orthostasis, chest pain or dyspnea, decreased urine output, and any change in mental status FIGURE 93.1 Causes of blood loss Assessment of hemodynamic parameters to identify signs of impending cardiopulmonary collapse (e.g., severe tachycardia, hypotension, hypoxia) is critical, remembering that hypotension is a late finding in shock in young children Physical examination should assess for location of blood loss and signs of systemic illness that may cause anemia Signs of end-organ dysfunction, such as change in mental status, congestive heart failure, or renal insufficiency should be noted In the trauma patient, bleeding may be evident or occult, as in the case of femoral, pelvic, or abdominal (including both intra- and retroperitoneal) hemorrhage These may be hemodynamically significant but not immediately obvious The presence of trauma itself may be subtle in nonaccidental injury Consider gastrointestinal or gynecologic bleeding when the etiology is unclear Diagnostic Testing Laboratory testing for patients with suspected blood loss includes complete blood count (CBC), reticulocyte count, coagulation studies, and a type and screen, or type and crossmatch if transfusion is anticipated If the etiology of the anemia is unclear, obtain stool guaiac for occult blood, hemolysis labs, and other studies as outlined below (see section on Hemolytic Anemia) Send a pregnancy test if clinically indicated Management