From the Guidelines
For suspected internal bleeding causing a sudden drop in hemoglobin, I recommend ordering a complete blood count (CBC) with differential, coagulation studies (PT/INR, PTT), and a comprehensive metabolic panel, as well as imaging studies such as an abdominal CT scan with contrast, which can identify bleeding sources in the abdomen, as suggested by the most recent guidelines 1.
Diagnostic Approach
The diagnostic approach should prioritize identifying the source and severity of the bleeding.
- A complete physical examination, including a digital rectal examination, should be performed to rule out other causes of lower gastrointestinal bleeding, as recommended by the WSES-AAST guidelines 1.
- Vital signs should be checked, and hemoglobin and hematocrit levels should be determined to evaluate the severity of the bleeding, as suggested by the WSES-AAST guidelines 1.
- Coagulation studies, including PT/INR and PTT, should be performed to assess coagulation, as recommended by the WSES-AAST guidelines 1.
- Blood typing and cross-matching should be considered in case of severe bleeding, as suggested by the WSES-AAST guidelines 1.
Imaging Studies
Imaging studies are essential in identifying the source of bleeding.
- An abdominal CT scan with contrast is usually appropriate as the next step for a hemodynamically stable patient with lower gastrointestinal bleeding, as recommended by the ACR Appropriateness Criteria 1.
- For hemodynamically unstable patients or those who have required >5 units of blood within 24 hours, CTA of the abdomen and pelvis without and with IV contrast or transcatheter arteriography/embolization may be considered, as suggested by the ACR Appropriateness Criteria 1.
Additional Tests
Additional tests may be necessary to assess tissue perfusion and oxygenation status.
- Lactate levels and arterial blood gases may be useful in evaluating tissue perfusion and oxygenation status, respectively.
- Focused assessment with sonography for trauma (FAST) can be valuable in trauma settings to detect free fluid.
- Type and cross-match for potential blood transfusion should be considered, especially in cases of severe bleeding.
Urgency of Tests
The urgency of these tests depends on the patient's hemodynamic stability.
- Unstable patients require immediate intervention alongside diagnostics, as suggested by the ACR Appropriateness Criteria 1.
- Stable patients may undergo a more thorough diagnostic workup before intervention.
From the Research
Diagnostic Orders for Possible Internal Bleeding
To diagnose possible internal bleeding related to a sudden drop in hemoglobin, the following diagnostic orders can be considered:
- Complete Blood Count (CBC) to assess the patient's blood cell components, including hemoglobin, hematocrit, and red blood cell indices 2, 3
- Basic Metabolic Panel to evaluate the patient's electrolyte and fluid status
- Coagulation panel to assess the patient's clotting ability
- Liver tests to evaluate liver function
- Type and crossmatch to prepare for potential blood transfusion 4
- Imaging studies, such as CT scans or ultrasound, to identify the source of bleeding
Laboratory Tests
Laboratory tests play a crucial role in diagnosing and managing internal bleeding. The following tests can be ordered:
- Hemoglobin and hematocrit to monitor the patient's blood loss and response to treatment
- Red blood cell indices, such as mean corpuscular volume (MCV) and red cell distribution width (RDW), to evaluate the patient's red blood cell characteristics 3
- White blood cell count and differential to assess the patient's inflammatory response
- Platelet count and mean platelet volume (MPV) to evaluate the patient's platelet function
Risk Stratification
Risk stratification is essential in managing patients with internal bleeding. The following factors can be considered: