Abstract
Pain is a serious problem for people with life-threatening illnesses. Accurate diagnosis and management require awareness of painful syndromes seen in cancer and other illnesses. Cancer pain syndromes can arise from the disease or from treatment, such as surgery, radiotherapy, chemotherapy, immunotherapy, and other treatments. Chronic pain syndromes associated with other noncancer illness have been poorly characterized but are widespread. Pain, dyspnea, anxiety, depression, and other symptoms are common in advanced disease and as a result, assessment should incorporate tools that evaluate these and other symptoms. Several tools, including the Edmonton Symptom Assessment Scale, the M.D. Anderson Symptom Inventory, and the Memorial Symptom Assessment Scale, are valid, reliable, and feasible in this population. Assessment may be challenged in more advanced illness when patients are unable to verbalize. In those settings, clinicians rely on behavioral cues such as the furrowed brow. During end of life, alternate routes of administration may be necessary and doses may be reduced due to organ system dysfunction. Systems of care, such as palliative care and hospice, focus on control of symptoms and providing care that is concordant with the patient’s preferences. In both of these types of health care delivery, care addresses biopsychosocial and spiritual concerns, and the unit of care is the patient and their family. All health care professionals are responsible for care of the dying. Comprehensive assessment and management of pain and symptoms at the end of life provide relief and more positive memories for loved ones at the bedside of these individuals.
Keywords
dyspnea, end of life, hospice, opioids, pain, palliative care, routes
Pain is a serious problem for people with life-threatening illnesses. In studies exploring symptoms experienced near the end of life, pain, dyspnea, anxiety, and depression are common. Cancer pain has been well characterized, representing a wide array of syndromes. These range from acute episodes related to procedures, such as bone marrow aspiration, to chronic syndromes emanating from direct tumor involvement or cancer therapies. Although it may be common during advanced disease, cancer pain can be relieved in 80% to 90% of patients. Less is known about pain occurring in persons with other life threatening illnesses ordinarily seen in palliative care or hospice, such as congestive heart failure, end-stage renal disease, or neuromuscular disorders. An awareness of the most common syndromes in these populations, specific assessment techniques, as well as therapies used to treat these conditions is essential to providing relief.
Until recently, experimental models that elucidated the neurobiology of pain due to cancer or other life-threatening illnesses did not exist, limiting our understanding of the unique mechanisms of these phenomena. The development of rodent models of bone pain, chemotherapy-induced peripheral neuropathies, and other syndromes provides insights into the neurobiology of cancer pain. These discoveries are leading to the new, targeted, mechanism-based therapies. Furthermore, greater understanding of cancer pain biology may enhance knowledge related to other symptoms common in end of life care. For example, initial evidence surrounding the role of inflammatory cytokines suggests a common biological mechanism between pain, fatigue, depression, and other symptoms. These investigations are critical to complete our understanding of symptom management for those in palliative care or hospice.
Palliative Care and Hospice
All health care professionals, regardless of their specialty area, are responsible for care of the dying; therefore, they must gain the necessary knowledge and skills to care appropriately for those patients. Pain and symptom management, along with advance care planning, are key elements of primary palliative care. Resources, such as palliative care services and hospices, are available to assist clinicians as these teams provide specialized care to patients with life-limiting diagnoses and their families.
Palliative care is the “active total care of patients whose disease is not responsive to curative treatment. Control of pain, of other symptoms, and of psychological, social, and spiritual problems is paramount. Palliative care affirms life and regards dying as a normal process.” Palliative care is best integrated into the patient’s care early in the course of the disease, rather than being segregated to the last days or weeks of a person’s life. Palliative care is often provided through consultation services, inpatient units, outpatient clinics, home care, day programs, and other creative models. Studies reveal that palliative care can lead to improved quality of life, enhanced mood, longer survival, and cost savings when compared with those individuals receiving standard care. Palliative care services are expanding rapidly in the United States, with almost universal access in large hospitals and academic medical centers.
Hospice care in the United States is a philosophy of care with similar tenets to palliative care. Goals include attention to alleviation of physical and emotional suffering, along with focus on the patient and family as the unit of care. Most hospice care in the United States is provided within the home, although a few free-standing units exist for patients unable to be cared for in the home. Hospice is reimbursed through the Medicare hospice benefit. Qualified patients must be certified as having a life expectancy of 6 months if the disease takes its natural course. Recent studies reported that families of patients dying of cancer were more satisfied with end-of-life care when treatment is focused on comfort in a hospice rather than aggressive treatment in a hospital’s intensive care unit.
Painful Syndromes in Cancer and Other Life-Threatening Illnesses
Awareness of the painful syndromes seen in those with cancer and other life-threatening illnesses promotes accurate diagnosis and management. Other chapters in this book describe a variety of pain syndromes that, although primarily seen in the general population, also may occur in people with life-threatening illnesses. However, several syndromes occur uniquely in those with cancer or other advanced diseases.
