Issue: Volume 55 - Issue 2 - February, 2009
Abstract
Pain is an ever-present problem in patients with pressure ulcers. As an advocate for persons with pressure ulcers, the National Pressure Ulcer Advisory Panel (NPUAP) is concerned about pain. To synthesize available pressure ulcer pain literature, a systematic review was performed of English language literature, specific to human research, 1992 to April 2008, using PubMed and the Cumulative Index in Nursing and Allied Health Literature.
Fifteen relevant papers were found; they examined pain assessment tools, topical analgesia for pain management, and/or descriptions of persons with pressure ulcer pain. Studies had small sample sizes and included only adults. The literature established that 1) pressure ulcers cause pain; 2) pain assessment was typically found to be self-reported using different versions of the McGill Pain Questionnaire, Faces Rating Scale, or Visual Analog Scale; 3) pain assessment instruments should be appropriate to patient cognitive level and medical challenges; 4) in some cases, topical medications can ease pain and although information on systemic medication is limited, pain medications have been found to negatively affect appetite; and 5) wound treatment is painful, particularly dressing changes. Research gaps include the prevention and treatment of pressure ulcer pain, the impact of pain on nutrition, and pressure ulcer pain considerations for special groups (eg, children, end-of-life patients, and bariatric patients). The NPUAP presents this white paper as the current scientific know-ledge base on the topic. Research regarding the multidimensional aspects of pressure ulcer pain is strongly recommended.
Pain is an ever-present problem in patients with pressure ulcers.1 As a protective physiologic mechanism, pain is defined as an unpleasant sensory and emotional experience associated with actual or potential tissue damage.2 Irrespective of a patient’s age or health status, pressure ulcer pain needs to be assessed and treated because it has widespread physical and psychosocial implications for the patient, family, and clinician. Zanca et al3 identified 32 grants as part of their examination of pressure ulcer research funding; topics included pressure ulcer assessment, prevention, and treatment; quality of care studies that include pressure ulcers in their outcomes; or foot pressure management in patients with diabetes mellitus. Only one focused on pain. Although pressure ulcer pain is underrepresented among the funded projects, practitioners are asked to base pain assessment and treatment on research evidence. This paper summarizes research findings specific to pressure ulcer pain in terms of pain assessment tools, medications, wound care, and nutrition.
Pathophysiology of Pressure Ulcer Pain
Pressure ulcer pain may be caused by tissue trauma from sustained loads, inflammation, damaged nerve endings, infection, dressing changes, debridement, operative procedures, and other treatments. The skin has more sensory nerves than any other body organ. 4 As the pressure ulcer cellular damage expands, chemicals are released that irritate nociceptive nerve terminals. Nociceptive pain is an appropriate physiological response to a painful stimulus and involves acute or chronic inflammation. 5,6The ulcer erodes through tissue planes and destroys nerve terminals. As peripheral nerves regenerate, the nociceptive nerve terminals send out immature sprouts of nerve tissue that may be hypersensitive to both noxious and non-noxious stimuli. A heightened sensitivity to pain in the wound is primary hyperalgesia; a heightened sensitivity to pain in the surrounding skin is secondary hyperalgesia.5,6 Infection further irritates free nerve endings and may cause pain. 7 Pain, particularly acute pain, is also a stimulus to the stress response; thus, at the cellular level, hypoxia may develop because of limited painful breathing and peripheral vasoconstriction and impede wound healing.8 Pain also may diminish appetite and decrease nutritional status.
Pain threshold and perception. Besides the physical causes and impact of pressure ulcer pain, pain threshold and perception are important considerations. Pain threshold is the amount or degree of a noxious stimulus that leads a person to first interpret a sensation as painful. Pain perception is the actual awareness of the painful feeling or sensation; it may be acute or chronic. Pressure ulcer pain perception can be intensified by psychosocial factors, grief about the ulcer’s cause and presence, and anger and fear in knowing its long-term treatment impact.
