Hematologic/immunologic disorders

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CHAPTER 10 Hematologic/immunologic disorders

General Hematology Assessment,

Anaphylactic Shock,

Profound Anemia and Hemolytic Crisis,

Bleeding and Thrombotic Disorders,

General hematology assessment

Parameters	Significance	Normal Values
Hemoglobin (Hgb)	Protein in red blood cells containing iron which carries oxygen to tissues	14–18 g/dL (males) 12–16 g/dL (female)
Hematocrit (Hct)	The percentage of red blood cells in the bloodstream. When the Hct is too low, those with anemia may experience fatigue.	42%–52% (male) 37%–47% (female)
White blood cells (WBCs)	Cells of the immune system that protect the body from bacterial, fungal, and viral infections. Incidence of infection increases when WBCs are decreased.	5000–10,000/mm³
Absolute neutrophil count (ANC)	The number of neutrophils (mature white cells) in the blood. Neutrophils are a type of WBC that help fight infection. When ANC decreases, the patient is neutropenic and more prone to infection. Risk of infection increases when the ANC falls below 2000 and the greatest risk is below 500—a “right shift” on the WBC differential.	2000/mm³ and above
WBC differential	Measures the percentage of each type of WBC in the total WBC count—a “left shift.” Indicates a large percentage of WBCs are neutrophils; indicates the bone marrow has been stimulated by a severe infection to produce neutrophils to fight the infection. Bands are immature neutrophils. “Right shift”: Indicates a small percentage of WBCs are neutrophils, putting the patient at higher risk for an infection; neutropenia. Eosinophilia: Increased eosinophils indicate an allergic reaction is present. Monocytes and lymphocytes: Act as “backup” to the neutrophils. Percentages increase during infection when oncology patients begin bone marrow recovery. If levels do not rise and then fall in a normal pattern, this can be a indication the patient has a poor prognosis for recovery.	Neutrophils: 50%–62% Bands: 3%–6% Monocytes: 3%–7% Basophils: 0%–1% Eosinophils: 0%–3% Lymphocytes: 25%–40%
Platelets (thrombocytes)	Cells that form the matrix on which blood clots are formed	150,000–400,000/mm³

Information specific to hematologic and/or immunologic findings for each section is presented in disease-specific sections. The basic assessment can be a part of every patient’s assessment to determine the risk of development or presence of a hematologic or immunologic disorder.

Anaphylactic shock

Pathophysiology

Anaphylaxis (anaphylactic shock) is a potentially life-threatening condition resulting from an exaggerated or hypersensitive response to an antigen or allergen. The classic presentation occurs in a sensitized person (i.e., someone who has been exposed previously to the same antigen), within 1 to 20 minutes of exposure to the antigenic substance, most often drugs, foods, insect stings or bites, antisera, and blood products. The hypersensitive response results in airway inflammation that causes obstruction and respiratory distress, which can lead to respiratory arrest, with a relative hypovolemia caused by massive vasodilation. Fluids shift from the vasculature into interstitial spaces, creating a false hypovolemia or vasogenic (vasodilated) shock, which progresses to end-organ dysfunction secondary to tissue hypoxia from poor perfusion.

The hypersensitivity response occurs primarily on the surface of the mast cells of the lungs, small blood vessels, and connective tissue. The antigen combines with sensitized antibodies from previous exposure (usually immunoglobulin E [IgE] type) and attaches to basophils circulating in the blood. Inflammatory mediators are then released from the granules within the cells, including histamine, serotonin, kinins, and eosinophil and neutrophil chemotactic factors. Histamine is the primary mediator of an anaphylactic response. Activation of histamine receptors causes increased capillary permeability, increased pulmonary secretions, bronchoconstriction, and systemic vasodilation.

The antigen-antibody complexes activate production of prostaglandins and leukotrienes, which are termed slow-reacting substances of anaphylaxis (SRSA)—chemical mediators that produce systemic effects with potentially deleterious results, including profound shock. The leukotrienes produce severe bronchoconstriction and cause venule dilation and increased vascular permeability. The prostaglandins exaggerate bronchoconstriction and potentiate the effects of histamine on vascular permeability and pulmonary secretions. Kinins contribute to bronchoconstriction, vasodilation, and increased vascular permeability. Eosinophilic chemotactic factor of anaphylaxis (ECFA) is then released to attract eosinophils, which work to neutralize mediators such as histamine, but the amount of neutralization is ineffective in reversing the anaphylaxis. (See Figure 10-1 for a depiction of the pathophysiologic process of anaphylaxis.)

Figure 10-1 Pathophysiologic process of anaphylaxis. (Major chemical mediators are in boldface print.) SRS-A, Slow-reacting substance of anaphylaxis.

