19: GI Bleeding

CHIEF COMPLAINT

CONSTRUCTING A DIFFERENTIAL DIAGNOSIS

The approach to GI bleeding is similar to the approach to other potentially life-threatening illnesses. Patient stabilization, specifically, hemodynamic stabilization is the first step in management. In a patient with GI bleeding, management precedes diagnosis, usually made by colonoscopy or esophagogastroduodenoscopy (EGD).

Initial management follows a regimented course. The patient must be hemodynamically stabilized, preparation must be made in case of further bleeding, and initial diagnostic tests must be completed.

1. Hemodynamic stabilization

   1. Clinically assess volume status.

      1. Signs of shock may be seen with 30–40% volume depletion.

      2. Orthostasis can be seen with 20–25% volume depletion.

      3. Tachycardia may be present with 15% volume depletion.

   2. Calculate necessary replacement (weight in kg × 0.6 (lean body weight made up of water) × % volume depletion).

   3. Replace fluid losses initially with normal saline or Ringer solution.

   4. Consider the need for blood transfusion.

      1. In patients who are not bleeding, withholding transfusions until the hemoglobin reaches 7–8 g/dL is a conservative approach supported by recent data.

      2. There has, until recently been general agreement on the following recommendations for transfusion in actively bleeding patients.

         • (1) Patients should receive a blood transfusion when there has been 30% loss of blood volume (manifested by tachycardia, hypotension, tachypnea, decreased urinary output, or CNS symptoms [eg, anxiety/confusion]).

         • (2) Alternatively, if 2 L of crystalloid have been given without successful resuscitation, blood should be transfused.

         • (3) If a hemoglobin level is available, actively bleeding patients should receive a transfusion when the level falls below 10 g/dL.

         • (4) If large amounts of blood are needed (> 4 units of packed red blood cells), fresh frozen plasma and platelets should also be given.

      3. A recent randomized trial of patients with upper GI bleeding compared a restrictive strategy of transfusion (threshold for transfusion of hemoglobin < 7 g/dL) with a liberal strategy (threshold of hemoglobin < 9 g/dL).

         • (1) This study demonstrated a mortality benefit with the restrictive strategy.

         • (2) Exclusion criteria in this study were massive exsanguinating bleeding, an acute coronary syndrome, symptomatic peripheral vasculopathy, stroke, or transient ischemic attack.

         • (3) All patients had endoscopy within 6 hours of presentation.

         • (4) Patients in this study also received blood if symptoms of anemia or massive bleeding developed or if they required surgery.

      4. It is important to remember that patients may initially have a normal hemoglobin level when they present with an acute hemorrhage. It will only fall after fluid resuscitation.

         Even after a large hemorrhage, patients may initially have a normal hemoglobin level. The level will only fall after fluid resuscitation.

2. Preparation for further bleeding

   1. All patients should have their blood typed and be cross-matched for at least 2 units of ...