RISK FACTORS AND PREVENTIVE INTERVENTIONS FOR PRESSURE INJURIES IN CANCER PATIENTS

Objective: identify and describe the risk factors for the development of pressure injuries in adult cancer patients and interdisciplinary preventive interventions. Method: integrative literature review. Data collection was carried out between March and April 2019 and December 2020, using the databases: BDENF; PubMed/ Medline; Embase; Scopus; Cinahal and Web of Science. Results: the sample consisted of 16 articles published from 2008 to 2019. Among the risk factors identified, the following stand out: nutritional status, advanced age, incontinence and immobility; the interdisciplinary preventive interventions identified were: decubitus change, nutritional assessment and monitoring, skin care and use of support surfaces. Conclusion: further studies are needed to take a careful and assertive look at cancer patients. de


INTRODUCTION
The cancer patient, due to the severity of his health condition, may experience limitations in his activities of daily living. Such changes can alter their sensory perception and cause impairment in mobility, predisposing the patient to the development of skin lesions, highlighting, among them, pressure injury (PI) 1 .
PI is defined as "localized damage to the underlying skin and or soft tissues, usually on a bony prominence or related to the use of a medical or other device". The lesion can appear on intact skin or as an open ulcer and can be painful, occurs as a result of intense and /or prolonged pressure in combination with shear, being classified according to severity in stages 1 to 4, unstageable PI and deep tissue PI. There are still two additional categories: PI related to medical device related pressure injury (MDRPI) and mucous membrane PI 2,3 .
It is known that PI is a major health problem in hospital environments and in communities, marked by high prevalence and incidence worldwide 1,4 . However, articles on PI in cancer patients are scarce.
Some factors related to cancer, especially when the disease is in an advanced stage, favor the appearance of PI 1,5 . Among these factors, there is a decrease in the ability to move around, loss of nutrients and proteins due to hypermetabolism and neoplastic cachexia. In addition, most of them are older patients, undergoing typical physiological changes, such as delayed granulation, the interconnection of collagen fibers and poor vascularization, thus decreasing skin resistance. These changes are even more pronounced in cancer patients, since the use of antineoplastic agents causes dermal, epidermal and collagen alterations 5 .
Notoriously, the fragility and the large number of risk factors associated with the populations of cancer patients in palliative care have the highest incidence of all types of wounds, among which PI predominates, comprising up to 60% 6 .
Other factors associated with the appearance of PI in cancer patients are related to defects in healing caused by chemotherapy, since this can promote the occurrence of spinal aplasia, anemia, agranulocytosis and low productivity of platelets, providing conditions for the emergence of infectious processes 5 .
Many patients use immunosuppressive drugs that negatively affect the healing process, in addition to favoring a reduction in the inflammatory response and the appearance of infections. Events such as skin lacerations, surgeries, skin involvement by radiation during radiotherapy sessions and extravasation of chemotherapy drugs out of the vein are also frequent in this public, causing tegumentary changes and inflammatory processes that, together with the evolution of the disease itself, also interfere in the healing of wounds, thus prolonging the discomfort and pain caused by skin lesions, including the PI 7 .
Covering interprofessional interventions for the prevention of PI, international guidelines 2 recommend a series of conducts for their prevention and assistance in the treatment, however these strategies must be adequate and adapted in their applicability with the cancer patient.
Due to its specificities, cancer patients can benefit from certain strategies, such as the use of enteral nutrition for nutritional rescue 6 .However, they may not benefit from strategies such as repositioning without specific criteria for each patient, as it can generate pain, use of opioids and, consequently, less mobility in the bed, in addition to impairing their comfort 8 .

Risk factors and preventive interventions for pressure injuries in cancer patients
The PI acquired in the hospital has received increasing attention from government, regulatory and quality agencies in the last decades, as it is an adverse event, most of the time, preventable, which has a negative and significant impact for the patient, for the team and for the health institution for adding costs generated with the treatment and increasing the hospitalization time 9,10 .
It is estimated that there is an enormous expense with the treatment of PI that, many times, could potentially be avoided with effective preventive interventions 2 . The PI may worsen the initial condition of the disease, complicate the prognosis and still cause death to the patient 5 .
Thinking about all the peculiar characteristics of the cancer patient, an assertive and specific look is needed to recognize the risk factors of this population, in order to implement preventive interventions.
Given the above, this study was proposed with the objective of identifying and describing the risk factors for PI in cancer patients and the interdisciplinary preventive actions that may contribute to the practice of integrated care and in an interprofessional way for this population.