Researchers have made a distinction between “true anaphylaxis” and “pseudo-anaphylaxis” or an “anaphylactoid reaction.” The symptoms, treatment, and mortality risk are identical, but “true” anaphylaxis results directly from degranulation of mast cells or basophils mediated by immunoglobulin E (IgE). Pseudo-anaphylaxis results from the other causes. Differential diagnosis is based on studying the allergic reaction.

Assessment: anaphylactic shock

Goal of system assessment

• Assess the symptoms: Assess for ineffective breathing patterns, impaired gas exchange and airway obstruction, along with altered tissue perfusion related to vasodilation and third spaced intravascular fluids. Symptoms vary with means of antigen entry.

• Classify severity of reaction: Should be determined following initial assessment. Treatment must begin immediately; prior to when diagnostic test results are available. Shock may progress rapidly to circulatory collapse and cardiopulmonary arrest if improperly managed.

• Severity of reaction: Varies with the means of antigen entry, the amount absorbed, rate of absorption, and the degree of hypersensitivity. Dramatic symptoms usually develop within minutes and progress rapidly. More rapid onset correlates with more severe symptoms.

• Evaluate effectiveness of prior treatments: Determine patient’s prior treatment regime if asthmatic; classify which “step” of treatment has been needed to control symptoms; patient may need to move to the next step of treatment to maintain control (see Acute Asthma Exacerbation, p 354).

History and risk factors

Recent exposure to:

• Pharmacologic agents: Penicillin, anesthetics, vaccines, contrast media

• Allergenic foods: Seafood, shellfish, nuts, grains, dairy products

• Insect bites or stings: Wasps, hornets, bees, fire ants

• Latex

• Recent blood transfusion

Vital signs

• Pulse oximetry: Oxygen saturation is decreased from patient’s baseline value.

• Tachycardia (heart rate [HR] greater than 140 beats/min [bpm]) and tachypnea (respiratory rate [RR] greater than 40 breaths/min)

• Hypotension may be present; hypotension is exacerbated by underlying vasodilation coupled with increased capillary permeability prompting third spacing of intravascular fluids.

Observation (see table 10-1)

• Red to purple discoloration of face and body; “extreme flushing” with swelling of lips, eyelids, and face due to angioedema

• Tears coming from eyes with strained facial expression

• Severe reactions render patients unable to speak due to breathlessness

• Use of accessory muscles; fatigued, with or without diaphoresis

• Chest expansion may be decreased or restricted.

• Altered level of consciousness (LOC) (confusion, disorientation, agitation)

• Agitation is more commonly associated with hypoxemia while somnolence is associated with hypercarbia (elevated carbon dioxide level).

• General early indicators (occurring within seconds to minutes) include uneasiness, lightheadedness, tingling feeling, flushing, and pruritus.

• General late indicators (occurring within minutes) include rapid progression of urticaria involving large areas of skin; angioedema (tissue swelling; more commonly the eyes, lips, tongue, hands, feet, and genitalia); cough, hoarseness, dyspnea, and respiratory distress; lightheadedness or syncope; and abdominal cramps, diarrhea, and vomiting

• Ingestion of antigen: Cramping, diarrhea, nausea, and vomiting may precede systemic shock symptoms.

• Inhalation of antigen: Cough, hoarseness, wheezing, dyspnea

• Allergic reaction: Edema, urticaria, itching at the site of a bee sting or drug injection

Table 10-1 SYSTEMIC EFFECTS OF ANAPHYLAXIS

System	Effects	Cause
Neurologic	Apprehension; headache; confusion; decreased LOC progressing to coma	Vasodilation; hypoperfusion; cerebral hypoxia or cerebral edema occurring with interstitial fluid shifts
Respiratory	Dyspnea progressing to air hunger and complete respiratory obstruction; hoarseness; noisy breathing; high-pitched, “barking” cough; wheezes; crackles; rhonchi; decreasing breath sounds; pulmonary edema (some patients)	Laryngeal edema; bronchoconstriction; increased pulmonary secretions
Cardiovascular	Decreased BP leading to profound hypotension; increased HR; decreased amplitude of peripheral pulses; palpitations and dysrhythmias (atrial tachycardias, premature atrial beats, atrial fibrillation, premature ventricular beats progressing to ventricular tachycardia, or ventricular fibrillation); lymphadenopathy	Increased vascular permeability; systemic vasodilation; decreased cardiac output with decreased circulating volume; reflex increase in HR; vasogenic shock
Renal	Increased or decreased urine output; incontinence	Decreased renal perfusion; smooth muscle contraction of urinary tract
Gastrointestinal	Nausea, vomiting, diarrhea, abdominal cramping	Smooth muscle contraction of GI tract; increased mucus secretion
Cutaneous	Urticaria; angioedema (hands, lips, face, feet, genitalia); itching; erythema; flushing; cyanosis	Histamine-induced disruption of cutaneous vasculature; vasodilation, increased capillary permeability; decreased oxygen saturation

BP, Blood pressure; HR, heart rate; GI, gastrointestinal; LOC, level of consciousness.

