Sublingual Microcirculatory Characteristics of a Case of Profound Chemotherapy-Induced Anemia Treated With a Hemoglobin-Based Oxygen Carrier

Handheld vital microscopy (HVM) can deepen our understanding of hematologic diseases and therapeutics. However, limited reports have assessed human microcirculation during profound anemia, and response to hemoglobin-based oxygen carriers (HBOCs). A 58-year-old woman presented with constitutional symptoms and was diagnosed with acute myeloblastic leukemia. Subsequently, the patient clinically decompensated and was found to have a hemoglobin of 1.9 g/dL. Human blood product administration was not consistent with her beliefs, and she received supportive care with HBOC-201. Concomitantly, her sublingual microcirculation revealed a markedly low microvascular flow index (2.59±0.26), proportion perfused vessels (66.8±18.8%), perfused vessel density (4.41±0.56 mm/mm 2 ), and total vessel density (6.93±1.91 mm/mm 2 ). HVM imaging is a promising point-of-care device for various hematologic conditions, with the potential to understand tissue-level perfusion in novel clinical scenarios, including profound anemia and HBOC administration, as illustrated in this case report.