To enhance understanding and ultimately treatment of pressure ulcer pain, this paper synthesizes the available relevant pressure ulcer pain literature. The National Pressure Ulcer Advisory Panel (NPUAP) presents this white paper as the current scientific knowledge base on the topic.
Methodology
Literature searches were performed using PubMed, a service of the National Library of Medicine and the National Institutes of Health, and the Cumulative Index in Nursing and Allied Health Literature (CINAHL®) for the years 1992 to 2008. Words/phrases used for the search included pressure ulcer pain, bedsore pain, and decubitus ulcer pain. The search was limited to English language and human research. Fifteen papers were identified — four addressed topical medication treatment and 11 presented varied aspects of pain measurement, pain treatment, and pain experiences. Papers about other types of wound pain and quality of life where pain was one of many variables examined versus the critical variable were not included in this review.
deLaat et al9 completed the last published systematic review about pressure ulcer pain describing scientific evidence and making recommendations for practice; their review also included malodor and exudate. Six papers in deLaat’s review are included in the current review. Table 1 summarizes the pressure ulcer pain research obtained from this search in terms of author/year, type of study, participants/sample, purpose, protocol, and findings/main outcomes.
Results
Pain assessment scales used in pressure ulcer pain research. The single most reliable indicator of the existence and intensity of pain and any resultant distress is the patient’s self-report through the use of established reporting instruments. Three pain rating scales were used in pressure ulcer pain research: the McGill Pain Questionnaire (MPQ), the Faces Rating Scale (FRS), and the Visual Analog Scale (VAS).
Szor and Bourguignon10 used the MPQ because its description of pain qualities and measure of pain intensity provided a quantitative measure of pain. The MPQ contains the Pain Rating Index scale score and Present Pain Intensity scale score. The most frequently used descriptors by pressure ulcer stage were: tender, hurting, sore (Stage II); burning, tender, hurting, sharp, sore, wretched (Stage III); and tender, hurting, smarting, penetrating, and throbbing (Stage IV). Although persons with Stage IV pressure ulcers had higher Pain Rating Index and Present Pain Intensity scores, they did not differ significantly from ratings by persons with Stage II or Stage III pressure ulcers. Roth et al11 used the MPQ and a singular pain intensity rating. No differences were found in pain ratings for Stage III and Stage IV pressure ulcers. Persons with either Stage III or Stage IV pressure ulcers had significantly (P <0.05) more severe pain (ie, MPQ total and sensory and affective subscales) than persons with other wounds.
In Brazil, Quirino et al12 used a short version of the MPQ. Key descriptors used by persons with Stages I and Stage II pressure ulcers included throbbing, sharp, burning, aching, and tugging. No study provided reliability or validity data about use of the MPQ for pressure ulcer pain.
Dallam et al13 used the FRS and the VAS. They found the VAS correlated with the FRS (r = .92) and the VAS correlated with pressure ulcer stage (r = .37). The intensity of pressure ulcer pain correlated with generalized pain (r = .59). Using data from the Dallam study, 13 Freeman et al14 reported statistical properties of the VAS and FRS for pressure ulcer pain. VAS variability significantly increased (P <0.01) with increasing FRS values. VAS and FRS were highly reliable for pain assessment in persons with diminished verbal and abstract thinking abilities and participants did not find them difficult to use. Freeman et al14 presented a mathematical translation of the FRS findings into VAS units. The VAS has since been used in studies about pressure ulcer pain and medication use (information to follow). 15,16
Gunes17 used the MPQ and the Faces Rating Scale-Revised (FRS-R) in a study involving 47 persons with Stage II to Stage IV pressure ulcers. He reported a statistically significant relationship between the patient’s present pain intensity and the FRS-R (r = .90); FRS-R mean pain intensity scores were rated as moderate pain. He also found that MPQ completion time was challenging for some participants and that pain intensity increased with pressure ulcer stage. Only six patients received pain medication within 6 hours before completion of the questionnaire and none of the medications was prescribed specifically for pressure ulcer pain.
