitation (Duchesney, New Orleans) and decreases success of non-operative management (John Holcomb). Children are somewhat more resistant to negative effects of crystalloid than adults, but excess crystalloid still causes adverse effects including prolonged ventilation.

One massive transfusion trial found that giving blood early and often prevented patients from progressing to require massive transfusion, suggesting early blood prevents DIC.

TEG (thromboelastography) and ROTEM (rotational thromboelastometry) directed component therapy makes theoretical sense and is used at Phoenix Children's Hospital, but definitive evidence comparing directed therapy to 1:1:1 ratios in children requires a randomized controlled trial.

Angioembolization is safe in pediatric blunt liver and spleen injury. For splenic injury, no patients who underwent embolization went on to fail non-operative management.

Many patients with hepatic injury who underwent angioembolization still required laparoscopy or washout, often converted from active bleeding to managing bile complications or intra-abdominal blood.

Many patients with contrast extravasation on CT will stop bleeding spontaneously without angioembolization. Angioembolization criteria should be similar to failure of non-operative management: persistent bleeding requiring ongoing blood transfusion.

For ICU admission: grade 1-4 injuries can be managed on the floor if hemodynamically stable or not actively bleeding. Grade 5 injuries should go to the ICU based on injury grade alone, though this represents a small subset of patients.

The threshold for failure of non-operative management is 40 mL/kg of all blood products, based on data from NEF and military experience showing patients transfused more than 40 mL/kg are more likely to need operation and more likely to die.

Bed rest was never included in the original APSA protocols (per Steve Stiglianos) but became part of the culture. There is no literature supporting bed rest for solid organ injury.

One adult study comparing bed rest versus no bed rest found no increased incidence of bleeding without bed rest. For renal injury, bed rest makes no difference whether patients walk to the bathroom or remain on strict bed rest.

Patients with blunt liver or spleen injury showing no signs of bleeding, no hemodynamic instability, and no hematocrit drop do not need a minimum hospitalization time. An 18-hour observation period is sufficient; if they haven't bled in 18 hours, they are very unlikely to bleed. This is supported by data showing all transfused patients and all failures occurred early.

Serial hemoglobins are not necessary in stable patients. Hemoglobin drops for multiple reasons unrelated to bleeding: lab error, drawing upstream from IV, dilution from excess fluid. Physical examination and vital signs (especially rising heart rate, poor capillary refill, pallor, cold extremities) are better indicators of ongoing bleeding and will identify every patient needing transfusion or failing non-operative management.

Half of patients who fail non-operative management do so because they develop peritonitis, not because of continued bleeding.

Many patients with low-grade injuries never showed for follow-up clinic appointments. Telephone follow-up was implemented for low-grade injuries to confirm patient status without requiring additional missed school days.

Follow-up visits for higher-grade injuries have not provided much benefit to patients. Patients with complications presented to the emergency room with symptoms; the follow-up visit itself did not identify problems or change management.

Discharge instructions should list symptoms that indicate complications: abdominal pain, respiratory problems (for splenic injury), and jaundice. All direct patients back to the emergency room except jaundice, which warrants a phone call to the office for triage since it may represent hematoma mobilization rather than bile leak.

Most patients with spleen injuries do not need follow-up imaging. Patients with liver injuries might benefit from follow-up ultrasound, but this remains uncertain.

Studies performing routine ultrasounds found many pseudoaneurysms, but the number was discordant with patients who developed delayed bleeding or complications. Having an asymptomatic pseudoaneurysm does not mean the patient will have delayed bleed or complication; the risk is less than 10% and likely much lower.

It is extremely rare for any patient who goes home from the hospital doing well to develop a finding that would put them at risk for life-threatening bleed.

Children with solid organ injury can return to school but need to change classes 5 minutes before other students to avoid hallway contact. They cannot participate in gym class or physical education.

Activity restriction duration follows the APSA recommendation of grade plus 2 weeks (e.g., grade 4 injury = 6 weeks restriction). This is based on expert opinion, not scientific evidence.

Early recurrent hypotension (patient responds to transfusion, becomes stable, then becomes unstable again before reaching ICU) represents failure of non-operative management. This is different from hemoglobin drifting down in the ICU. The patient needs to go to the operating room or angio suite very quickly.

The APSA Outcomes Committee and Trauma Committee conducted a retrospective review to update guidelines on liver and spleen blunt trauma.