<prompt> Patients with underlying serious hea disease need to have their hemoglobin level kept above:8 gdl9 gdl10 gdl11 gdl  <response>: Patients without serious underlying cardiovascular or pulmonary disease can tolerate hemoglobin levels above 8 gdL; Patients with serious underlying cardiovascular or pulmonary disease need to have their hemoglobin levels kept above 11 gdL. Reference: Harrisons Principles of Internal Medicine, 18th Edition, Page 851 