Article Text

Protocol
Pain Neuroscience Education in elective surgery patients: study protocol for a randomised controlled trial
  1. Raquel Pereira de Souza1,
  2. Laura Borges Lopes2,
  3. Anne Caroline Nunes Carmo2,
  4. Paula Muniz Machado2,
  5. Joanlise Marco Leon de Andrade3,
  6. Mani Indiana Funez1
  1. 1School of Ceilândia, Universidade de Brasilia, Brasilia, Brazil
  2. 2School of Ceilândia, University of Brasilia, Brasilia, Brazil
  3. 3Department of Statistics, University of Brasilia, Brasilia, Brazil
  1. Correspondence to Dr Mani Indiana Funez; mani{at}unb.br

Abstract

Background Pain Neuroscience Education (PNE) consists of an educational strategy that seeks to understand the biological processes of pain and how to control it. The main objective of this study will be to evaluate the impact of PNE on outcomes related to the postoperative period. The hypothesis is that the intervention may positively influence postoperative recovery, contributing to pain control, clinical indications, acceptance and consumption of analgesics and other pharmacological drugs that contribute to its control, as well as psychological aspects, such as anxiety, depression and pain catastrophising.

Methods and analysis This will be an open, parallel, multicentre and randomised controlled clinical trial. A total of 100 participants aged between 18 and 59 years of age, of both genders, who are going to have elective general surgery will be evaluated. The intervention group will participate in a preoperative pain neuroscience educational session and also receive usual preoperative care, while the control group receives usual preoperative care as well. The educational session will last 30 min and consists of a video (5:20 min), a questionnaire about the content, time for participants to express their beliefs, thoughts and doubts. Participants will be evaluated preoperatively and there will be one postintervention evaluation. The intensity and characteristics of pain and anxiety are evaluated as primary outcomes. As secondary outcomes, pain catastrophising and depression are taken into account.

Ethics and dissemination The project was approved by the Research Ethics Committee of the Faculty of Ceilandia, the Research Ethics Committee of the Institute of Strategic Health Management of the Federal District and the Research Council of the Hospital of Brasília—Rede Dasa (CAAE: 28572420.3.0000.8093). Recruitment began in June of 2023. All participants were included in the study only after their written consent. All data obtained will be analysed and distributed through publication in journals and at scientific events.

Trial registration number Brazilian Registry of Clinical Trials (ReBEC) (RBR-23mr7yy).

  • Health Education
  • PAIN MANAGEMENT
  • Nursing Care
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STRENGTHS AND LIMITATIONS OF THIS STUDY

  • The proposed intervention will bring an educational approach to pain neuroscience.

  • The content will be accessed by an audiovisual resource, which provides accessibility.

  • The impact of the intervention on acute postoperative pain will be evaluated.

Introduction

Background and rationale

Pain is one of the most frequent complications during the postoperative period and results from tissue damage that causes an inflammatory reaction, involving peripheral and central sensitisation.1 It involves unpleasant sensory, emotional and mental experiences associated with autonomic, physiological and behavioural responses.2

Some risk factors influence the severity of postoperative pain. They may be patient demographic characteristics (such as age and gender), type of surgery, presence of preoperative pain, psychological factors (anxiety, stress, depression and pain catastrophising) and pain perception, in addition to genetic factors.3 4 Knowledge of these risks helps to improve tools that individualise patient care and may contribute to reducing the severity of pain after surgery.5

Ineffective treatment can result in chronic pain in addition to other complications that influence the clinical evolution of the patient after surgery, subsequently impacting costs and length of hospital stay.2 6

The multimodal analgesia approach is recommended in the management of postoperative pain. Nonetheless, its therapy may represent a challenge and needs advances.7 Perioperative pain control protocols should consider their characteristics when choosing medications, and the analgesic ladder can be used as a reference. It is essential to incorporate non-pharmacological approaches to pain prevention and treatment.8 9 In this sense, nurses together with other members of the healthcare team, can contribute to pain management and perioperative patient education.10

