In healthy individuals, hemoglobin levels above 7 grams per deciliter remain safe enough to forgo transfusion, providing there is a normal blood volume, according to Samir M Fakhry in an article in Critical Care. This also proves generally appropriate for critically ill patients and those with cardiovascular disease.
Previously, medical professionals believed a hemoglobin level of 10 grams per deciliter low enough to outweigh the dangers associated with blood transfusions, reports Sanjeev Sharma, MD et al writing in American Family Physician. However, recent studies have shown lower mortality rates when avoiding transfusion, given the individual maintains a hemoglobin level of 7 grams per deciliter. With the presence of varying cardiac or blood conditions, the danger of reaching this low a hemoglobin level increases.