RT Book, Section A1 Kasper, Dennis L. A1 Fauci, Anthony S. A1 Hauser, Stephen L. A1 Longo, Dan L. A1 Jameson, J. Larry A1 Loscalzo, Joseph SR Print(0) ID 1128782364 T1 Cyanosis T2 Harrison's Manual of Medicine, 19e YR 2016 FD 2016 PB McGraw-Hill Education PP New York, NY SN 9780071828529 LK accessmedicine.mhmedical.com/content.aspx?aid=1128782364 RD 2024/03/28 AB Bluish discoloration of the skin and/or mucous membranes are usually due to elevated quantity of reduced hemoglobin (>40 g/L [>4 g/dL]) in the capillary blood vessels. Findings are most apparent in the lips, nail beds, ears, and malar eminences.