The presence of abnormal cells, other morphological characteristics, or cellular inclusions may signify a potentially life-threatening or serious health condition and should be investigated. Examples are the presence of sickle cells, moderate numbers of spherocytes, marked schistocytosis, oval macrocytes, basophilic stippling, nucleated RBCs (if the patient is not an infant), or malarial organisms.

Note and immediately report to the health-care provider (HCP) any critically increased or decreased values and related symptoms. Timely notification of critical values for lab or diagnostic studies is a role expectation of the professional nurse. Notification processes will vary among facilities. Upon receipt of the critical value, the information should be read back to the caller to verify accuracy. Most policies require immediate notification of the primary HCP, hospitalist, or on-call HCP. Reported information includes the patient’s name, unique identifiers, critical value, name of the person giving the report, and name of the person receiving the report. Documentation of notification should be made in the medical record with the name of the HCP notified, time and date of notification, and any orders received. Any delay in a timely report of a critical value may require completion of a notification form with review by Risk Management.

Low RBC count leads to anemia. Anemia can be caused by blood loss, decreased blood cell production, increased blood cell destruction, or hemodilution. Causes of blood loss include menstrual excess or frequency, gastrointestinal bleeding, inflammatory bowel disease, or hematuria. Decreased blood cell production can be caused by folic acid deficiency, vitamin B₁₂ deficiency, iron deficiency, or chronic disease. Increased blood cell destruction can be caused by a hemolytic reaction, chemical reaction, medication reaction, or sickle cell disease. Hemodilution can be caused by congestive heart failure, renal failure, polydipsia, or overhydration. Symptoms of anemia (due to these causes) include anxiety, dyspnea, edema, hypertension, hypotension, hypoxia, jugular venous distention, fatigue, pallor, rales, restlessness, and weakness. Treatment of anemia depends on the cause.

High RBC count leads to polycythemia. Polycythemia can be caused by dehydration, decreased oxygen levels in the body, and an overproduction of RBCs by the bone marrow. Dehydration by diuretic use, vomiting, diarrhea, excessive sweating, severe burns, or decreased fluid intake decreases the plasma component of whole blood, thereby increasing the ratio of RBCs to plasma, and leads to a higher than normal Hct. Causes of decreased oxygen include smoking, exposure to carbon monoxide, high altitude, and chronic lung disease, which leads to a mild hemoconcentration of blood in the body to carry more oxygen to the body’s tissues. An overproduction of RBCs by the bone marrow leads to polycythemia vera, which is a rare chronic myeloproliferative disorder that leads to a severe hemoconcentration of blood. Severe hemoconcentration can lead to thrombosis (spontaneous blood clotting). Symptoms of hemoconcentration include decreased pulse pressure and volume, loss of skin turgor, dry mucous membranes, headaches, hepatomegaly, low central venous pressure, orthostatic hypotension, pruritus (especially after a hot bath), splenomegaly, tachycardia, thirst, tinnitus, vertigo, and weakness. Treatment of polycythemia depends on the cause. Possible interventions for hemoconcentration due to dehydration include intravenous fluids and discontinuance of diuretics if they are believed to be contributing to critically elevated Hct. Polycythemia due to decreased oxygen states can be treated by removal of the offending substance, such as smoke or carbon monoxide. Treatment includes oxygen therapy in cases of smoke inhalation, carbon monoxide poisoning, and desaturating chronic lung disease. Symptoms of polycythemic overload crisis include signs of thrombosis, pain and redness in extremities, facial flushing, and irritability. Possible interventions for hemoconcentration due to polycythemia include therapeutic phlebotomy and intravenous fluids.