METHODS
It is an integrative literature review that used the acronym PICo for the elaboration of the research question: P -population; I -Intervention; Co -Context 11 , in which P = adult cancer patients; I = preventive interventions and risk factors for PI; and Co = care of an interdisciplinary health team. The search terms were constructed using the PICo model, which for "non-clinical" research represents an acronym for Patient, Investigation and Context, and which aims to simplify the construction of the research question, in addition to facilitating the research process 11 .
Thus, to guide this integrative review, the following questions were asked: what are the risk factors for PI in adult cancer patients under the care of a health team? What are the interdisciplinary preventive interventions for PI in this population?
The study was carried out by searching for articles indexed in the databases of national and international literature: The inclusion criteria used were: articles related to the research question, published from January 2008 to December 2020, in English and Portuguese, and available in summary form and with full text (free/free access). Articles whose study population consisted of patients assisted at home by a caregiver and/or family member and other types of publications, such as theses, dissertations and letters to the editor, were excluded.
To search for the articles, the descriptors MesH -Medical Subject Headings were used: "Patient Care Team" In order to improve the results of the study and capture more articles, the Embase database was used with an entree 12 , in which the synonyms of the MeSH descriptors were added according to the following example: EMBASE=SourcesEmbase, MEDLINE Query('decubitus':ti OR 'decubitus':ab OR 'pressure ulcers':ti OR 'pressure ulcers':ab OR 'pressure injuries':ti OR 'pressure injuries':ab) AND ('neoplasm' OR neoplasm:ti OR neoplasms:ab OR cancer:ti OR cancer:ab) AND ('hospital patient' OR inpatient:ti OR inpatient:ab). Were retrieved 53 articles by reading the title, 46 after reading the title and abstract, and 43 were excluded after reading the full article.
The study selection process was carried out in relation to the total number of studies retrieved in the searches.
Two different researchers and individually analyzed the articles by title and abstract, identifying the articles relevant Lima AR, Palmer CR, Nogueira PC to the topic. By means of a consensus between the two researchers and according to the inclusion and exclusion criteria, the articles to be read in full were selected. The studies were submitted to the evaluation of their scientific quality through the classification of the levels of evidence (Table 1)  Strong evidence, such as a randomized controlled clinical trial that is considered the gold standard in Evidence-Based Practice, is still scarce in the literature. However, the absence of strong evidence does not preclude evidence-based decision-making; what is required is the best available evidence and not the best possible evidence 13 .
The data extraction was carried out by the researchers through the critical evaluation of the articles and filling out a form with the following data: (1) author/year of publication; (2) title of the article; (3) title of the journal; (4) professional category; (5) objective; (6) method (study design and location, sample)/level of evidence (according to Table 1); (7) risk factors for PI; (8) preventive interventions; (9) conclusions/recommendations.

RESULTS
The search strategy used allowed the retrieval of 158 articles, of which 46 duplicates were excluded and 112 publications were selected. After analyzing the title and abstract, 70 articles were excluded. Of the 42 selected for reading in full, 18 were excluded after reading and 8 articles whose content was not available for reading in full were also excluded, totaling 16 studies that made up the final sample.
Among the 16 papers included in this study, Pubmed was the database with the most publications, totaling 5 articles (32%), followed by Web of Science and Embase, with 3 each (19%), Cinahl and BDENF Enfermagem with 2 (12%), and finally, Scopus with 1 publication.
Below is the flowchart for identification, selection and inclusion of articles (Fig. 1).
The included studies were developed in 8 different countries, 7 (44%) in Brazil. There were also works carried out in the United States of America (19%), Portugal, Italy, Canada, France, Jordan and Australia (all of them with 1 study each).
Regarding the study site, 12 (75%) were performed in a hospital environment, 3 (21%) were performed in a Palliative Care Clinic environment and 1 (7%) in Home Care.

Risk factors and preventive interventions for pressure injuries in cancer patients
The studies had different characteristics in relation to the types of study, methodological design and levels of evidence, as shown in Table 2.    Tables 3 and 4, together with the frequency that each of these factors was considered in the studies.
Risk factors and preventive interventions for pressure injuries in cancer patients