Qualitative pressure ulcer pain studies1,18-20 were not found to use a specific pain scale — rather, participants were asked to respond to open-ended questions about pain. Langemo et al’s study1 included eight participants who described their pressure ulcer experience; pain emerged as a theme. Fox18 used a semi-structured interview in which five patients shared individual experiences of living with a pressure ulcer. Pain was the dominant, recurring physical factor theme — an overwhelming aspect of living with a pressure ulcer. Hopkins et al19 used unstructured interviews with eight persons to probe for themes of living with a pressure ulcer; endless pain was one of three themes. In Rastinehad’s study,20 10 patients described what it was like to have a painful pressure ulcer. Although sample sizes were generally small in qualitative studies, pain was a critical theme.
Because pressure ulcer pain research is limited, it is important to consider evaluating pressure ulcer pain assessment options for special populations of patients. Patients with cognitive impairment have been found to respond to pain assessment tools such as the Faces Pain Scale and the Present Pain Intensity subscale of the MPQ.21,22 Simple yes/no questions (eg, Are you uncomfortable? Do you feel pain?) are used to assess pain. Family members or caregivers can report expressions/behaviors they recognize as indicators of pain. For critically ill intensive care patients, the Behavioral Pain Scale (BPS) assesses pain in terms of facial expression, upper-limb movement, and ventilator compliance.23
Pressure ulcers in children need to be considered a source of pain.24 Pain assessment scales used with this population include the 0 to 10 pain rating scale or the FACES. 25 The Face, Legs, Activity, Cry, Consolability (FLACC) scale26 is a behavioral pain assessment instrument initially developed for scoring postoperative pain in young children. The FLACC has been found to have high (r = .94) reported inter-rater reliability.27 The revised FLACC scale that includes specific descriptors and identifies unique behaviors for individual children has been found to have intra-class correlation coefficients ranging from 0.76 to 0.90.28 Construct validity was demonstrated by decreasing FLACC scores following analgesic administration. 28 For assessment of pain in neonates (ages 0 to 6 months), the Crying; Requires O2 for Saturation >95%; Increasing vital signs; Expression; Sleepless (CRIES) scale has been used effectively and has a high reported reliability.29,30
Medications for pressure ulcer pain treatment. Researchers have examined the use of topical medications for pressure ulcer pain treatment.15,16,31,32 Zeppetella’s,15 Prentice et al’s,16 and Flock’s32 studies used a randomized double-blind placebo controlled design; in addition, Zeppetella’s15 and Flock’s32 studies included a crossover component. Jepson’s31 descriptive study (N = 17) was presented as a letter to the editor.
Zeppetella et al15 used the VAS to examine the analgesic effect of 10 mg of morphine sulfate injection in 8 g Intrasite gel (Smith & Nephew) applied topically to painful pressure ulcers compared to water for injection 1 mL in 8 g Intrasite gel for five patients.15 Participants continued with their regularly scheduled analgesia. They had lower (P <0.01) VAS scores with the morphine gel treatment (gel alone mean + standard deviation = 47 + 11 versus morphine gel = 15 + 11). Three patients reported localized discomfort with the gel alone but not with the morphine gel. Systemic adverse effects were not noted with the morphine gel.
Flock32 examined the effectiveness of diamorphine gel to control pressure ulcer pain for 13 patients with grade 2 or grade 3 pressure ulcers. Pain scores were rated as none (score 0) to overwhelming (score 4). Among the seven patients who completed the study, pain score significantly improved 1 and 12 hours after the diamorphine gel was applied; this was not true for the gel alone. New symptoms that patients developed during the study (ie, skin irritation, pruritus, nausea/vomiting) were similar for the two treatments. One patient developed symptoms similar to opioid toxicity when her fentanyl patch was increased; her symptoms resolved when the fentanyl dose decreased.
