Introduction
Dyspnea is a common and debilitating symptom of advanced cancer patients and is typically difficult to manage. Dyspnea affects 21-78.6 percent of advanced cancer patients, with 10-63 percent experiencing moderate to severe symptoms; as the disease progresses and death approaches, the frequency and severity of dyspnea increase. Individuals with lung cancer who experience dyspnea have a worse survival rate than patients with other forms of cancer. Dyspnea can be a direct result of cancer, a side effect of therapy, or unrelated to cancer or treatment. Patients may also have the following conditions:
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Chronic obstructive lung disease.
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Congestive heart failure.
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Nonmalignant pleural effusion.
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Pneumonitis.
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Airflow blockage.
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Bronchospasm associated with asthma.
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Malignancy.
In addition, dyspnea may be a clinical manifestation of extreme cachexia (loss of muscle weight) without lung or cardiac disease and asthenia (weakness of the body) or severe asthenia.
What Are the Causes of Dyspnea?
Dyspnea is an unpleasant subjective feeling that cannot be described by the physical abnormalities accompanying it. However, pathophysiologically, dyspnea can be caused by three significant abnormalities:
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An increase in a respiratory effort to overcome a specific load (e.g., restrictive, obstructive lung disease, pleural effusion).
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An increase in the proportion of respiratory muscle required to maintain an average workload (e.g., cancer cachexia and neuromuscular weakness)
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An increase in ventilator requirements such as hyperemia (increased body temperature), metabolic acidosis (disturbances in the body pH levels), hypercapnia (increased level of carbon dioxide), and anemia (decreased hemoglobin). Different proportions of the three anomalies may co-exist in many cancer patients, complicating the pathophysiological interpretation of dyspnea severity.
Does Dyspnea Occur in Malnourished People?
Malnutrition has been reported to diminish respiratory muscle strength and maximum voluntary breathing in chronically malnourished people without pulmonary illness, so malnutrition may impair the ability of the respiratory muscle to handle the increase in cardiopulmonary illness and ventilator loads. Dyspnea may be a clinical manifestation of severe cachexia and asthenia caused by malignancy. This group has a high prevalence of evaluating these patients, including periodic pulmonary function tests, which can help.
How Is Dyspnea Diagnosed in Cancer Patients?
While some studies have shown a strong association between abnormalities in pulmonary function tests and the degree of subjective dyspnea. The aim of dyspnea evaluation and therapy, as with other symptoms, is the patient's statement of intensity. Both are anticipated to differ significantly.
As a result, the intensity of dyspnea in a given patient is a multidimensional complex that results from the interaction of factors that modulate its production (e.g., severity and acuity of underlying pathophysiology), perception (i.e., cognition, mood, descending inhibitory pathways), and expression (i.e., cultural, beliefs, etc.). While pharmaceutical therapies can help with certain aspects of symptom expression, expressive or supportive psychotherapy, occupational therapy, or physiotherapy can help with others. Only a systematic evaluation that includes all relevant dimensions can evaluate the relative contribution of each component to the overall symptom manifestation.
How Can Dyspnea Be Treated in Cancer Patients?
There are several reasons for a patient. Radiotherapy and chemotherapy may reduce dyspnea in people who do not obtain an objective response. Symptomatic therapies are recommended in addition to specialized treatment for underlying malignancy and pulmonary and cardiovascular disorders. Oxygen therapy is helpful in both hypoxemic and nonhypoxic individuals.
The relevance of transfusion therapy in treating anemia-related dyspnea in advanced and terminal cancer patients remains debatable. In these individuals, oral, intravenous opioids and subcutaneous are efficacious but underutilized. Now the therapeutic use of nebulized opioids is not recommended. At the same time, benzodiazepines are commonly used in patients with dyspnea. Supportive counseling, occupational therapy, or physiotherapy can help with symptom manifestation.
How Is Dyspnea in Advanced Cancer Treated?
Patients with advanced cancer are more likely to have thromboembolic consequences, such as pulmonary embolism. Parenteral anticoagulation is frequently effective in these individuals. Various risk factors, such as smoking, and the toxic effects of antineoplastic drugs and radiation treatment on the mediastinum, including the heart, may result in other cardiovascular problems, including congestive heart failure (CHF).
Other disorders linked with dyspnea include lung infections, which kill almost half of all advanced cancer patients, metabolic acidosis, significant ascites, sudden aggravation of chronic asthma, or an acute panic episode marked by hypoventilation. In all of these cases, prescribing appropriate medicine might result in immediate remission of the symptoms.
What Is the Role of Bronchodilators in Cancer Patients With Dyspnea?
As many lung cancer patients have indications of air flow blockage. Thus, bronchodilator medication is warranted in them. Congestive obstructive pulmonary disorder (COPD) medicine is comparable to asthma pharmacotherapy. In COPD, however, beta2-agonists generate reduced bronchodilation. Furthermore, there is little evidence that frequent bronchodilation affects the natural history of COPD. As a result, in a patient with intermittent symptoms, it is generally best to utilize a beta2-selective bronchodilator when dyspnea is present. Aminophylline, Theophylline, and caffeine have all been shown to increase diaphragmatic contractility in both healthy volunteers and COPD patients. Furthermore, Theophylline activates the respiratory center, enhancing cardiac output, decreasing pulmonary vascular resistance, and lowering blood pressure.
Conclusion
Dyspnea is a common condition to occur in cancer patients. If there is no apparent underlying cause, therapy for dyspnea focuses on symptom relief and quality of life. Some drugs can assist, such as opioids for pain, benzodiazepines for anxiety, and steroids for inflammation, that may be prescribed based on the intensity of the suffering. In addition, cognitive behavioral therapy, as well as teaching new techniques of breathing that might relieve discomforts, such as pursed lip breathing, relaxed body alignment for most short breathing, and timed breathing, can be beneficial—other potential alternatives for breathing assistance range from nebulizer treatments to noninvasive positive pressure ventilation and high-flow oxygen. While breathing and the effects of various pathologic diseases on respiratory function and gas exchange are well recognized, the genesis and pathophysiology of dyspnea as a symptom are far less so. Therefore, the assessment of palliative treatment should focus on dyspnea as a symptom rather than functional and gas exchange problems.