DISCUSSION
From the results presented in this study, it was possible to observe that cancer patients can, due to several factors, be extremely vulnerable to the development of PI. In relation to the risk factors for PI, the international guidelines for prevention and treatment 2 highlight a series of events whose impacts must be considered, such as immobility, previous presence of lesions, perfusion and oxygenation of deficient skin, impaired nutritional status, advanced age, among others. All of these risk factors were present in cancer patients and were highlighted in the articles that comprised this integrative review.
The risk factor for PI most pointed out in the studies selected in this review was advanced age. This is because the incidence of cancer in the elderly is much higher, representing a considerable percentage of bedridden patients with cancer who are more susceptible to the development of PI 15 . In addition, in general, the elderly are at a higher risk of impaired skin integrity, since with advancing age there is a decrease in turgidity and skin elasticity. When affected by neoplasms, these patients may have an aggravated condition and the appearance of lesions favored, also, by the addition of changes in immunological mechanisms and tactile sensitivity that could function as intrinsic protective barriers 4 ,so that for this audience the correct diagnosis of the lesions, as well as the constant monitoring of both skin lesions and the general conditions of patients is essential for their prevention.
International guidelines 2 recommend using risk assessment scales at the time of admission and frequently during hospitalization. Studies have shown that the predictive validity of these scales can be superior to clinical judgment, one example being the Braden scale 19,28 . The correct risk assessment for PI with the use of validated scales, in addition to the skin assessment, enables a more assertive management, be it the prevention or treatment of PI. It is the role of all health professionals who deal with direct care with the patient to observe and evaluate the integrity of the skin in each intervention, thus ensuring interdisciplinary work and comprehensive care 29 .
Two other risk factors, which were the second most cited in the articles of this integrative review, were nutritional deficiency and immobility. The studies analyzed highlighted nutritional assessment as a routine on admission and its exquisite monitoring during hospitalization, essentially focusing on patients who are at higher risk for PI. In a study conducted in Brazil, with a sample of 473 patients in which cancer was the most prevalent diagnosis (23.5%), it was Risk factors and preventive interventions for pressure injuries in cancer patients evidenced that the nutritional aspect has been shown to be strongly related to the risk of developing PI due to its negative impact on wound healing 18 . In a second study carried out in Brazil, a cross-sectional multicenter study, it was pointed out that nutritional deficits, such as cachexia and anorexia, and the lack of control of electrolytes caused by chemotherapy and radiotherapy are directly related to the appearance of injuries and are the cause of morbidity and mortality among cancer patients 20 . In addition, on the "nutrition" subscale of the Braden scale, patients with neoplasia had a lower score (higher nutritional risk) 20 .
In another study also carried out in hospitals in Brazil, with a sample of 187 patients, in which 13.4% of them had a diagnosis of neoplasms, it was observed that in more than 60% of patients there was identification of inadequate nutrition. In this study, patients with neoplasms had a worse nutritional status, which can be explained by a catabolic state, anatomical alteration of an organ caused by the disease (eg esophageal cancer, difficulty in swallowing) or by the treatment itself (radiotherapy, chemotherapy) that can prevent proper nutrition 20 .
The PI and malnutrition are an extremely inconvenient combination for patients, especially those with advanced age and terminal illnesses, so it is essential as a preventive intervention for cancer patients that the nutritional risk assessment for the development of PI is made at the time of admission or at most, in the first week of hospitalization and after that as part of the routine 18 .
As for immobility, it is usually directly related to the progression of the disease. Cancer-related pain is often severe and requires the use of opioid analgesics, which can reduce patient mobility due to the effect of drowsiness 4 , early repositioning and mobilization is essential as a preventive measure, as well as the correct use of skin protectors and pressure reducing devices, such as heel elevation, use of support surfaces for positioning, among others 2 .
Six studies (38%) indicated that the patient's gender may be a risk factor for the development of PI, however 4 pointed to the male gender and 2 to the female gender. The gender of the patient, however, appeared to influence more or less in some studies due to the prevalence of cancer in these (prostate in men and breast in women), so that no correlation was found in this factor directly related to the onset of PI 14,15,17,20,24,25 .
Another risk factor identified as frequent for cancer patients was urinary and fecal incontinence. In a descriptive cross-sectional study carried out in Goiânia with 90 adult individuals with advanced cancer, it was identified that urinary and fecal incontinence was evidenced as an important risk factor due to the increase in moisture and local acidity of the skin 24 , so that local cleaning with products with slightly acidified pH and the decrease in humidity in these regions are important measures to prevent the development of PI in patients in these conditions. In a study in Brazil, with a sample of 187 hospitalized patients, it was shown that in relation to the Braden scale, the subscale humidity (44.4%) is one of the items presented by patients among the greatest risk factors for development of PI 20 .
Thus, preventive interventions to control humidity and incontinence are necessary.
There is also, in many cases of incontinence, a relationship between these conditions and inadequate nutrition, as pointed out in a study conducted with patients admitted to the adult intensive care center of an oncology hospital in Rio de Janeiro, in which 84% of cancer patients had the symptoms of the 2 factors together 27 .
Anemia or low hemoglobin, mentioned in 4 (25%) of the studies, was also an important attribute of increased probability for the development of PI, usually reported in the form of fatigue 4,21,23,26 .This can, in most cases, be attributed to chemotherapy, immunosuppression and circulating catabolic factors, and nutritional monitoring and monitoring of patients under this condition is essential as preventive measures.
Shear and tissue damage were also relevant factors present in 3 (19%) of the studies analyzed, being related to other risk factors, such as malnutrition, immobility and dryness of the skin, and cancer is often responsible for causing these conditions, through decrease in activity levels and loss of muscle mass, favoring the development of injuries, so that, with the frequency of these events, measures such as repositioning the patient, the use of reducing and protective devices should be recommended 2,30 .
Major oncological surgeries have also been identified as a risk factor for PI. Often, patients with the most different types of cancers are subjected to treatments that involve long-term surgeries, a fact of extreme importance for the study, since scientific evidence show that surgical patients, in general, are predisposed to the development of PI due to immobilization time, increased surgical time, type of surgery, anesthesia, surgical positions and positioning (extrinsic factors) 4 . Oncological patients still usually have intrinsic factors already mentioned in this discussion, such as advanced age and impaired nutritional status, combined with chronic diseases, such as diabetes mellitus, vasculopathies, neuropathies, hypertension and anemia, which further worsen the risks when undergoing long surgeries 22 . There are studies that propose the application of specific protocols for the prevention of PI in surgical patients 23 .
Another highlight in the articles identified are cancer patients in palliative care. The incidence and prevalence of skin lesions in individuals at the end of life due to several comorbidities besides cancer are poorly explored, but it is estimated that PI occurs in at least one third of patients undergoing palliative care. At the end of life, health professionals/interprofessional staff should assist the patient and family in deciding whether the goals of injury care should focus on healing or palliation. In end-of-life patients, dressings should be used for general comfort, to prevent skin exposure to wound exudate and to reduce the number of potentially painful dressing changes 16,21 .
In a study conducted in Italy, a review of 414 medical records of hospitalized cancer patients, the author points out that the repositioning of these patients may cause pain or be limited by other factors, which may conflict with palliative care priorities. This study also notes that the strategies commonly used for the prevention and treatment of PI in terminally ill patients can impair their comfort 16 . Repositioning should be used in daily clinical practice with cancer patients, considering individual assessment, based on their clinical condition and prognosis, and respecting their choices. Interventions such as the use of skin protectors, pressure-reducing mattresses and pillows, prophylactic foam and silicone dressings can be used to improve the primary goals of palliative care in cancer patients at risk for PI 16 .
It was found in the present study that only one study proposed early mobilization. Bed-rested individuals should move to a sitting position and walk as quickly as they can tolerate. Programming of walking can help to compensate for clinical deterioration, which is often visible in individuals undergoing prolonged bed rest periods 4 . Noting that the patient's low mobility is related to the presence of PI and lower quality of life, it is necessary to stimulate the patient's functionality.
Another pointed risk factor observed in a systematic review conducted with 10 studies and 108 patients was that the pain caused by PI interferes with movement, functionality and participation in activities. It was also noticed that experiencing pain can compromise functionality, as it restricts mobility 31 . Thus, pain management is something that should be considered when instituting PI prevention protocols.
Other studies analyzed in this work have proposed different preventive interventions, such as educational actions with patients, family members and health professionals 24,25,29 .
There are controversies as to whether PI occur due to neglect of the care provided or whether they are unavoidable and are part of the natural history of advanced disease. Although there are controversies, there is a growing consensus that they are, in most cases, predictors of imminent death and not a direct cause of death 32 .
In view of the results found in the present integrative review, it is observed that cancer patients present several risk factors for PI, requiring the recognition of these risks by the entire health team so that preventive interventions can be implemented, respecting the specificities and characteristics of this population, as well as their comfort.
It is noteworthy here that the main limitation for carrying out this research was the lack of articles that correlate risk factors for the development of PI, as well as measures for prevention with the intrinsic aspects presented by cancer patients.