Jepson31 reported that a aqueous-based cream containing 3% benzydamine was effective within 24 hours in reducing pressure ulcer pain. The pain scale used in the study was not named. In a study with more controls, Prentice et al16 used the VAS and an 11-point numerical pain score to examine the effect of topical benzydamine hydrochloride 3% cream as compared to a topical placebo cream on relief of pressure ulcer pain (N = 30). VAS and numerical pain scores decreased in both groups. The reduction in pain was greater in the benzydamine group but not significantly different. Comparing the VAS and numerical pain scale scores over time, Prentice16 noted the R-square values increased (ie, 66.4%, 74.2%, and 94.5%), indicating participants learned how to use the various scoring methods across the study.
The pressure ulcer pain literature included limited descriptive information about the use of systemic analgesics for this pain. Dallam et al13 reported three out of 132 participants (2.3%) were given pain medication for pressure ulcer pain within 4 hours of pain measurement. Drugs used by these patients that may have decreased pressure ulcer and other pain included narcotics, nonsteroidal anti-inflammatory drugs (NSAIDs), tranquilizers, psychotropics, and sedatives. Szor and Bourguignon10 reported seven persons (21.8%) received pain medication within 6 hours before completing the pain study; the medication was prescribed specifically for pressure ulcer pain for only two of these persons. None of the seven participants reported an absence of pain from the medication.
Studies on the use of systemic and/or local analgesics for pressure ulcer pain management in vulnerable patient groups (ie, neonates and children, patients with a history of substance abuse, morbidly obese/bariatric, minority groups, and at end of life) could not be found. This is an important concern. Children as young as 3 years of age have been found to have painful memories of procedures.33 Minority groups have been found to be at risk for inadequate pain control.34 Persons who have chronically used opioids have been found to have a decreased tolerance for pain.35 In addition, clinicians may have misconceptions and value judgments about pain treatment in persons who used illicit drugs, especially when the drugs were injected.36
Obese children and adults experience analgesic medication administration issues because excess body fat can alter drug absorption37 — for example, drugs that are highly soluble in fat (eg, diazepam and carbamazepine) need the dose calculated using the patient’s actual body weight, but drugs absorbed mainly in lean tissue (eg, acetaminophen) should have the dose calculated using the patient’s ideal body weight.37 If an obese patient is to receive pain medication by intramuscular injection, standard intramuscular needle length may not be sufficient to penetrate past the adipose tissue. Although the intravenous route is an option for more consistent administration of pain medication, vein access can be problematic in patients who are obese, as well as in persons who inject illicit drugs.
Langemo38 noted pressure ulcers are a concern for patients receiving palliative care but that little is known about wounds in these patients.38 For patients at the end of life, regular assessment for pain and use of therapies proven effective to manage pain are recommended.39,40
Although research was not found about the impact of systemic analgesics on pressure ulcer pain, systemic analgesics are a critical component in overall pain management and thus need to be considered for chronic pressure ulcer pain. The World Health Organization’s (WHO) Analgesic Dosing Ladder41 frequently is used as a guide for systemic pain medication management. The WHO ladder includes many categories of systemic medications for pain management (eg, NSAIDS, opioids, and adjuvants) and encourages matching the analgesic to the patient’s level of pain. Using a 10-point scale where 10 is the highest pain level, recommendations for analgesia include mild opioids for scores 1 to 3, moderate opioids for scores 4 to 6, and strong opioids for scores 7 to 10.42 Spontaneous or induced wound pain usually is treated with a supplemental systemic, rapid-acting opioid.43Breakthrough pain medications should be administered with sufficient time to take effect, such as before a painful pressure ulcer treatment. A pain management specialist may help determine the most appropriate medication protocols to minimize medication side effects and toxicity maximize pain reduction/relief.