Pain Neuroscience Education (PNE) can be used as a perioperative educational action that seeks to understand pain through the understanding of its biological processes and mechanisms that help in its reduction.11 12

PNE has been shown to be effective in terms of reducing complaints of pain intensity, disability, psychological aspects and movement limitation.12–27 There are several studies that address PNE. However, when it comes to the surgical context, studies in the area of orthopaedics prevail, whose participants have the characteristic of chronic pain. The majority perform surgery as part of pain treatment and find improvements that, in most studies, cannot be attributed to the PNE intervention but rather to surgical treatment.27 Therefore, there is a lack of studies that analyse the possible benefits of PNE in the context of acute postoperative pain and we did not find studies with general surgery patients.

Objectives

The objective of the study will be to evaluate the impact of PNE on outcomes related to the postoperative period. The hypothesis is that the intervention may positively influence postoperative recovery, contributing to pain control in terms of intensity and quality, clinical indications, acceptance and consumption of analgesics and other pharmacological drugs that contribute to its control, as well as psychological aspects, such as anxiety, depression and pain catastrophising.

Methods and analysis

Trial design

This will be an open, parallel, multicentre, randomised, controlled clinical trial. The protocol followed the recommendation of SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials, figure 1) and recommendations for supplementing the Consolidated Standards of Reporting Trials checklist considered in pain clinical trials.28 The study was registered with the Brazilian Registry of Clinical Trials (ReBEC, as per its Portuguese acronym) (RBR-23mr7yy).

Figure 1

Schedule of study enrolment, interventions and evaluations. PNE, Pain Neuroscience Education.

Study setting

The study will be carried out with patients undergoing elective general surgeries in two public hospitals and two private hospitals in the Federal District of Brazil.

Sample size

The primary outcome requiring the largest sample size is the Short-Form McGill Pain Questionnaire (SF-MPQ) difference (difference between measurements at intensive care unit discharge and before surgery). The sample size was estimated using G*Power software, V.3.1.9.6.29 It was calculated in order to detect a moderate effect with a minimal clinically important difference (MCID) of 1.5 units in the SF-MPQ difference,30 assuming an SD of 2.5 for both study groups (intervention and control), a significance level of α=5% and a power of 80% in a two-sample t-test, which yielded 45 individuals in each group. The enrolment goal was set at 100 patients (50 per group) to allow for a 10% dropout rate.

Outcome measures

Since the intervention involves a preoperative session with the researcher, all subjects will be analysed in the treatment arm to which they were randomly assigned (figure 1). Therefore, no deviation from the intention-to treat approach is anticipated.

Primary outcomes

Pain intensity and characteristics will be evaluated using the SF-MPQ, along with anxiety levels, using the Hospital Anxiety and Depression Scale (HADS).

Secondary outcomes

Pain catastrophising will be evaluated using the Pain Catastrophizing Scale (PCS), and depression using HADS.

Covariables

Sociodemographic characteristics (age, sex, education level), clinical information on the surgery such as type of surgery, adherence and use of pain management pharmacological drugs and fear of movement related to surgery pain will be evaluated in the study. Effect modification and confounding will be assessed by adjustment and/or stratification by all covariates as potential effect modifiers or confounders.

Recruitment

Recruitment began in June 2023 and is expected to last until July 2024 and takes place daily with the help of service teams that inform the research group in relation to schedules for elective general surgeries.

Participants

Eligibility criteria

The following items are adopted as inclusion criteria: Age from 18 years of age to under 60 years of age, of both genders, and patients undergoing elective general surgery. Exclusion criteria are: Patients with an inability to understand and/or answer questions and questionnaires, continuous use (>3 months) of analgesic and/or anti-inflammatory drugs in the preoperative period, people with a history of pain for more than 3 months in the preoperative period and comorbidities, such as neuropathies, fibromyalgia, neoplasms with a history of pain or active inflammatory disease.