Auscultation

• Wheezing bronchial breath sounds

• Chest may be nearly silent if airflow is severely obstructed.

Palpation

• Palpate to assess for chest expansion; chest may be hyperinflated if patient is asthmatic.

• Decreased tactile fremitus may be present if patient is asthmatic.

Percussion

• May reveal hyperresonance (pneumothorax), a complication of asthma (if present)

Diagnostic Tests for Anaphylaxis

The diagnosis of anaphylaxis is based on presenting signs and symptoms. Treatment should be initiated before laboratory results are available.
Test	Purpose	Abnormal Findings
Arterial blood gas analysis (ABG)	Assess for abnormal gas exchange or compensation for metabolic derangements. Initially, PaO₂ is normal and then decreases as the ventilation-perfusion mismatch becomes more severe.	pH changes: Acidosis may reflect respiratory failure; alkalosis may reflect tachypnea; Carbon dioxide: Elevated CO₂ reflects respiratory failure; decreased CO₂ reflects tachypnea; rising PCO₂ is an ominous sign, since it signals severe hypoventilation which can lead to respiratory arrest. Hypoxemia: PaO₂ <80 mm Hg Oxygen saturation: SaO₂ <92%
Complete blood count (CBC) with WBC differential	WBC differential evaluates the strength of the immune system’s response to the trigger of response	Eosinophils: Increased in patients not receiving corticosteroids; indicative of magnitude of inflammatory response Hematocrit (Hct): May be increased from hypovolemia and hemoconcentration
Tryptase level	Assesses for this chemical mediator released by mast cells following anaphylaxis	Increases within 1 hour following anaphylaxis and remains elevated for 4–6 hours
IgE levels	Used to confirm origin of the reaction is an allergic response	Levels are elevated if allergic response is present.
12-Lead electrocardiogram (ECG)	To detect dysrhythmias reflective of myocardial ischemia	Ischemic changes (ST depression) may be present as shock progresses.

Collaborative management (see figure 10-2)

Figure 10-2 Algorithm for the treatment of acute anaphylaxis.

(From Nicklas RA, et al: The diagnosis and management of anaphylaxis. J Allergy Clin Immunol 101(6 Pt 2):S465–S528, 1998.)

Care priorities

Prevention:

The goal of management of patients with severe allergies is to control the allergic response using a stepped approach to therapies and/or to prevent exposure to the antigen. Ideally, patients should be educated regarding avoidance of the allergen, but for those with severe allergies, avoidance may not be possible for all substances, such as various substances in the air. For asthmatics, ideal control is attained when patients are free of daytime symptoms, do not awaken breathless or coughing at night, and have few or no limitations on activities. For those with allergies to insects, immunotherapy with hymenoptera venoms is used worldwide as an effective treatment for most patients hypersensitive to stings from bees, wasps, hornets, yellow jackets, or white faced hornets or bites from fire ants. A vaccine to prevent anaphylaxis from peanuts and tree nuts shows promise as a way to prevent allergic individuals from developing anaphylaxis. The Food and Drug Administration has not yet approved the vaccine.

When prevention fails, the potential for life-threatening respiratory failure is high during exacerbations unresponsive to treatment within the first hour. Management is directed toward decreasing bronchospasm and increasing ventilation. Other interventions are directed toward treatment of complications.

1. Maintain a patent airway:

Early, rapid endotracheal intubation should be done to manage rapidly progressing laryngeal edema. Severe laryngeal edema may cause complete airway obstruction in minutes. A tracheostomy or an emergency cricothyroidotomy is necessary if endotracheal intubation is not possible.

2. Provide supplemental oxygen:

Administered to support ventilation and aerobic metabolism. Amount and method of oxygen administration are guided by arterial blood gas (ABG) results. Often initiated at 6 L/min via nasal cannula or oxygen mask.

3. Manage vasodilation and increased capillary permeability

a. Epinephrine:

Epinephrine reverses anaphylaxis by increasing myocardial contractility, dilating bronchioles, constricting blood vessels, inhibiting histamine release, and counteracting histamine. Dosage and route vary.

Individuals taking beta adrenergic blocking agents such as propranolol may not respond as rapidly as expected to epinephrine and may require higher or additional dosing. Glucagon may help to counteract the effects of beta-blocking drugs.

• Standard adult dose: 0.2 to 0.5 mg (0.2 to 0.5 ml of a 1:1000 solution) given intramuscularly (IM) or subcutaneously (SC)

• Alternate initial dose: 0.1 mg (0.1 ml of a 1:1000 solution) may be administered.

• Repeat dosage: may be repeated every 10 to 15 minutes as needed

• IV dosage: preferred if patient is in shock and/or has severe airway obstruction: Initial dose of 0.1 to 0.25 mg (1.0 to 2.5 ml of 1:10,000 solution) over 5 to 10 minutes. The dose may be increased to 0.3 to 0.5 mg. Repeat every 5 to 15 minutes as needed.