Wound care and pressure ulcer pain. Pressure ulcer pain associated with treatment and/or wound care was reported in some studies. Dallam et al13 noted patients whose ulcers were treated with hydrocolloid dressings as opposed to management with other topical dressings (P <0.02) had significantly less pain. Szor and Bourguignon10 reported 87.5% of participants had pain at dressing change. This pain ranged from mild (n = 21) to excruciating (n = 5). Pain did not differ at rest and at dressing change across the stages of ulcers. Spilsbury et al44 reported that eight out of 23 persons (34.8%) had pain with dressing change. Gunes17 reported that 32 out of 47 patients (68.1%) stated dressing change aggravated pressure ulcer pain.
Although procedural pain may be addressed in literature regarding specific treatments, information on pressure ulcer pain research conducted during procedures/treatments was not found. Some authors presented findings about wound dressings and pain in general. For example, the Thunder Project II45 (N = 6,201) described pain related to procedures commonly performed in critical care settings; one of the painful procedures was wound dressing change. Adolescents gave wound care the highest pain intensity score and adults rated it the third most painful procedure (following turning and wound drain removal).
Choosing dressings that may mitigate the pain associated with dressing changes and administering an analgesic before dressing changes have been found to be possible strategies for pain management. 46 Pain rated as moderate (eg, 4 on a 1 to 10 scale) should prompt breaks during the dressing change, improved analgesia, and a review of current dressing protocols.6 The World Union of Wound Healing Societies,6 using a modified Delphi approach, developed a document that lists principles of best practice for minimizing pain at wound dressing-related procedures. These principles include: 1) be aware of current wound pain, 2) avoid unnecessary manipulation of the wound, 3) explore patient-controlled techniques to minimize wound pain, 4) assess the skin and surrounding tissue for infection, necrosis, and the like, 5) consider the temperature of the wound products, 6) avoid excessive pressure to the wound from dressing materials, and 7) provide ongoing evaluation and manipulation of the management plan.
Nutrition and pressure ulcer pain. Specific research related to the impact of pressure ulcer pain on nutrition could not be found. However, Bosley et al47 reported chronic pain was associated with self-reported appetite impairment in older adults. The authors identified the need for research on the effect of pain reduction on appetite. Herr et al’s48 guideline about acute pain management in older adults includes a section about monitoring for nausea that may negatively impact nutrition. Guidelines49,50 on palliative care recommend minimizing dietary restrictions, offering small quantities of food at a time, and offering food more frequently throughout the day. Patients should select foods that match their appetite in terms of appearance, consistency, and aroma. The decision to use medications to stimulate appetite should be made on an individual basis. Pain medication in and of itself may affect appetite and taste.
Conclusion
The NPUAP is an advocacy organization that believes that all, or nearly all, pressure ulcers cause pain. The NPUAP also believes it is crucial to increase the scientific knowledge base for pressure ulcer pain and disseminate this knowledge, particularly to the bedside clinician. Healthcare providers report that dressing change and wound treatment are among the most painful times for an individual with a pressure ulcer.
Pain assessment scales are available and have been used in research to measure pressure ulcer pain. Open-ended questions about pain also have identified the presence of pain in persons with pressure ulcers. Clinicians should have a high index of suspicion of pressure ulcer pain in patients including those who cannot respond (eg, patients with dementia, ischemia, and cancer). Irrespective of the pain assessment format used, patients with pressure ulcers need to be asked about their pain, using a structured tool or open-ended questions for assessment. Although pressure ulcer pain research has included Stage I through Stage IV to some degree, information on Stage I and Stage IV is more limited in published studies.
