Pain in emergency units: correlation with risk classification categories*

ABSTRACT Objectives: to correlate risk classification categories with the level of pain of patients in an emergency service. Method: cross-sectional study carried out in the Risk Classification of 611 patients. The variables studied were: age, gender, comorbidities, complaint duration, medical specialty, signs and symptoms, outcome, color attributed in the risk classification of and degree of pain. We used Analysis of Variance, a Chi-Square test and a Likelihood Ratio test. Results: the average age was 42.1 years (17.8); 59.9% were women; the green (58.9%) and yellow (22.7%) risk classification prevailed and hypertension (18.3%) was the most common Comorbidity. The most frequent pain intensity was moderate (25.9%). In the red category, patients presented a higher percentage of absence of pain; in the blue, mild pain; and in the green, yellow and orange categories, there was a greater percentage of intense pain (p < 0.0001). Conclusion: among the patients who presented pain, the majority reported moderate intensity. Regarding risk categories, most patients in the red category did not report pain. Those who were classified as green, yellow and orange, reported mostly intense pain. On the other hand, patients in the blue category reported predominantly mild pain.


Introduction
The situation of emergency services has been a matter of concern to the health community and to society. The demand for these services has increased due to high rates of urban violence, accidents and aging populations with a consequent increase of chronic diseases (1)(2) . Furthermore, many of the cases received in emergency units are the result of low complexity diseases, referred to these services due to lack of structure in the basic health network, that could be resolved in basic or specialized units, or emergency services of lower complexity (3) . This demand profile characterizes the Emergency Service (ES) as one of the main entry points to the health system (1) .

The reception of patients with Risk Assessment and
Classification (RRAC) was implemented to improve care in Emergency Services and consists of a system of initial evaluation of patients' complaints with the main objective of providing care according to the level of severity, and no longer on a first-come, first-served basis (1,4) .
The RRAC performed by nurses is a tool to recognize patients who must be assisted within the shortest time possible. In the 1990s, several countries adopted and improved scales to classify patients' risk. to the severity of their situation (1) .
Among the health professionals authorized to conduct the risk classification process, after proper training, are the nurses. In a brief nursing consultation, the situation of the patient is evaluated through a physical examination focused on the complaints, personal history, and vital signs based on established protocols. After this process, the patient is informed about the estimated waiting time. When the complaint is painful, the intensity of the pain should be evaluated according to the protocol adopted at the institution (5) .
Pain is a symptomatic response of the organism, being a relevant sign at the moment of the evaluation.
The search for emergency services is motivated by painful complaints which can be perceived in different ways. Thus, nurses must be aware of the time of their evaluation to provide the best care (6) .
Pain is defined by the American Pain Society as the fifth vital sign, and should be assessed along with temperature, respiratory rate, pulse and blood pressure.
Its evaluation helps to diagnose the problem presented by the patients (6) . Nurses should investigate pain and use of instruments to assist in its measurement, as well as in the response to analgesia. Pain relief provides comfort and well-being to the individuals and promotes health during hospitalization or at home (7) .
Pain in the ES, in most cases, is acute and may be related to trauma or inflammatory processes (6) .
Inadequate management of pain can cause problems such as increased blood pressure, heart rate and respiratory rate, resulting in worsening of the patients' condition (6) .

Some obstacles have been identified in the evaluation of painful complaints of patients in Risk
Classification, including the patients' impaired ability to reliably report pain due to altered emotional state, anxiety due to the affected physical and mental state, and the type of approach by the professionals, because technical language sometimes makes it difficult for the patients to understand what is said. In addition, in ESs, there are many tasks to be performed in a short period of time as a result of the excessive flow of patients and need for fast care measures that can lead to an impaired evaluation of pain as a vital sign (6) .
The management of pain in Emergency Services is complex because of its subjectivity, and still remains a challenge. The quality of safe and effective care can avoid complications resulting from prolonged pain, as well as provide the patient with greater comfort in the care in these places (8) .
The objective of this study was to correlate the risk  Analysis of Variance (ANOVA) was used to compare pain intensity with age. Pain intensity was correlated with sex, signs and symptoms, history of cancer, category of risk classification and medical specialty using the Chi-Square test and when necessary the Likelihood Ratio test. A significance level of 5% (p-value < 0.05) was adopted.

Results
Among the 611 patient records analyzed in this study, the mean age was 42.1 (17.84) years; the majority were women 366 (59.9%); and the duration of complaint to receive care ranged from 1 to 365 days.
Patients with no pain had a significantly higher age than those with moderate pain, with men presenting a higher percentage of absence of pain while women had more often intense pain (Table 1).
Patients classified in the red category had a higher percentage of absence of pain, whereas patients classified as green, yellow and orange had severe pain and those as blue had mild pain (Table 1).
Patients attended by psychiatry presented a higher percentage of absence of pain and those attended by orthopedics, of intense pain (Table 1).
In relation to signs and symptoms, patients with respiratory symptoms had a higher percentage of absence of pain, while those without these symptoms had a greater percentage of intense pain ( Table 2).
Patients who were not able to move their bodies and those with psychiatric and neurological symptoms had a higher percentage of absence of pain, while those with an inability to move part of the body had a higher percentage of moderate and intense pain ( Table 2).
Patients who reported nausea had a higher percentage of intense pain, and those without nausea had a higher percentage of absence of pain and moderate pain ( Table 2).