• IV infusion: after initial dose, an IV drip of epinephrine 1.0 mg in 250 ml D₅W may be infused at 1 mcg/min and increased to 4 mcg/min (or more) as needed to achieve desired response.

• Endotracheal (ET) tube: 1.0 to 2.5 ml of 1:10,000 solution (1 mg epinephrine in 10-ml solution) into ET tube, followed by use of manual resuscitation (Ambu) bag. May repeat if needed.

b. Fluid resuscitation:

IV crystalloids (e.g., lactated Ringer, 0.9% normal saline) and/or colloids (e.g., albumin and plasma protein fraction) to increase intravascular volume. Colloids increase colloid osmotic pressure to help retain fluid in the blood vessels. May require rapid infusion of 2 to 3 L of fluids.

c. Vasopressors:

Used if fluid replacement does not increase blood pressure (BP). Drugs are titrated for the desired response (see Appendix 6). Usual dosages are as follows:

• Dopamine hydrochloride: Effects are dose dependent. Increases cardiac contractility at 5 to 10 mcg/kg/min and systemic vascular resistance at 10 to 20 mcg/kg/min. Consider switching to norepinephrine if dose exceeds 20 mcg/kg/min.

• Norepinephrine: Initial dosage is 2 to 8 mcg/min and can be increased to achieve the necessary BP.

• Phenylephrine: Usual dosage is 40 to 60 mcg/min. Doses exceeding 200 mcg/min have been used.

d. Antihistamines:

Diphenhydramine: Usual dose is 20 to 50 mg, but 50 to 100 mg may be given IV or IM to relieve urticaria and abdominal cramping. IV H₂-antagonists (e.g., cimetidine, ranitidine) are also used.

e. Corticosteroids:

Used to help decrease release of chemical mediators that increase capillary permeability. Hydrocortisone sodium succinate: loading dose is 100 to 1000 mg IV; or methylprednisolone sodium succinate: loading dose is 125 to 250 mg IV. Followed by IV or oral (PO) corticosteroids for several days.

f. Inhaled bronchodilators (e.g., albuterol):

May be given for continued bronchospasm (see Acute Asthma Exacerbation, p. 354).

g. Glucagon IV bolus:

Use is controversial for counteracting effects of beta-blocking drugs or for other patients who have limited response to treatment. Relaxes smooth muscle and increases HR and force of contraction.

4. Ecg monitoring:

To detect dysrhythmias

CARE PLANS FOR ANAPHYLAXIS AND ANAPHYLACTIC SHOCK

Ineffective airway clearance

Goals/outcomes

Within 20 minutes of treatment/intervention, patient has adequate spontaneous tidal and expiratory volumes as evidenced by easier breathing; audible breath sounds in expected range, and no adventitious breath sounds.

Respiratory Status: Ventilation, Vital Signs Status, Respiratory Status: Airway Patency, Symptom Control Behavior, Comfort Level, Endurance

Airway management

1. Assess continuously for obstructed airway and increased respiratory effort: Note increased pulmonary secretions, cough, expiratory wheezing, SOB, and dyspnea. Suction as needed. Caution: An oral airway provides airway support only as far as the posterior pharynx. If laryngeal edema is present, the oral airway cannot relieve symptoms because the obstruction is below the oral airway. If ET intubation is attempted and is not possible due to laryngeal edema, prepare for tracheostomy or cricothyroidotomy.

2. Monitor for decreased breath sounds or changes in wheezing at frequent intervals: Absent breath sounds in a distressed patient may indicate impending respiratory arrest. Identify patient requiring actual/potential airway insertion. Consult physician and prepare for ET intubation if lingual edema is present and/or respiratory distress continues.

3. Position patient for comfort and to promote optimal gas exchange: High Fowler’s position, with the patient leaning forward and elbows propped on the over-the-bed table to promote maximal chest excursion, may reduce use of accessory muscles and diaphoresis due to work of breathing. May not be possible with severe hypotension, as further decrease in BP may result.

Ventilation assistance

1. Monitor for signs of increasing hypoxia at frequent intervals: Restlessness, agitation, and personality changes are indicative of severe reaction. Cyanosis of the lips (central) and nail beds (peripheral) are late indicators of hypoxia, but may be difficult to see with severe angioedema.

2. Monitor for signs of hypercapnia at frequent intervals: Confusion, listlessness, and somnolence are indicative of respiratory failure.

3. Provide medications to abate allergic response: Administer epinephrine and IV and inhaled bronchodilators as appropriate to attain control of deterioration.

