Tufts OpenCourseware
Search
Author: Kanchan Ganda, M.D.
Color Key
Important key words or phrases.
Important concepts or main ideas.

1. Overview

Anemia is associated with a reduction in the hemoglobin content of the blood or a reduction in the number of circulating RBCs. This decreases the oxygen carrying capacity of the blood, resulting in tissue hypoxia. It frequently results in a decreased exercise tolerance.

Anemias may be:

  • Hemolytic, as in abnormal hemoglobin synthesis, e.g., sickle-cell anemia (HBSS), or thalassemia (Cooley’s anemia).
    • Appears early in life
    • Frequent episodes of hemolytic crisis, associated with bone pains, fever, worsening of anemia and tenderness in the splenic area.
  • Nutritional
    • Iron deficiency
    • B12 deficiency
    • Folate deficiency
      • The most common type of anemia is iron deficiency anemia and the leading cause of iron deficiency anemia is chronic blood loss. Common sites of chronic blood loss are the gastrointestinal tract; menstrual bleeding; and chronic intake of aspirin, NSAIDs and corticosteroids leading to gastritis or peptic ulceration.
  • Aplastic Anemia
    • Caused by depression of the bone marrow.
    • Often associated with lowered WBC and platelet counts.
    • The normal hemoglobin levels for females is 12–14 g/dL. For males it is 14–18 g/dL.

2. Basic Discussion of Anemia

2.1. Mild Anemia

Mild anemia occurs when associated with a drop of Hb by 25% of normal. Symptoms include tiredness, weakness, fatigue, anorexia (loss of appetite), and decreased stamina (ability to perform normal range of activities). All the symptoms are experienced upon exertion.

2.2. Moderate Anemia

Moderate anemia occurs when associated with a drop of Hb by 25- 50% of normal. The patient develops the above-mentioned symptoms at rest as well as upon exertion.

2.3. Severe Anemia

Severe anemia occurs when the Hb content of the blood falls to below 50% normal values. In addition to the moderate anemic symptoms, the patient frequently complains of orthopnea (shortness of breath on lying flat in bed), cough with expectoration (the patient could expectorate a blood tinged sputum occasionally, but is usually a white frothy or foamy sputum), and severe palpitations (tachycardia). If severe anemia is associated with congestive heart failure (CHF), you will observe distended neck veins and ankle edema (swelling of the ankles due to a collection of fluid). We confirm ankle edema by pressing our thumb into the tissue at the ankle and if, upon removal, it remains indented, the patient has ankle edema. Severe anemia leads to CHF. CHF is thus associated with symptoms like orthopnea, palpitations, cough with expectoration of a white frothy or foamy sputum, and signs such as distended neck veins, bilateral basilar rales on auscultation of the lungs and ankle edema.

Note: As the heart fails as a pumping organ, fluid collects in the lungs causing the cough with expectoration. This presence of fluid in the lungs causes SOB (shortness of breath) as well. The fluid in the lungs also causes blood to back up into the right ventricle to the right atrium and then to the neck veins causing them to become distended. Presence of fluid at the base of the lungs can be heard by auscultation in physical examination. With CHF, we hear Bilateral Basal Rales, a crackling sound heard at the base of the lungs upon auscultation of the lungs with a stethoscope.

Signs to look for with mild to moderate anemia are pallor of the conjunctiva, oral mucosa and nail beds. In severe anemia, additionally you will see white palmar creases.

2.4. CHF (Congestive Heart Failure)Associated with Severe Anemia

CHF (Congestive Heart Failure) is associated with severe anemia: As the anemia progresses, all of the symptoms worsen. The tissues need more oxygen and the tissue hypoxia becomes worse. The patient experiences palpitations (tachycardia), as an attempt to get more oxygen to the hypoxic tissues. You will note a hyperdynamic circulation on physical examination, as a result of the severe anemia. The blood gushes very rapidly through the vessels and heart valves resulting in a functional systolic heart murmur which is heard only in the pulmonic valve area. There is no valvular defect, so you don’t premedicate these patients. The murmur is caused by severe underlying anemia. Once the anemia is treated, this murmur will disappear.

3. Hemolytic/Congenital Anemia

The patient is born with this condition and is symptomatic from childhood. This type of anemia is prevalent in blacks, middle-eastern and Mediterranean populations. You should ask the patient if he/she or his/her family has ever been diagnosed with anemia in the past.

  • Examples include HbSS, Thalassemia, and G6PD (Glucose-6-phosphate dehydrogenase) deficiency anemia.

Note:NEVER give aspirin or NSAIDS to these patients because these drugs can worsen hemolytic anemia. These drugs affect platelet function and will cause hemolysis. We don’t use anesthetics containing epinephrine particularly in G6PD anemia patients because they contain bisulfites which are the oxidant preservatives to the epinephrine in the L.A.. Trimethoprim-Sulphamethoxazole an antibiotic, should also be avoided in G6PD patients. Oxidant drugs like sulpha and acetaminophen precipitate hemolysis in these patients. We only use carbocaine with these patients.