Discussion
The demand for urgent care has increased and most patients report pain at the time of RRAC. Based on this complaint, resources are used to classify and organize the priorities of these patients. Pain is one of the main reasons that can generate inabilities and cause human suffering, impacts the quality of life, and can generate psychosocial and economic repercussions (10) .
In this study, women predominated in the demand for Emergency Service in relation to men Some factors that may explain this is the resistance of men to seek health care due to societal taboos and gender-related sociocultural factors in which diseases are considered a sign of fragility and the search for medical services, a demonstration of weakness (11) .
In the risk classification categories, the majority of patients were classified as green (58.9%), followed by yellow (22.7%), orange (7.9%), blue (5.9% ) and red (4.6%), a similar result to another national study conducted in a public hospital in Diamantina, Minas Gerais, Brazil, in which low complexity patients were also the majority (12) . Thus, as already described in another study, one of the causes of overcrowding in ESs is the presence of less urgent cases that could be solved in primary health care (1) . pain, concluding that pain intensity was related to the main reason for seeking emergency care (10) . Although pain is one of the main reasons for seeking emergency care and despite the existence of scales to assess its intensity, few professionals use these tools during care (7) .
A study that evaluated the knowledge of nurses about pain showed that 73.3% never participated in a training on pain assessment and that their knowledge about pain management was medium (18) . This shows the importance of nurses to develop skills to make a complete evaluation of complaints, without underestimating the patients' pain that can often be indicative of the severity of his health condition (10) .
Participants in this study who did not present pain were significantly older than those with moderate pain.

A study carried out in an Emergency Service in Aracajú
showed that patients with moderate pain complaints were younger than those who did not present pain, corroborating the results of the present study (10) . Studies show that age is a factor that may modify the experience of the patient regarding pain and the effect of aging may make them less sensitive to painful stimuli (19) .
Male patients had a higher percentage of absence of pain, while female patients had a higher percentage of intense pain. Pain is a personal and subjective experience, not only resulting from characteristics of tissue injury, but also integrating individual emotional and cultural factors (7) .
The patients in this study classified in the red category did not complain of pain. This is due in part to the fact that patients classified as red are at high risk of death and their pain assessment may be impaired due to prioritization of care, which is started even before the patient is registered in the hospital (10,12) . Furthermore, it is common for severe patients to present altered consciousness, what prevents pain assessment (20) .
Patients classified as green, yellow and orange had a higher percentage of intense pain. The process of pain recognition informed at the moment of assessment is subjective and individual and may influence the risk category attributed to the patient (21) . In this study, physiological repercussions such as increased blood pressure, tachypnea, tachycardia, nausea, as observed in our study, among others. It is up to nurses to determine, by means of their perceptions, the proper category and waiting time to provide care for the patient (21) .
Pain is a common symptom presented in ESs.
Although it is often underestimated, poorly assessed and treated, priority judgment often may not be appropriate in that situation. The nurses' ability for not to interfere in the report of the pain intensity is still an obstacle to be faced. The application of a protocol for the adequate management of pain by the nurses can avoid delays in the treatment with analgesics and improve the quality of patient care (21) .
Patients attended by the medical specialty of   (24) . In addition, medications commonly used for pain control such as opioid analgesics often cause nausea as a side effect (25) .
Pain in cancer patients ranged from absence (48%) to severe (40%) intensity. This complaint may vary according to the stage of the disease, and studies show that 90% of patients in advanced stages of cancer feel more intense pain (24) . The control of cancer pain can be difficult and pain is often the final result of a process involving emotional, spiritual, cognitive and sensory aspects. Pain, in these cases, may be associated with disease progression and cause hopelessness and fear in the patients; these cases require a careful and differentiated approach to pain management (26) .
The limitations of this study were its realization in a single center, collection of data from medical records which were often incomplete and illegible and use of RRAC protocol with adaptations to the needs of the Institution limiting the comparison with other studies.
This study may contribute to practice insofar as its findings demonstrate the importance of professionals working in RRAC to be able to use pain intensity scales because this symptom is an individual and subjective experience, and its identification may influence the category of severity attributed and the experience of the patients regarding the quality of care received.
Since pain is one of the main reasons for seeking ESs, it is paramount that nurses have knowledge about it. In most cases, nurses are the professionals responsible for the first care measures and they define the flow of the patients in the service. All patients have the right to express their pain and receive treatment for Viveiros WL, Okuno MFP, Campanharo CRV, Lopes MCBT, Oliveira GN, Batista REA.
this complaint, and the nurses and the multiprofessional team must implement effective strategies to relieve pain avoiding deleterious effects resulting from this symptom and providing patients with humanized care.

Conclusion
In this study, the pain intensity reported by patients was most frequently of moderate intensity. The association of pain with the risk classification categories showed that patients classified in the red color showed, in most cases, absence of pain; those classified in the blue color had mild pain; and those classified in the green, yellow and orange colors had severe pain.