Airway Insertion and Stabilization; Airway Management; Anaphylaxis Management; Medication Administration, Medication Management, Respiratory Monitoring

Impaired gas exchange

Goals/outcomes

Within 20 minutes of initiation of treatment/intervention, patient has adequate alveolar exchange of CO₂ or O₂ as evidenced by easier breathing, PaO₂ 80 mm Hg or greater, and SpO₂ 90% or greater.

Respiratory Status: Ventilation

Anaphylaxis management

1. Monitor FIO₂ to ensure that oxygen is within prescribed concentrations. If patient does not retain carbon dioxide, 100% nonrebreather mask may be used to provide maximal oxygen support. If the patient retains CO₂ and is unrelieved by positioning, lower-dose oxygen, bronchodilators and steroids, intubation, and mechanical ventilation may be necessary sooner than in patients who are able to receive higher doses of oxygen by mask.

2. Monitor ABGs when continuous pulse oximetry values or patient assessment reflects progressive hypoxemia or development of hypercapnia. Monitor and report ABG values with increasing PaCO₂ (greater than 50 mm Hg) or decreasing PaO₂ (less than 60 mm Hg) indicative of impending respiratory failure.

3. Administer antihistamines as prescribed.

4. Administer glucocorticoids as prescribed.

5. Position patient to alleviate dyspnea (assist patient to sitting position if BP is stable).

6. Stay with patient to promote safety and reduce fear. Use calm, reassuring approach.

Respiratory Monitoring; Emotional Support; Medication Administration, Medication Management

Decreased cardiac output

Goals/outcomes

Within 4 hours of initiation of treatment, patient has adequate cardiac output (CO) as evidenced by BP 90/60 mm Hg or greater, strong peripheral pulses, CO 4 L/min or greater, CI 2.5 L/min/m² or greater, SVR 900 dynes/sec/cm⁻⁵ or greater, urinary output 0.5 ml/kg/hr or greater, and normal sinus rhythm on ECG.

Circulation Status; Tissue Perfusion: Cardiac; Vital Signs

Hemodynamic regulation

1. Assess for physical and hemodynamic indicators of decreased cardiac output:

• Palpate peripheral pulses for decreasing amplitude.

• Assess arterial BP or MAP for any decrease, an indicator of failed compensatory mechanisms.

• Monitor SVR. A decrease (less than 800 dynes/sec/cm⁻⁵) is associated with decreased afterload (vasodilation) and may precipitate decreased CO.

• Monitor CO, ScVO2 and cardiac index if available. A CI of less than 2.0 L/min/m² and ScVO2 less than 80% are usually associated with hypoperfusion.

• Hemodynamic measurements: As vasogenic shock evolves, decreased arterial BP, mean arterial pressure (MAP), CO (less than 4 L/min), CI (less than 2.5 L/min), systemic vascular resistance (SVR) (less than 800 dynes/sec/cm⁻⁵), and pulmonary artery wedge pressure (PAWP) (less than 5 mm Hg) are present from worsening vasodilation, progressive shifting of intravascular fluid to interstitial spaces, and decreasing venous return.

2. Monitor for dysrhythmias, such as atrial tachycardias, PVCs, ventricular tachycardia, and ventricular fibrillation, which may signal hypoxemia or occur as side effects of drugs such as aminophylline or epinephrine.

3. Monitor for increases and decreases in edema.

Continued swelling, despite treatment, may indicate ineffective treatment, overaggressive fluid therapy, or heart or kidney failure.

4. Administer epinephrine as prescribed. Observe for therapeutic effects as evidenced by increased SVR, increased CO/CI, increased ScVO2, increased arterial BP and MAP, stronger peripheral pulses, warming of extremities, and increased urine output.

5. Administer fluid replacement therapy as prescribed, using a large-bore IV catheter. Colloids and crystalloids may be given together.

During fluid resuscitation, assess patient for indicators of fluid volume excess, including crackles with chest auscultation, presence of S₃ heart sounds, and jugular venous distention. If hemodynamic monitoring lines are present, be alert to increasing PAP, PAWP, and right atrial pressure (RAP).

6. Prepare for possible vasopressor infusion if hypotension persists after fluid resuscitation and epinephrine administration.

Anaphylaxis Management; Hypovolemia Management; Medication Administration, Medication Management, Cardiac Care: Acute

Altered tissue perfusion: peripheral, renal, and cerebral

Goals/outcomes

Within 4 hours of initiation of treatment, patient has adequate perfusion as evidenced by strong proximal peripheral pulses, brisk capillary refill, warm extremities temperature, urinary output 0.5 ml/kg/hr or greater, uncompromised neurologic status, and no restlessness, listlessness, and unexplained anxiety.

Tissue Perfusion: Abdominal Organs, Tissue Perfusion: Peripheral; Tissue Perfusion: Cerebral

Hypovolemia management

1. Assess peripheral pulses. Report decreased amplitude of pulses.

2. Assess capillary refill. Delayed capillary refill (greater than 2 seconds) is likely with edema and decreased vascular volume.