Note: Patients with a history of hemolytic anemia will tell you that they have had numerous hospital admissions with symptoms of (1) high fever, (2) pain in the long bones (due to thrombosis), and (3) pain in the left upper quadrant (LUQ). The pain in the LUQ is due to the enlarged spleen destroying RBC’s at a high rate. This is a hemolytic crisis. The spleen is usually removed when the patient is in his/her early 20’s with this form of anemia, to limit the hemolytic episodes.

4. Iron Deficiency Anemia

Iron deficiency is the most common cause of anemia. Chronic blood loss is the most frequent precipitating factor. Always ask the patient about long-standing intake of drugs like aspirin, NSAIDs, and corticosteroids. These drugs can cause gastric mucosal irritation or peptic ulceration, resulting in chronic blood loss.

Upper gastrointestinal (GI) bleeding (esophagus, stomach, and small intestine) causes black, tarry stools, so always question the patient about the color of his/her stools.

Chronic lower GI bleeding (colon, rectum) can also lead to iron deficiency anemia. In this case, the patient will complain of fresh blood in the stools.

Note:The Guiac test is used to determine the presence of blood in the stools.

Menstrual blood loss is another important source of chronic bleeding. Occurrence of menorrhagia (heavy menstrual cycles) and metrorrhagia (frequent menstrual cycles) should always be established in female patients suffering from anemia. Always let the patient know why you need to ask these questions , as they could be embarrassing for the patient.

Iron deficiency anemia affects all age groups. In children, chronic blood loss is frequently due to intestinal parasites.

Iron deficiency causes patients to have abnormal cravings—referred to as pica. Patients crave large quantities of ice, dirt, chalk, or plaster!

Iron deficiency anemia is treated with iron pills containing ferrous sulfate salts. These pills may cause abdominal cramping and dark green coloring of the stools which could be confused with black, tarry stools.

Do not prescribe erythromycin or other Macrolides to patients taking these pills because this class of drugs frequently cause abdominal cramping.

4.1. Oral Cavity Manifestations

Recurrent aphthous ulcerations and angular cheilitis are common oral manifestations with iron deficiency anemia. Angular cheilitis is cracking at the corners of the mouth. Candidiasis can super infect the angular cheilitis. An anti-fungal cream is usually prescribed to combat the super infection. Laboratory finding: hypochromic, microcytic cells on CBC.

5. B12 Deficiency Anemia

B12 deficiency anemia is frequently seen in older women, around the ages of 55-60. Common initial complaint is a burning tongue. Often at this time the patient may be labeled as being psychosomatic, because no other symptoms or signs may be present.

As the condition progresses, there will be depapilation, microglossia (small tongue), beefy red tongue, angular cheilitis, circumoral and peripheral tingling numbness, difficulty swallowing (dysphagia), painful swallowing (odynophagia).

When the B12 deficiency is due to pernicious anemia the patient will also have HCl (hydrochloric acid) and intrinsic factor secretion levels in the stomach.

Diagnosis is confirmed by checking the serum B12 levels, doing the Schilling’s test and demonstrate a CBC showing an increased MCV and MCH. The Schilling test is performed to evaluate Vitamin B12 absorption.

Intrinsic factor is produced in the stomach and is required for Vitamin B12 absorption. If the intrinsic factor is not made, the body cannot absorb Vitamin B12. Low levels of Vitamin B12 therefore can occur from the lack of intrinsic factor and this can be due to:

  • Pernicious anemia gastrectomy (partial removal of stomach)
  • Inadequate absorption due to bowel disease
  • Bacterial overgrowth in the intestine
  • Pancreatic insufficiency or certain medications.

The Schilling test is most commonly used to evaluate patients for pernicious anemia. Vitamin B12 deficiency is treated by injecting B12 in the gluteal muscles once or twice a month.

6. Folate Deficiency Anemia

Symptoms, signs and laboratory findings are similar to B12 deficiency anemia. This type of anemia can occur at any age. Commonly seen in alcoholics, patients receiving cancer medications or patients taking Phenytoin Sodium for Grand Mal seizures.

The deficiency is with folic acid and folate pills are given PO (by mouth) to alleviate this anemia.

7. Aplastic Anemia

This type of anemia occurs with depression of the bone marrow and subsequent underproduction of WBC’s, RBC’s, and platelets. This underproduction noted on the CBC is called pancytopenia. The MCV and MCH are normal, and this is referred to as a normocytic, normochromic anemia. Higher incidence of infection, tissue hypoxia, and bleeding often occur in this state of pancytopenia.

8. Dental Treatment of Anemic Patients

When treating anemic patients in the dental setting, avoid sedation with Diazepam as it depresses the respiratory center. Do not use aspirin or NSAIDs as they promote bleeding. If taken on a chronic basis, aspirin, NSAID’s, and corticosteroids can erode the gastric mucosal lining and cause chronic GI bleeding. Ask anemic patients whether they are taking these medications. We only prescribe Acetaminophen to anemic patients.

Note: Acetaminophen is contraindicated in G6PD patients as it is an oxidant.