iron deficiency anemia, B12 deficiency anemia, sickle cell anemia

med surge II exam 3

What is the physiological role of iron in the human body, and what blood cell anomaly occurs in untreated Iron Deficiency Anemia (IDA)?

Iron is an essential mineral required for DNA synthesis, mitochondrial energy production, and hemoglobin formation for oxygen transport. Untreated IDA leads to tissue hypoxia and microcytic hypochromic anemia.

What hemoglobin threshold defines iron deficiency in adult males and non-pregnant females?

Hemoglobin less than 13 g/dL in males and less than 12 g/dL in non-pregnant females (or 2 standard deviations below the mean for age and sex).

What are the primary risk factors and leading causes of Iron Deficiency Anemia across different age groups?

Menstrual blood loss (menorrhagia in 10% of females of childbearing age), GI bleeding (ulcers, polyps, malignancies in adults > 50), poor nutrition (9% of toddlers 12–36 months), low socioeconomic status, pregnancy/lactation, and malabsorption (celiac disease, Crohn's, gastric bypass).

How are serum ferritin and total iron binding capacity (TIBC) used to diagnose Iron Deficiency Anemia?

Serum ferritin measures iron storage in the liver, spleen, and bone marrow; a low ferritin level indicates depleted iron stores. TIBC measures transferrin's ability to bind iron. In IDA, serum ferritin is low, TIBC increases (body makes more transferrin to capture iron), and transferrin saturation decreases.

What diagnostic procedures are indicated for postmenopausal females or males with unexplained Iron Deficiency Anemia?

A bidirectional endoscopy (upper GI view of esophagus/stomach for ulcers/inflammation) and a colonoscopy (lower GI view for polyps, hemorrhoids, inflammatory bowel disease, or colorectal malignancies) to identify occult GI bleeding.

What diagnostic test is performed for females presenting with heavy menstrual flow (menorrhagia) and IDA?

A pelvic and abdominal ultrasound to check for structural anomalies such as uterine fibroids.

What is the difference between dietary heme iron and nonheme iron, and which foods belong to each?

Heme iron comes from animal products and is absorbed more readily (red meat, turkey, chicken, salmon). Nonheme iron comes from plant foods (dark leafy greens like spinach/collard greens, beans, lentils, tofu, raisins, fortified cereals).

What dietary component enhances the absorption of nonheme iron, and what foods contain it?

Vitamin C (found in citrus fruits, berries, and tomatoes) significantly aids in the intestinal absorption of nonheme iron when consumed together.

How should oral ferrous sulfate supplements be administered for optimal absorption?

Take on an empty stomach because the low gastric pH facilitates iron absorption.

What common, harmless side effect of oral iron supplements must be distinguished from a gastrointestinal bleed?

Stools turning dark green or black. However, black, tarry stools (melena) require evaluation to rule out active GI bleeding.

What GI side effect frequently occurs with oral iron, and how should the client manage it without stopping therapy?

Constipation and nausea. The client should increase daily fluid intake (drink at least 8 glasses of water daily) but should not stop taking the supplement.

How does timing interact between oral iron supplements and antacids?

Antacids interfere with iron absorption. Iron supplements should be taken 2 hours before or 4 hours after an antacid.

How long does it take to see an initial response to oral iron, and how long should therapy continue?

Initial hemoglobin response typically occurs within 14 days, but oral iron supplementation must generally continue for at least 3 months to rebuild iron stores.

When is intravenous (IV) iron indicated over oral iron supplements?

When there are severe GI absorption issues (such as inflammatory bowel disease/IBS) or during pregnancy to achieve higher hemoglobin and ferritin levels more rapidly.

What safety precautions should the nurse enforce for a client experiencing severe fatigue from Iron Deficiency Anemia?

Assess for dizziness, encourage scheduled rest periods, assist with ambulation, provide assistive devices (cane/walker), and instruct the client to limit physical activity until anemia improves to prevent undue falls or injuries.

What is the physiological role of Vitamin B12 (cobalamin), and where is it absorbed and stored in the body?

Vitamin B12 synthesizes DNA, myelin, and fatty acids. It requires intrinsic factor for absorption in the terminal ileum; excess B12 is stored in the liver.