3. Assess degree of peripheral edema.

4. Assess color and warmth of extremities. Report presence of coolness and pallor.

5. Monitor BP at frequent intervals. Be alert for indicators of hypotension such as BP readings greater than 20 mm Hg below patient’s normal pressure, dizziness, restlessness, altered mentation, and decreased urinary output.

6. Monitor urine output hourly. Continuous CO monitoring using a noninvasive system or a pulmonary artery catheter may be needed to guide fluid resuscitation.

7. Observe for indicators of decreased cerebral perfusion such as anxiety, restlessness, confusion, and decreased LOC.

HIGH ALERT!

Changes in LOC may signal either decreased cerebral perfusion (tissue hypoxia) or increasing intracranial pressure (IICP) caused by interstitial swelling from capillary permeability.

8. Administer fluid and pharmacologic agents as prescribed (see previous nursing diagnosis).

Hemodynamic Regulation; Anaphylaxis Management; Medication Administration, Medication Management

Deficient knowledge illness care: severe hypersensitivity reaction, its causes, and its symptoms

Goals/outcomes

By the time of discharge from the critical care unit, patient demonstrates increased knowledge of severe hypersensitivity reactions as evidenced by verbalization of potential causative factors, symptoms of allergic reaction, need to inform health care providers of allergies, importance of wearing medical-alert identification, prescribed treatment modalities when in contact with allergen, and the necessity of informing primary health care provider immediately of any allergic symptoms.

Knowledge: Treatment Regimen; Knowledge: Illness Care; Knowledge: Health Behavior; Knowledge: Disease Process

Teaching: disease process

1. Provide information about the antigenic agent that caused the anaphylaxis, including ways to avoid it in the future.

2. Explain need for wearing a medical-alert identification tag or bracelet to identify the allergy.

3. Give information about anaphylaxis emergency treatment kits. Teach patient self-administration technique and the importance of prompt treatment.

4. Stress the importance of seeking treatment immediately if symptoms of allergy occur, including flushing, warmth, itching, anxiety, and hives.

5. Explain the importance of identifying and checking all over-the-counter (OTC) medications for the presence of potential allergens.

Health Education; Risk Identification; Teaching: Prescribed Medication

Additional nursing diagnoses

Also see nursing diagnoses and interventions in Hemodynamic Monitoring (p. 75), Emotional and Spiritual Support of the Patient and Significant Others (p. 200), and Mechanical Ventilation (p. 99).

Profound anemia and hemolytic crisis

Pathophysiology

Anemia

Anemia reflects a reduction in total body hemoglobin (Hgb) concentration and is common in critically ill patients. By the third day in an intensive care unit (ICU), 95% of patients have reduced Hgb concentrations. As the Hgb decreases, the oxygen-carrying capacity of the blood is reduced, resulting in tissue hypoxia unless compensatory mechanisms are adequate to assist the body with oxygen delivery. Anemia may be classified under one of three functional classes after initial evaluation of the CBC and reticulocyte index. (See Table 10-2 for functional classification.)

Table 10-2 FUNCTIONAL CLASSES OF ANEMIA WITH EXAMPLES

Blood Loss/Hemolysis	Decreased RBC Production	Maturation Disorders
Autoimmune diseases Thrombotic Thrombocytopenia Purpura (TTP), Goodpasture’s Syndrome, Systemic Lupus Erythematosus (SLE), Wegener’s Granulomatosis	Damaged bone marrow: malignancy, lead poisoning, aplastic/hypoplastic anemia, chemotherapy, viruses	Abnormal RBC cytoplasm Phenylketonuria (PKU), G6PD
Abnormal hemoglobin Sickle cell disease, Hgb S, C D, E	Iron deficiency: malignancy, autoimmune disorders	Abnormal RBC nucleus
Abnormal RBC membranes Spherocytosis, hemolytic uremic syndrome, paroxysmal nocturnal hematuria	Erythropoietin deficiency: renal failure, malaria, thalassemias	Iron deficiency: dietary, chronic alcoholism
Bleeding/hemorrhage Physical trauma to blood (bypass, balloon, valves), antibodies (drug-induced antibodies), endotoxins (malaria, clostridia), GI bleed, trauma, rupture, excess menstruation	Inflammation/infection: chronic inflammatory disease; critical illness
Excessive phlebotomies: lab sampling	Metabolic disturbance: pernicious anemia, hypothyroidism, megaloblastic anemia

Hemolytic crisis

Hemolytic crisis is an acute disorder that frequently accompanies hemolytic anemias. It is characterized by premature pathologic destruction (hemolysis) of red blood cells (RBCs). As RBC destruction accelerates, the oxygen-carrying capacity of the blood decreases, which results in a reduction in the amount of oxygen delivered to the tissues. This hypoxic state produces tissue ischemia and can progress to tissue infarction. Hemolytic episodes can be triggered by both emotional and physiologic states, including stress, trauma, surgery, acute infectious processes, and abnormal immune responses.

