Recently, our palliative care service at Roswell Park Cancer Institute was called to see a patient for respiratory distress. The patient was a 55-year-old woman with a history of metastatic breast cancer involving bone and lung tissues. The patient had been admitted to a community hospital for complaints of shortness of breath, disorientation and generalized weakness.
Margaret M. Eberl
A chest X-ray showed right upper lobe consolidation, bilateral infiltrates and a moderate right pleural effusion. Intravenous fluids and antibiotics were begun and the patient was transferred to our institution and soon required intubation and transfer to the ICU. After two days in the ICU, the patient was successfully weaned from the ventilator and transferred to the floor.
Three days later the patient again developed respiratory distress, desaturating to the 70s on 100% fraction of inspired oxygen via nonre-breather face mask. Upon arrival, our team found the patient to be alert and able to communicate her needs, but clearly with increased work of breathing. The patient expressed her desire to be made more comfortable, but not intubated or resuscitated. We assured the patient and her significant other we would provide medications to ease her distress.
After a trial of oral morphine and IV lorazepam, the patient continued to be tachypneic. A continuous infusion of morphine was titrated up to 7 mg/hour. Breathing comfortably, the patient passed away several hours later.
According to the Handbook of Palliative Care in Cancer, dyspnea is the unpleasant sensation of shortness of breath. About 70% of cancer patients will develop dyspnea during the last six weeks of life. Life expectancy appears to have an inverse relationship with the presence of dyspnea. In the cancer patient, dyspnea can be caused by the malignancy itself, therapies, comorbid medical conditions, as well as general muscle weakness/wasting. As in this patient, dyspnea is common in patients with advanced lung cancer and in malignancies involving lung/pleural metastases. Pleural effusion, ascites, superior vena cava syndrome and lymphangitic carcinomatosis are other typical causes.
Cancer therapies, including pneumonectomy, radiation with subsequent radiation fibrosis in the lung, and chemotherapy induced changes (particularly second to bleomycin) may also produce dyspnea. The medical causes of dyspnea are broad: chronic obstructive pulmonary disease, asthma, pulmonary embolus, left heart failure, pulmonary edema, pneumonia and anemia can similarly cause or contribute to dyspnea in the cancer patient. In addition, dyspnea can result from, or be worsened by, the presence of anxiety, depression and other psychological illness. Table 1 presents some potential causes of dyspnea and evidence-based treatment strategies.
As a subjective symptom, dyspnea and its severity can only be reported by the patient. Symptom intensity can be assessed using a numerical scale(0-10) or a tool such as that offered by the Edmonton model (www.palliative.org/PC/ClinicalInfo/AssessmentTools/AssessmentToolsIDX.html). However, it is often impractical to use such tools in an acute care setting. Physical signs of distress associated with dyspnea may leave patients unable to communicate. Patients with dyspnea may or may not exhibit hypoxia; moreover, measurement of oxygen saturation with pulse oximetry does not always reflect a patients experience of dyspnea. Physical assessment of dyspnea includes auscultation of breath sounds and measurement of heart rate, respiratory rate, jugular pressure and functional status.
The National Comprehensive Cancer Network recommends considering patient life expectancy when managing cancer patients with dyspnea. For those patients with years, years to months, or months to weeks to live, underlying causes of dyspnea can be sought and treated. Ventilatory support with continuous positive airway pressure and bilevel positive airway pressure may be provided temporarily for reversible conditions. In dying patients with a life expectancy of weeks to days, the focus of management may shift to assuring comfort, relieving symptoms, providing anticipatory guidance about the dying process to the patient and family and assuring continuous emotional support.
It is important to understand that dyspnea can be a frightening symptom for the patient and their family. Patients often attribute various meanings to this symptom, and by determining these meanings clinicians can educate and reassure the patient and their family.
In addition to reassurance, several other nonpharmacologic therapies can be undertaken. These include determining the most comfortable position for the patient (often with head and torso elevated or with the affected lung facing down) and improving air circulation (ie, opening windows, using a table fan/humidifier and eliminating respiratory irritants such as tobacco smoke). If dyspnea is causing anxiety (or vice versa), limiting the number of visitors in the patients room and playing soft music can help create a calm environment. Breathing retraining (pursed lip breathing), relaxation techniques, massage and prayer can also be performed.
Depending on the underlying cause of dyspnea in the cancer patient, oxygen and/or pharmacologic therapy can be offered. About 50% of cancer patients have more than one etiology for their dyspnea. Supplemental oxygen is indicated if the patient is hypoxic, with nasal cannula as the preferred method of delivery. To establish hypoxemia, pulse oximetry is preferable to an arterial blood gas as it is noninvasive and not painful. Oxygen may have a placebo effect of providing a sense of comfort to the patient.
If medication is required, opioids are the main therapy recommended for the management of dyspnea. In the opiate naive patient, an oral opioid, such as morphine (typical starting dose 5 mg) can be provided every four hours with additional doses every two hours as needed. If patients are already receiving opiates for pain management, these should be continued and increased as needed. A continuous infusion with boluses of morphine (1 mg-2 mg) every five to 10 minutes until dyspnea is relieved is often used. Respiratory depression is uncommon if morphine is titrated to patient response. Nebulized opiates are also a safe and effective alternative option, but may induce bronchospasm and should be given in a setting where this can be managed.
When dyspnea is associated with anxiety, benzodiazepines are an effective treatment option often used in combination with opioids. As with opioids, benzodiazepine medications should be started at a low dose and titrated up to desired effect. Lorazepam (Ativan), which has a short half-life, can be administered orally, sublingually and parentally. After a 2 mg to 4 mg bolus, a 1 mg to 5 mg per hour constant infusion may be given.
In addition to opioids and benzodiazepines, diuretics, bronchodilators, corticosteroids, antibiotics and anticholinergic agents may be effective in relieving dyspnea, especially in cases when an underlying cause has been identified. As with all treatments provided to a palliative patient, the benefit of dyspnea treatment should be weighed against any treatment burdens, patient wishes and prognosis.
Margaret M. Eberl, MD, MPH, is a Pain and Palliative Care Physician at Roswell Park Cancer Institute.
For more information:
- Waller A, Caroline NL. Handbook of Palliative Care in Cancer. Boston: Butterworth-Heinemann; 1996.
- Lipman AG, Jackson KC, Tyler LS, eds. Evidence Based Symptom Control in Palliative Care: Systematic reviews and validated clinical practice guidelines for 15 common problems in patients with life limiting disease. New York: The Haworth Press Inc.; 2000.
- National Comprehensive Cancer Network (NCCN). Clinical Practice Guidelines for Oncology: Palliative Care. Vol 2007. Fort Washington, PA: NCCN; 2007. Available at www.nccn.org.