What is pernicious anemia, and what is its pathophysiology?

An autoimmune condition characterized by the autoimmune destruction of gastric parietal cells, resulting in a lack of intrinsic factor and preventing Vitamin B12 absorption in the terminal ileum. It is most prevalent in individuals of Northern European ancestry.

Why are clients who underwent bariatric surgery (e.g., Roux-en-Y gastric bypass) at high risk for Vitamin B12 deficiency?

The surgical procedure either bypasses or removes the sections of the stomach that produce intrinsic factor or interferes with B12 absorption in the ileum.

Why are strict vegans or vegetarians at risk for Vitamin B12 deficiency?

Vitamin B12 is naturally found primarily in animal-derived foods (red meat, poultry, fish, eggs, dairy); vegans require fortified foods or supplements.

Which common long-term medications increase the risk of Vitamin B12 deficiency by impairing absorption?

Proton pump inhibitors (PPIs), metformin, H2 blockers, antiseizure medications, and oral contraceptives.

Why are adults over 75 years of age at increased risk for Vitamin B12 deficiency?

Due to gastric atrophy, decreased intrinsic factor production, slowed metabolism, and chronic use of medications that impair absorption (metformin, PPIs).

What classic gastrointestinal clinical sign is specific to Vitamin B12 deficiency?

Glossitis (a smooth, beefy red tongue).

What specific neurological red flags distinguish Vitamin B12 deficiency from Iron Deficiency Anemia?

Peripheral neuropathy (numbness, tingling, or burning pain in extremities), ataxia / gait disturbances / balance issues, visual deficits, confusion, memory loss / forgetfulness, and subacute combined degeneration of the spinal cord due to myelin damage.

Why can untreated Vitamin B12 deficiency lead to permanent, irreversible physical disability?

Vitamin B12 is required for myelin synthesis; B12 deficiency causes damaged myelin, leading to subacute combined degeneration of the spinal cord and neurological deficits that become irreversible if left untreated.

What laboratory test results confirm a diagnosis of Vitamin B12 deficiency anemia?

CBC showing macrocytic/megaloblastic RBCs (elevated MCV), serum B12 level below 160 pg/mL (expected reference range 160–950 pg/mL), elevated methylmalonic acid (MMA), and elevated homocysteine levels.

What infection is associated with impaired B12 absorption and gastric ulcers?

Helicobacter pylori (H. pylori) bacterial infection, which causes gastritis and impairs B12 absorption.

What is the primary safety priority for a client presenting with Vitamin B12 deficiency neuropathy and ataxia?

Fall precautions and injury prevention due to gait instability, impaired peripheral sensation, and visual deficits.

What administration routes are available for Vitamin B12 replacement therapy?

Intramuscular (IM) cyanocobalamin injections (daily initially, then monthly for life if pernicious anemia/gastrectomy), nasal sprays, sublingual gels, or high-dose oral supplements.

What dietary sources should the nurse recommend to a non-vegan client with B12 deficiency?

Lean red meat, poultry, fish, eggs, milk/dairy products, and B12-fortified cereals or plant milks.

How does elevated homocysteine from B12/folate deficiency impact systemic health?

Elevated homocysteine levels are independently linked to an increased risk of cardiovascular disease.

What is the genetic transmission pattern of Sickle Cell Anemia, and what is the difference between disease and trait?

It is an autosomal recessive disorder. Both biological parents must carry the trait for a child to inherit the disease (25% chance per pregnancy). Single-trait carriers produce both normal and sickle hemoglobin and are asymptomatic.

What is the pathophysiology of red blood cell sickling in Sickle Cell Anemia?

A single gene mutation causes hemoglobin to become sticky and rigid, forming RBCs into a crescent or "C" shape. Sickle cells move slowly, clump together, and block blood flow, causing widespread tissue hypoxia and organ damage.

How long do sickle red blood cells survive in circulation compared to normal red blood cells?

Sickle RBCs die rapidly in 10 to 20 days, compared to normal RBCs which live approximately 120 days, causing chronic hemolytic anemia and jaundice.

