hematoma

a bruise; bleeding into the body tissue around a blood vessel (if at the skin surface, it looks like a bruise)

hemolysis

breakdown in red blood cells

hepatoma

cancer or tumor of the liver

hypercalcemia

high blood calcium level

hyerkalemia

high blood potassium level

hypernatremia

high blood sodium level

hypocalcemia

low blood calcium level

hypokalemia

low blood potassium level

hyponatremia

low blood sodium level

hypoxia

low oxygen level in the blood