Laboratory Tests for Trauma Patients

Core Laboratory Tests

Complete blood count (CBC) with hemoglobin/hematocrit measurements should be obtained, with repeated measurements to detect ongoing bleeding, as initial values may be normal despite significant blood loss 1
Platelet count should be maintained >100,000/mm³ in trauma patients with TBI or ongoing bleeding 2
Single hemoglobin/hematocrit measurements should not be used in isolation as they may mask early bleeding 1, 3
Serum lactate measurement is recommended as a sensitive marker of tissue hypoperfusion and shock severity 4, 5
Base deficit from arterial blood gas analysis provides an indirect estimation of global tissue acidosis due to impaired perfusion 5, 6
Serial lactate measurements provide valuable prognostic information; normalization within 24 hours is associated with improved survival 5
Early, repeated measurements of PT, APTT, fibrinogen, and platelet count should be performed to detect trauma-induced coagulopathy 4
Viscoelastic hemostatic assays (TEG/ROTEM) should be used when available to better characterize coagulopathy and guide hemostatic therapy 4

For suspected thoracoabdominal injuries, laboratory tests should include liver enzymes (AST, ALT), pancreatic enzymes (amylase, lipase), urinalysis, and renal function tests (BUN, creatinine) 7
Cardiac injury markers (troponin, CK-MB) should be considered in cases of chest trauma 7
In patients with TBI, coagulation studies are particularly important as coagulopathy is associated with progression of intracranial bleeding 2
Ionized calcium should be monitored and corrected in bleeding trauma patients 8
In cases where child abuse or metabolic bone disease is suspected, additional tests may include serum calcium, phosphorus, and alkaline phosphatase, parathyroid hormone and 25-hydroxy-vitamin D, and serum copper and ceruloplasmin 7

Initial laboratory tests should be obtained as soon as possible upon arrival 9, 1
Results should be available rapidly to guide resuscitation and treatment decisions 9
Serial measurements provide more valuable information than single measurements 1
Initial normal hemoglobin/hematocrit values may mask significant bleeding due to the time required for fluid shifts from interstitial space 1
Resuscitation fluids can dilute blood components and affect laboratory values, particularly hemoglobin/hematocrit 5