CONCLUSION
According to the results presented in this review, the risk factors for the development of PI in cancer patients, in general, were the same factors highlighted in the international guidelines for the prevention and treatment of PI.
The advanced age factor was the most risk factor cited in the studies, but it is more related to the frequency with which oncological diseases are present in these patients.

Risk factors and preventive interventions for pressure injuries in cancer patients
Nutritional deficiency is a factor of known importance for the development of PI and is directly related to the intrinsic aspects involving cancer patients, so that the correct nutritional assessment together with the continuous monitoring of this variable, becomes essential for the prevention of injuries. in these patients.
Tissue damage resulting from treatments such as chemotherapy and immunosuppression, as well as urinary and fecal incontinence are risk factors for PI, very common in cancer patients, so that the correct assessment of the skin and lesions, in the first case, and the cleaning of the skin with slightly acidified pH products and local humidity control are essential to prevent them.
Cancer patients undergoing surgery, prolonged hospitalizations and under palliative care are more exposed to the risk factors that cause these injuries and need a broad and specific look from the interdisciplinary team.
More traditional measures for the prevention of PI, such as repositioning and pressure-reducing support surfaces are the most used measures for cancer patients, so they continue to be recommended through analysis of each case.

DATA STATEMENT AVAILABILITY
Not applicable FUNDING Not applicable