The scale or test to determine the previous cognitive level will not be used. The research team will analyse the institution’s medical records and preoperative care documents to verify patient characteristics that may influence the data. In the surgical context, patients with cognitive impairment will always be accompanied by a family member or caregiver and researchers will be attentive to these characteristics. In addition, socio-demographic data will be analysed later, including the level of education. And if necessary, such variables will be analysed as a confounding variable.

The execution team is composed of six researchers: (a) two nurses studying for a master’s degree and (b) two volunteer research nurses, all with experience in pain research, who will conduct recruitment, intervention and evaluation; (c) one statistician professor, specialist in health data analysis, who will conduct data analysis; (d) one nurse professor, specialist in pain research, responsible for managing the project, supervising and funding acquisition.

After the patients are admitted, the researcher assigned to carry out the intervention and preoperative data collection requests their consent to participate (online appendix 1).

Patient and public involvement

Patients and the public were not involved in any way is this study.

Allocation

Participants will be divided into a control group and an intervention group, in a ratio of 1:1. Randomisation is performed using Research Randomizer software with fixed-size blocks consisting of 10 numbers.

After using the software, the researcher in charge, without the knowledge of the other researchers, will determine for each block whether odd or even numbers will be defined as the control group or the intervention group. The definitions of each block are distinct and individualised.

For all those who are eligible and agree to participate in the study, randomisation will be performed, where an allocation number is assigned, and the researcher responsible for the collection will only know which group this number/participant belongs to after recruitment, thus guaranteeing secrecy. The group is kept confidential until the moment of the preoperative intervention. The researcher responsible for the allocation, preoperative data collection and application of the intervention will not participate in the postoperative evaluation.

Blinding

Because of the nature of the educational intervention, participants cannot be blinded to allocation.31 As previously described, the intervention will be carried out preoperatively by a different researcher. Accordingly, it is expected to ensure the blinding of the evaluator who collects data postoperatively. The participants will be instructed not to inform the other researchers to which group they have been assigned or even which intervention will be carried out. The information collected in the instruments is filled out in an electronic form, assigning a code and generating spreadsheets with the data automatically. In this way, the data are analysed while maintaining allocation blindness. Therefore, the researcher analysing the data remains blinded when assigning participants to groups.

Interventions

After evaluating the eligibility and allocation criteria, the participants will be divided as follows:

Intervention group

Preoperative education in pain neurosciences and usual preoperative care: The proposal for PNE will consist of an individualised preoperative meeting between researcher and participant. The educational session will have an audiovisual resource (video) prepared by the research group that has information about the neurophysiology of pain, the pathophysiological mechanism of postoperative pain, potential central sensitisation factors (emotions, stress and perceptions of the disease), the role of the brain in pain perception, psychosocial factors related to pain, cognitive and behavioural responses related to pain and surgery and the use of analgesics during the postoperative period. The material will be prepared based on studies in the field of Neuroscience of Pain, the book ‘Explain Pain’ and the principles of perioperative nursing care focused on pain control.12 32 33 The following concept of PNE was used: “a range of educational interventions that aim to change one’s understanding of the biological processes that are thought to underpin pain as a mechanism to reduce pain itself. It draws on educational psychology, in particular conceptual change strategies, to help patients understand current thought in pain biology”.12 32 The video will last 5 min and 20 s and will be shown to the participant after evaluating the preoperative variables. The topics covered in the video and its duration will be as follows: pain as an individual experience (25 s), how pain works (1 min and 30 s), importance of understanding the painful process (30 s), pain in surgery and inflammatory process (50 s), pain as a protective mechanism (30 s), fear of movement (15 s), coping with pain (30 s) and pain assessment (50 s). At the end of the video, in addition to time for comments and questions, the researcher will review important points of the intervention and deliver the material to patients in writing. Participants will then be asked to answer questions to determine their level of understanding of the sessions. The biopsychosocial perspective of the patient based on their beliefs or knowledge will be considered during all the intervention session. The questionnaire presents statements about the topics covered in the intervention, and the patient can choose between true or false. The questions to be answered are as follows: ‘Feeling pain after surgery is not normal and you cannot do anything to improve it, only professionals,’ answer: false; ‘Your attitudes, thoughts and emotions impact the intensity of the pain,’ answer: true; ‘Healing demonstrates tissue recovery, which promotes pain reduction,’ answer: true; ‘Your body systems do not help protect and recover after surgery and the inflammation generated is a bad thing,’ answer: false and ‘Although pain is a natural and protective process, you should not let it increase each time. Furthermore, there are several medications to reduce the painful sensation. Asking for help from the professional who accompanies you is essential,’ answer: true. The total preoperative meeting time for this group is estimated at approximately 30 min. Participants will be approached in the unit’s preoperative preparation area, in individual boxes, moments before entering the surgical centre. The intervention followed the recommendation of TIDieR.34

