R. Uhlich1, J. Kerby1, P. Hu1, P. Bosarge1 1University Of Alabama at Birmingham,Acute Care Surgery,Birmingham, Alabama, USA
Introduction:
Pancreatic injury is a rare, although potentially devastating consequence of trauma. Diagnosis of and appropriate grading of these injuries remains challenging, with variable sensitivity reported for CT. Other methods, such as magnetic resonance cholangiopancreatography (MRCP) or endoscopic retrograde cholangiopancreatography (ERCP) may improve diagnostic accuracy, however are limited to specialized centers and take longer to perform. Serum amylase has been suggested for use as an adjunctive test to help identify patients with pancreatic injury, but remains controversial. We sought to evaluate its role in the diagnosis and management of pancreatic trauma.
Methods:
A retrospective case control study was performed at an American College of Surgeons verified level 1 trauma center from 2011-2017. All adult patients admitted to the trauma surgery service were eligible for inclusion, while patients with pregnancy or age <18 years old were excluded. Patients with pancreatic injury were identified from the trauma registry using ICD-10 codes. Corresponding controls with thoracic trauma, but without pancreatic or hollow viscus injury, were identified and matched using injury severity score (ISS), age, then gender in a 1:1 fashion. Pancreatic injuries were graded according to the AAST guidelines (Grades 1-5), with major injury identified as ≥ grade 3 (pancreatic ductal injury). Serum amylase levels were recorded from admission and throughout hospitalization. Hyperamylasemia was defined as a serum amylase >103 U/L, according to institutional standard. Analysis was performed using χ2 or Student's t-test for categorical and continuous variables respectively. The primary outcome of interest was admission serum amylase level. Secondary outcomes included serum amylase levels in isolated pancreatic injury and grade of pancreatic injury with elevated serum amylase.
Results:
51 patients with pancreatic injury and 51 corresponding controls were identified. Admission hyperamylasemia was identified in 18 patients with pancreatic injury and 2 controls (p<0.001). Average admission serum amylase levels were significantly increased in patients with pancreatic injury compared to without (122.24±136.37 vs 53.90±60.59, p=0.002), which persisted when controlling for hollow viscus injury (145.93±171.13 vs 48.93±32.35, p=0.006). Among patients with pancreatic injury, 36% (18/51) had hyperamylasemia on admission. Hyperamylasemia did not predict major pancreatic injury (50.0% vs 40.6%, p=0.57), need for operative intervention (100% vs 84.4%, p=0.15), or pancreatic resection (38.9% vs 37.5%, p=0.94) when compared to patients with normal admission amylase.
Conclusion:
Pancreatic injury results in higher mean levels of admission serum amylase. However, measurement of serum amylase is of questionable clinical value as hyperamylasemia fails to differentiate major and minor pancreatic trauma or need for operative intervention.