In general, research regarding pressure ulcer pain is limited. However, the results of this review underscore a number of perspicuous points. First, pressure ulcers cause pain. Pressure ulcer pain was identified in both quantitative and qualitative studies. Second, pain levels in individuals with pressure ulcers — including neonates, children, adults, and the elderly — must be routinely assessed. Third, a number of pain assessment tools have been used in pressure ulcer pain research and include the MPQ, FRS, and VAS. Pressure ulcer pain assessment tools should match the cognitive level of the patient and be appropriate for special groups, such as persons with compromised mental competence, substance abuse, bariatric concerns, spinal cord injury, and other neurological illness or end-of-life issues that can impair perception and pain reporting. Fourth, some research has noted the positive effects of topical medications for pressure ulcer pain. Research about the impact of systemic medications was not available. Fifth, wound care treatments such as dressing changes can cause pain. Given that dressings and their need for changing may cause pain, it is important to consider dressings based on their comfort and frequency of change. Lastly, pain medication can affect appetite and taste. The effect of pressure ulcer pain on nutritional status must be assessed. Pain medications should be administered on a schedule that maximizes the patient’s ability to eat and to be comfortable during pressure ulcer treatment. The goal is to optimize food/fluid intake and decrease the risk of nutritional problems such as weight loss and delayed healing.
Inadequate knowledge of pain is a barrier to its management. Although this review did not examine literature about pressure ulcer pain education, pressure ulcer education needs to include content regarding pain assessment and management. This education should focus on the patient, family, caregivers, and clinicians. Krasner51 noted clinicians need to become more sensitive to pressure ulcer pain and respond to it. Continued pressure ulcer pain research is needed to identify the most effective methods of assessing and managing pressure ulcer pain across the age continuum and for special populations.
The NPUAP, in collaboration with the European Pressure Ulcer Advisory Panel, is developing pressure ulcer prevention and treatment guidelines with international application. These guidelines will be released at the NPUAP Biannual Conference in Arlington, Virginia, February 27 – 28, 2009. Specific recommendations will be made for management of pressure ulcer pain.
Further research is needed about pressure ulcer pain, including the degree and type of pain for each pressure ulcer stage. Research questions might include: Are certain topical analgesics more effective for pain in different stages of pressure ulcers or on pressure ulcers in different body locations? Are certain systemic analgesics more effective for pain in different stages of pressure ulcers? Are certain analgesics more effective for acute pressure ulcer pain? What analgesic issues are relevant to chronic pressure ulcer pain? Are certain analgesics, whether topical or systemic, more effective for different aged individuals with a pressure ulcer? What are analgesic concerns and effectiveness issues for individuals with a history of substance abuse or for individuals at the end of life? What is the most effective timing schedule of analgesic medications in relation to effective nutrition and fluid intake? How can pain scale ratings be used to guide medication or dressing selection for a person with a pressure ulcer? What is the best method to assess the presence of pressure ulcer pain and to assess if pressure ulcer pain is relieved in the non-cognitively intact individual or in children? Research also might consider pain management strategies including, but not limited to, medications and nonpharmacologic strategies such as physical and occupational therapy, counseling, music, massage, and relaxation. The responses to these questions and concerns will help guide and improve care for patients with pressure ulcer pain.
Acknowledgment
The author thanks members of the National Pressure Ulcer Advisory Panel (NPUAP) Board of Directors 2007–2008 who provided critique of the manuscript. Dr. Pieper is a Professor/Nurse Practitioner, College of Nursing, Wayne State University, Detroit, MI. Dr. Langemo is a Distinguished Professor Emeritus and Adjunct Professor College of Nursing, University of North Dakota, Grand Forks, ND. Dr. Cuddigan is Associate Professor, Chair, Adult Health and Illness Department, College of Nursing, University of Nebraska Medical Center, Omaha, NE. Please address correspondence to: Barbara Pieper, PhD, ACNS-BC, CWOCN, FAAN, College of Nursing, Wayne State University, 5557 Cass Avenue, Detroit, MI 48202: email: 该Email地址已收到反垃圾邮件插件保护。要显示它您需要在浏览器中启用JavaScript。.