Control group

Usual preoperative care: The standardised intervention of the service takes place through preoperative guidance provided by the multidisciplinary team about surgery, anaesthesia, preoperative and postoperative care, pharmacological drugs, procedures and examinations. The researcher and participant will have a preoperative meeting time estimated at 15 min to collect data regarding preoperative variables.

Data collection for both groups uses its own instrument, which contains data filled out by the researchers based on information obtained from medical records and interviews with the participants. The preoperative evaluation includes sociodemographic and clinical information. Postoperative data collection will take place during the first 48 hours after surgery.

Postoperative care and pain control care are identical in both groups and follow the usual care offered by the institution. The instruments used to evaluate the results will be used by the groups both preoperatively and postoperatively. The institutions where the research takes place are aware that patients who need any concomitant treatment that may interfere with the outcomes must be informed to the researchers who will evaluate the cases for decision making regarding the continuation of the research.

Collection will be interrupted in cases where the participant is discharged from the hospital before the researcher’s postoperative visit. It will also be suspended if the participant presents haemodynamic instability or another situation in which his or her clinical condition is compromised by the interaction with the evaluator, putting him or her at risk, or even if he or she demonstrates discomfort when answering the research questions.

Data collection and management

Primary outcomes

Pain

The SF-MPQ is used to obtain three different pain indexes.35 36 This multidimensional instrument evaluates pain using descriptors that are selected by the participant. There are 15 descriptors divided into subgroups: sensory (11 descriptors, from 0 to 33 points) and affective (4 descriptors, from 0 to 12 points). Each descriptor receives an intensity rating and can score from 0 to 4 (0=none, 1=mild, 2=moderate and 3=severe). The pain index of each individual is obtained by summing the intensity values of the chosen descriptors. The higher the score, the greater the pain intensity. The maximum possible total value is 45 (0–45 points). The SF-MPQ also includes usage of the Visual Analogue Scale, where the participant will indicate how his or her pain has been during the last few days, ranging from no pain to the worst possible pain (0–10 points). Present pain intensity also includes the SF-MPQ instrument, ranging from 0 to 5 points, where 0 corresponds to no pain and 5 corresponds to excruciating pain.

Anxiety

The HADS37 38 will be used to measure anxiety. This scale has 14 items that deal with anxiety (HADS–A, 7 items) and depression (HADS–B, 7 items) and appear alternately. The interviewees will answer seven questions from each subscale with a score from 0 to 3 in intensity. When analysing anxiety and depression in separate groups, the global score for each subscale can reach 21 points. For this study, the classification ‘without anxiety’ and/or ‘without depression’ will be adopted for scores from 0 to 8 and ‘with anxiety’ and/or ‘with depression’ for scores equal to or higher than 9.37 38 The MCID considered for HADS will be 1.5 points.39 40

Secondary outcomes

Catastrophising

The PCS has 13 items listed on a Likert Scale ranging from 0 (minimum) to 4 (very intense) points. The scale is divided into three domains: helplessness (items 1–5 and 12), magnification (items 6, 7 and 13) and rumination (items 8–11). The score is calculated by summing the items. The higher the score, the greater the indication of catastrophic thoughts; it is possible to score from 0 to 52.41 The MCID value considered for PCS will be 1.9–13.6 points.30

Depression

This outcome will be evaluated using the HADS as described above.