Assessment

Goal of system assessment

Evaluate for decreased oxygen-carrying capacity with subsequent organ dysfunction due to decreased production or increased destruction or loss of RBCs.

Anemia

Risk factors:

Advanced age; environmental exposure to certain chemicals, liver dysfunction, autoimmune or other immunologic disorders, malignancy (and its treatment), drug use (such as aspirin, NSAIDs, warfarin); diets low in protein and iron, iron or folic acid deficiency, B12 deficiency, chronic alcoholism, autoimmune disorders

Clinical presentation (chronic indicators)

• Pallor, melena, hematochezia, fatigue, weight loss, dyspnea on exertion, uremia, sensitivity to cold, intermittent dizziness, excessive menstruation, paresthesias

• Chronic hemolytic anemia: Jaundice, renal failure, hematuria, arthritis, increased incidence of gallstones, skin ulcers

Clinical presentation (acute indicators)

• Fever, chest pain, acute heart failure, confusion, irritability, tachycardia, orthostatic hypotension, dyspnea, tachypnea, frank bleeding, critical illness for longer than 3 days

Vital signs

• Tachypnea, orthopnea, tachycardia, fever

Observation

• Altered mental status, unusual fatigue or weakness

• Spider angiomas, unusual bleeding (i.e., stool, urine, emesis)

• Electrocardiogram (ECG) changes

• Monoarticular or polyarticular arthritis

• Smooth tongue, skin ulcers

Palpation

• Bone tenderness (especially rib and sternal areas), joint tenderness

• Enlargement of the liver and/or spleen

Auscultation

• Crackles associated with heart failure

Hemolytic crisis

Risk factors:

Individuals with mild or chronic hemolytic anemia may be asymptomatic until they are exposed to a severe stressor, such as an acute infectious process, profound emotional upset, critical illness, surgery, or trauma. With added stress, hemolysis can accelerate to a crisis state in which patients experience organ congestion from massive amounts of hemolyzed blood cells, precipitating multiple organ dysfunction syndrome (MODS) and shock.

Clinical presentation (acute):

Fever; abdominal, chest, joint, and back pain; jaundice; headache; dizziness; palpitations; shortness of breath (SOB); hemoglobinuria; lymphadenopathy; splenomegaly; and signs of peripheral nerve damage including paresthesias, paralysis, chills, and vomiting

Clinical presentation (chronic):

Anemia; pallor; fatigue; dyspnea on exertion; mentation changes; icterus; bone infarctions; monoarticular and polyarticular arthritis; hematuria; renal failure; increased gallstone formation; skin ulcers and itching