Cancer
Cancer pain syndromes can be grouped in a variety of categories: acute versus chronic, somatic versus neuropathic, and disease versus treatment related. Acute pain is generally due to invasive procedures, such as diagnostic or surgical interventions, and is not unlike the experience of patients with nonmalignant disease. Examples of treatment-related acute pain unique to individuals with cancer are noted in Table 35.1 . Chronic pain syndromes often include involvement of bone, soft tissue, the viscera, and the nervous system. Bone metastases are common sources of pain, particularly in patients with breast, lung, or prostate cancers. Lymphedema, occurring in approximately 20% of women who undergo axillary node dissection, is an example of soft tissue pain associated with significant physical and psychological morbidity. Visceral pain may arise from involvement of tumor within the liver, intestine, kidney, peritoneum, bladder, or other organs. In addition, neuropathic pains can evolve from numerous causes, may be difficult for patients to describe, and are often complex to treat ( Table 35.2 ). Finally, many people with cancer experience syndromes unrelated to the cancer or its treatment, such as osteoarthritis.
| Chemotherapy |
|---|
| Arthralgia and myalgia induced by paclitaxel |
| Cold allodynia induced by oxaliplatin |
| Headache due to methotrexate or l -asparaginase |
| Mucositis commonly due to pretransplant chemotherapy regimen |
| Pain due to infusion of chemotherapy into peritoneum or bladder |
| Growth Factors |
| Myalgia, bone pain, fever, headache |
| Hormonal therapy |
| Flare syndrome (myalgia, arthralgia, and headache) in prostate or breast cancer |
| Immunotherapy |
| Myalgia, arthralgia, and headache due to interferon |
| Radiation |
| Bone pain flare (due to radionuclides) |
| Enteritis and proctitis |
| Mucositis |
| Myelitis when spinal cord is irradiated |
| Cancer-Related |
|---|
|
| Noncancer Causes of Neuropathies |
|
Other Life-Threatening Illnesses
The prevalence and types of pain experienced by patients with specific nonmalignant diseases at the end of life have not been fully characterized. Examples include neuropathic pain associated with multiple sclerosis, chest pain due to end-stage cardiac disease, and pain due to pressure ulcers or immobility in those who are debilitated ( Table 35.3 ).
| Disorder | Pain Syndromes |
|---|---|
| Cardiovascular disease Cardiomyopathy Congestive heart disease Peripheral vascular disease | Chest pain Ischemia |
| Cirrhosis | Abdominal pain due to portal hypertension, esophageal varices |
| Debility | Myalgias due to immobility Painful pressure ulcers Abdominal pain due to constipation, impaction Suprapubic pain due to distended bladder |
| End-stage renal disease | Painful pruritus |
| HIV | Abdominal pain due to infectious gastrointestinal disorders Chest pain from pneumocystis pneumonia Headaches Herpetic neuropathy Myalgia Neuropathies due to antiretrovirals and the virus |
| Neuromuscular disorders ALS Multiple sclerosis (MS) Spinal cord injury | Painful spasticity Lower extremity dysesthesias Periorbital pain and trigeminal neuralgia (MS) |
| Pulmonary disease Embolism Infection Pneumothorax | Chest pain Dyspnea |
Assessment of Pain at the End of Life
The assessment techniques described in other chapters should be applied to patients with cancer or other life-threatening illnesses. Intensity, location (or often, multiple locations), quality, temporal nature of the pain, and factors that alter the pain are critical to ascertain. As with all other pain syndromes, a thorough history is followed by a comprehensive physical examination, with particular emphasis on the neurologic evaluation. Radiographic, laboratory, and other diagnostic techniques may be indicated, although in caring for those at the end of life, treatment decisions may be made empirically to avoid uncomfortable scans or invasive procedures.
When patients are unable to verbalize or describe their pain, clinicians can use the furrowed brow as a proxy measure of pain. If there is no response to adequate doses of opioids or other analgesics, additional sources of distress (e.g., distended bladder or fecal impaction) should be explored.
While the general assessment of pain is universal, several additional dimensions are critical at end of life. A psychosocial assessment is indicated and directed towards the meaning of the pain as well as the effect of pain on the patient and their caregiver. The findings of this assessment may suggest the need for education, to mediate fears of addiction, for example. The results of this questioning may also prompt referral to social workers, chaplains, or others who are trained to address the existential distress or suffering experienced by the patient or their family.
Pain does not exist in isolation and symptom clusters are common, particularly at end of life. Several instruments have been designed to measure clinically multiple symptoms, including the Edmonton Symptom Assessment Scale (ESAS), the M.D. Anderson Symptom Inventory (MDASI), and the Memorial Symptom Assessment Scale (MSAS) Another tool, the Distress “Thermometer,” is a vertical visual analog scale designed to look like a thermometer, with 0 meaning “no distress” and 10 (at the top of the thermometer) indicating “extreme distress.” Accompanying the distress scale is a checklist of various physical, psychological, practical, family support, and spiritual/religious concerns. These are brief, clinically useful tools that quantify the intensity of a variety of symptoms common at end of life ( Table 35.4 ). The specific needs of people enrolled in hospice are addressed in the Brief Hospice Inventory (BHI). The BHI assesses outcomes of hospice patients, including physical and psychological symptoms, patient’s perceptions of hospice care, as well as ratings of their quality of life. Each statement is measured using an 11-point scale.
