Cancer-related fatigue is a persistent, subjective sense of tiredness related to cancer or cancer treatment that interferes with usual functioning (Mock et al., 2003).

A. Fatigue is the most commonly reported distressful symptom experienced by cancer patients and may be a side effect of the cancer diagnosis, the treatments, or the pathologic disease process (Ahlberg, Ekman, Gaston-Johansson & Mock, 2003).

B. Fatigue is a subjective experience that is best described by the person experiencing it.

Multiple interacting physiologic, psychological, and situational factors affect the fatigue experience of cancer patients. Some factors known to contribute to fatigue in patients with cancer are listed below.

A. Malnutrition: Hypermetabolism may result from tumor growth and from competition of normal tissue with tumors for nutrients. Hypermetabolism increases nutrient requirements, whereas malabsorption, anorexia, nausea, or vomiting may lead to inadequate intake of nutrients.

B. Lack of Adequate Sleep and Rest: This may be a consequence of pain, anxiety, depression, or cancer treatments.

C. Altered Body Chemistry: An accumulation of toxic byproducts of cellular destruction may result from radiotherapy, chemotherapy, biotherapy, and tumor growth.

D. Emotional Distress: Emotional responses to the uncertain future that accompanies a cancer diagnosis include anxiety and depression, both of which are characterized by fatigue.

E. Oxygen Deficit: Anemia or alterations in oxygen/carbon dioxide exchange (such as those caused by lobectomy or lung disease) may cause hypoxia and fatigue.

F. Deconditioning: Prolonged inactivity related to pain, nausea, or other symptoms may result in a decrease in functional capacity and tolerance for physical activity.

G. Physiologic Alterations: Infection, pain, hypercalcemia, hypoglycemia, and other side effects of treatment or disease alter energy and stamina.

A. Assessment

1. The following are defining characteristics that may indicate fatigue.

a. Verbalization of an unremitting and overwhelming lack of energy or need for rest

b. Inability to maintain usual routines

c. Perceived need for additional energy to accomplish routine tasks; weakness

d. Increase in physical complaints

e. Emotional lability or irritability

f. Impaired ability to concentrate; lethargy or listlessness

g. Decreased ability to perform physical and mental work or feeling accident prone

h. Disinterest in surroundings or introspection

i. Muscle weakness

2. If fatigue is suspected, a comprehensive physical and emotional assessment of the patient should be performed.

a. Note pattern of fatigue: intensity, duration, time of occurrence (AM versus PM), degree of distress, and any other factors that seem to precipitate, increase, or alleviate fatigue.

b. Observe ability to engage in usual activities. Decreases in tolerance for physical activities and impaired ability to concentrate are common characteristics of fatigue.

c. Assess signs and symptoms of concurrent health problems. Disease-related anemia, dyspnea, pain, or tachycardia may contribute to fatigue.

d. Evaluate patterns of rest and sleep. Insomnia, lethargy, and irritability may indicate inadequate sleep. Excessive resting may reflect a decreased tolerance for activity.

e. Observe coping ability. Anxiety, depression, worry, and stress are commonly seen in conjunction with fatigue.

f. Assess alterations in lifestyle and quality of life, as they have been reported to contribute to fatigue.

B. Diagnostic Parameters

1. The clinical diagnosis of fatigue is based on the presence of the defining characteristics listed in the Assessment section of this chapter. There are no accepted serum or laboratory tests for fatigue.

2. A visual analogue scale, similar to that commonly used for clinical assessment of pain, with anchors of “0—No fatigue” to “10—Worst fatigue imaginable,” may be used for a quick clinical assessment of fatigue or to monitor fatigue levels. The rating also suggests how debilitating the symptoms are considered by the patient. Consistent ratings of 4 and above should prompt the care provider to perform a comprehensive assessment and plan appropriate interventions (Mock et al., 2003).

C. Treatment: There are no specific medical treatments for fatigue. However, other medical conditions that contribute to fatigue (eg, anemia, depression) should be treated appropriately. Complaints of fatigue may be indicative of problems listed in section II. See nursing interventions below to help manage fatigue.