At what age do infants typically begin showing clinical manifestations of Sickle Cell Anemia, and why?

Around 6 months of age, as fetal hemoglobin (HbF) transitions to abnormal adult sickle hemoglobin (HbS).

What environmental and physiological triggers can precipitate a vaso-occlusive crisis (VOC) or sickling event?

Dehydration, hypoxia, cold or hot temperature extremes, high altitudes (unpressurized flying or mountain travel), infection/fever, physical overexertion, stress, and tobacco smoke exposure.

What is a vaso-occlusive crisis (VOC), and where does pain typically occur?

An acute episode where rigid sickle cells obstruct microvascular blood flow, causing severe, agonizing tissue ischemia and pain in the joints, chest, abdomen, and extremities.

What is Acute Chest Syndrome, why is it life-threatening, and what are its manifestations?

A critical complication where sickled cells block blood flow to the lungs. Manifestations include fever, severe chest pain, dyspnea, hypoxia, cough, and pulmonary infiltrates.

Why are clients with Sickle Cell Anemia at extreme risk for severe bacterial infections and sepsis?

Repeated sickling episodes damage the spleen, resulting in functional asplenia (loss of splenic immune function).

What essential prophylactic measures protect sickle cell clients against life-threatening infections?

Routine immunizations (annual flu vaccine, pneumococcal vaccines), strict hand hygiene, and safe food preparation practices.

What early pediatric sign of vaso-occlusive crisis occurs in infants with sickle cell disease?

Dactylitis (painful swelling of the hands and feet due to microvascular occlusion).

What is the mechanism of action and therapeutic benefit of Hydroxyurea in sickle cell disease?

Hydroxyurea is an oral ribonucleotide reductase inhibitor that reactivates fetal hemoglobin (HbF) production, significantly reducing pain crises and acute chest syndrome.

What safety parameters and client teaching are required for a client prescribed Hydroxyurea?

Monitor CBC every 4 weeks (risk of myelosuppression/bone marrow suppression); do NOT crush capsules; warn about skin hyperpigmentation and nail discoloration; note that it takes 3 to 6 months for improvement; contraindicated in pregnancy (teratogenic).

What is iron overload (hemosiderosis) in sickle cell management, and how is it treated?

A condition resulting from frequent blood transfusions where excess iron accumulates in the heart, liver, and organs. It requires iron chelation therapy to prevent fatal organ damage.

What medical therapy offers a permanent cure for Sickle Cell Anemia?

Allogeneic hematopoietic stem cell transplant (HSCT), though limited by finding a compatible donor match.

What screening exam must sickle cell clients undergo annually to prevent vision loss?

An annual exam with an ophthalmologist or optometrist to screen for sickle retinopathy and vessel occlusions in the eyes.

NCLEX Emergency Pain Protocol: What route and pain management steps are prioritized during an acute vaso-occlusive pain crisis in the ED?

Promptly administer prescribed IV opioids (morphine, hydromorphone). If IV access cannot be obtained immediately, administer via the subcutaneous route. Reassess pain every 15 to 30 minutes.

NCLEX Fluid & Oxygen Protocol: What hydration and oxygenation targets are set for a client in a sickle cell crisis?

Administer IV fluids and encourage oral fluids (at least 8 glasses of water daily) to decrease blood viscosity. Administer supplemental oxygen to maintain SpO2 >= 95% on room air.

NCLEX Diagnostic Distinction: How does the nurse differentiate Vitamin B12 deficiency from Iron Deficiency Anemia during physical assessment?

Both present with fatigue, dyspnea, and pallor. B12 deficiency uniquely presents with neurological deficits (bilateral paresthesias, peripheral neuropathy, gait ataxia, confusion) and glossitis (beefy red tongue).

NCLEX Lab Diagnostic: What does an elevated reticulocyte count indicate in an anemic client?

It measures the rate of new red blood cell production by the bone marrow in response to anemia or RBC destruction.

NCLEX Evaluation Timing: When must the nurse reassess a client's pain level following opioid or non-opioid intervention for a vaso-occlusive crisis?

Within 15 to 30 minutes post-medication administration.