Vital signs

• Tachypnea, tachycardia, hypertension

Observation

• Impaired growth and development, depending on severity and duration of anemia

• Jaundice; retinal detachment and associated vitreous hemorrhage

• SOB, with dyspnea on exertion

• Monoarticular or polyarticular arthritis

• Hemiplegia, paresthesias

Palpation

• Splenomegaly, hepatomegaly, lymphadenopathy or abdominal guarding

• Chronic skin ulcers, particularly in the ankle area

Auscultation

• Crackles associated with heart failure

• Murmurs related to valvular damage

Diagnostic Tests for Anemias and Hemolytic Crisis

Test	Purpose	Abnormal Findings
Red blood cell count (RBCs)	Enumeration of the red cells found in each cubic millimeter of blood	Reduced; in hemolytic crisis, an increased number of premature RBCs (nucleated RBCs) will be present.
Hemoglobin (Hgb)	Hemoglobin content of RBCs	Decreased
Hematocrit (Hct)	Percentage of RBCs in relation to total blood volume	Decreased
Reticulocyte count, reticulocyte index, corrected reticulocyte	RBC precursors; measures how fast RBCs are produced in the bone marrow	Elevated: because of increased bone marrow production of RBCs due to blood loss or RBC destruction; also a sign of marrow recovery after chemotherapy.
Mean corpuscular volume (MCV) (subcategory of red cell indices) Macrocytic: MCV >100 mcg³ Microcytic: MCV <80 mcg³ Normocytic: MCV 80–100 mcg³	Morphologic classification of RBCs: average size of individual RBCs. Obtained by dividing HCT by total RBC count	Low in microcytic anemia; high in macrocytic anemia
Sickle cell test	Indicative of sickle cell anemia (trait, disease)	Presence of Hemoglobin S (Hgb S)
Hemoglobin (Hgb) electrophoresis	Screens for abnormal hemoglobins often present in hemolytic anemias Many hemoglobinopathies are interrelated. Disease expression is based on the degree of genetic abnormalities. Various combinations of abnormal hemoglobins are possible	Hemoglobins A₁, A₂, and F: Normal Hgb Hemoglobin C: Generally benign; May cause joint pain, splenomegaly and gallstones; may protect against malaria Hemoglobins D and E: Rarely occur “singly”; sometimes present with sickle cell disease or thalassemias Hemoglobin H: Causes premature destruction of RBCs and abnormal binding of O₂ to RBCs; causes alpha thallasemia Hemoglobin S: Most common abnormal hemoglobin, occurring in 10% of the African American population; causes sickle cell disease or sickle cell trait
Erythrocyte sedimentation rate (ESR), sedimentation rate or Biernacki reaction	Rate at which RBCs precipitate in a period of 1 hour: nonspecific measure of inflammation	Elevated in hemolytic anemia; decreased in sickle cell anemia, polycythemia and congestive heart failure
C₃ proactivator	Proactivator of complement 3 in the alternate pathway of complement activation	Increased in hemolytic anemia
Total iron-binding capacity (TIBC)	Measures the blood’s capacity to bind iron with transferrin; also indirect test of liver function (rarely used for that) TIBC is typically measured along with serum iron to evaluate people suspected of having either iron deficiency or iron overload.	Normal or reduced, depending on the type of anemia
Ferritin	Iron stores: with damage to organs that contain ferritin (especially the liver, spleen, and bone marrow), ferritin levels can become elevated even though the total amount of iron in the body is normal.	Reduced with iron deficiency anemia; normal or elevated with anemia of critical illness; elevated with hemachromatosis
Transferrin	Used to determine the cause of anemia, to examine iron metabolism (for example, in iron deficiency anemia) and to determine the iron-carrying capacity of the blood.	Reduced with anemia of chronic inflammation, anemia of critical illness.
Transferrin saturation	The iron concentration divided by TIBC—a more useful indicator of iron status than iron or TIBC alone.	Reduced with anemia of chronic inflammation, anemia of critical illness.
Folate; folic acid	Measures folic acid in the blood	Reduced with nutritional deficiency leading to megaloblastic anemia.
Erythropoietin (EPO, EP)	Measures the amount of a hormone called erythropoietin (EPO) in blood; acts on stem cells in the bone marrow to increase the production of red blood cells; made by cells in the kidney, which release the hormone when oxygen levels are low.	Reduced with renal disease and normal in those who are critically ill who should have an elevated level if anemia of any cause is present. Reticulocyte response to EP has been shown to be reduced in many critically ill patients with elevated EP levels.
Vitamin B₁₂	Measures the amount of vitamin B₁₂ in the blood; used with folic acid test, because a lack of either can cause megaloblastic anemia.	Reduced with pernicious or megaloblastic anemia.
Unconjugated bilirubin: free bilirubin, indirect bilirubin	Measures bilirubin that has not been conjugated in the liver. It gives an indirect reaction to the Van Den Bergh test.	Elevated in hemolytic anemia due to liver’s inability to process increasing bilirubin released during hemolysis.
Serum lactic dehydrogenase isoenzymes (LDH₁ and LDH₂ )	General indicator of the existence and severity of acute or chronic tissue damage and, sometimes, as a monitor of progressive conditions; monitor damage caused by muscle trauma or injury and to help identify hemolytic anemia	Elevated in hemolytic anemia because of their release when an RBC is destroyed.
Haptoglobin level	Used to detect and evaluate hemolytic anemia; not to diagnose cause of the hemolysis. Haptoglobin levels should be drawn prior to transfusion.	Decreased in hemolytic anemia due to increased binding of haptoglobin, which facilitates removal of increased Hgb from blood.
Peripheral blood smear	Microscopic examination of cells from drop of blood; investigates hematologic problems or parasites such as malaria and filaria	May reveal abnormally shaped RBCs, such as spherocytes. RBC hyperplasia (abnormal number) is present in nearly all cases of chronic hemolysis with intact bone marrow.
Bone marrow aspiration	Evaluates bone marrow status; diagnose blood disorders and determine if cancer or infection has spread to the bone marrow.	May reveal abnormal size, shape, or amounts of RBCs, WBCs or platelets
Coombs test: Direct antiglobulin test; Indirect antiglobulin test	Detects antibodies that may bind to RBCs and cause premature RBC destruction	Positive in antibody-mediated immunologic hemolysis.
Immunoglobulin levels	Measures the level of immunoglobulins, also known as antibodies, in the blood.	Elevated: autoimmune disorders, sickle cell; lower in immunocompromised states.
Glucose-6-phosphate dehydrogenase (G6PD) levels	Measures G6PD—enzyme levels are normal in newly produced cells but fall as RBCs age and only deficient cells are destroyed.	Decreased in G6PD deficiency, hemolysis Elevated: MI, liver failure, chronic blood loss, hyperthyroidism
Radiologic examinations	X-rays and bone scans Liver/spleen scans	Decreased density, aseptic necrosis of bones Hepatomegaly, splenomegaly, lesions