Covariables

Pain characteristics

The aspects of pain evaluated in a specific instrument will be pain location, duration, times of improvement or worsening and vital signs.

Fear of movement related to pain

The patient will be asked in the postoperative period if he or she is afraid of moving himself or herself and feeling pain.

Consumption of drugs for pain

In the postoperative period, the prescription and administration of non-opioid analgesics, opioids, non-steroidal anti-inflammatory drugs, steroidal anti-inflammatory drugs, antidepressants, gabapentinoids and other drugs that may be prescribed for pain control will be checked.

Clinical and sociodemographic characteristics

Based on the preoperative interview, using an instrument developed by the research team and analysis of the medical records, the following data will be collected: initials of the patient, gender, age, date of birth, date of admission, colour or race, place of birth, marital status, level of education, profession or occupation, religion, presence of comorbidities and risk factors (alcoholism, smoking, obesity and malnutrition).

Perioperative information

The information collected through interviews using an instrument prepared by the research team and analysis of medical records, in the preoperative period will be reason for admission, length of stay, medical diagnosis (if any), proposed surgical procedure, previous surgeries, medication currently being taken. Information regarding the intraoperative period will be collected through the electronic medical records of the patient, namely date of surgery, time of admission to the postanaesthesia care unit, surgery performed, duration of surgery, American Society of Anesthesiologists classification, type of anaesthesia, consumption of intraoperative and postoperative analgesics, whether there was insertion of a drain, accomplishment of an ostomy, maintenance of an epidural catheter and restriction of movements in the postoperative period.

In order to retain participants’ interest, the researchers will explain the benefits of the study, emphasising that the research can contribute to the development of new information on the influence of PNE in postoperative outcomes. This will enable the creation and implementation of educational models to train professionals and, consequently, benefits patients, who will receive more qualified care and be able to improve their self-care given the information received. In addition, all study participants will have the opportunity to be evaluated by the research group during the preoperative and postoperative periods, where it will be possible to identify any healthcare needs that will be presented to the service team.

The participation of service collaborators is fundamental for the recruitment and follow-up of the participants during the study. As for the researchers, a scale was made so that data collection would occur according to the forecast for elective surgeries.

Data management

The data will be entered in a Microsoft Forms form. Each instrument to be used in the research will be entered as a questions. For this purpose, mobile data devices are used, and the forms are stored in the cloud. Subsequently, these data will be extracted into Microsoft Excel format, checked and compiled to constitute the database of the study. The database will be stored in a safe and accessible place and maintained for a period of 5 years after the conclusion of the study.

The information collected will be kept confidential by the team of researchers. The identification of the participants will be identified by a previously assigned number. Access to the electronic forms and the database will be password restricted to authorised users only and requires the login and password of the e-mail address of the institution. The results will be published in a way so as not to undermine the confidentiality of the participants.

There will be a follow-up of all participants who sign the consent form during the admission period, as well as between the intervention and the postoperative data collection, where any problems seen will be reported to the hospital staff and to the ethics committee. Considering that the interventions will not be of physical or organic origin, the risks of the research are of a psychological, intellectual and emotional nature, including discomfort when answering the questions, embarrassment, changes in self-esteem caused by past memories, fatigue and breaches of confidentiality. In addition, the intervention will contain printed resources and audiovisual media, which may make understanding easier for patients who are unable to read. The researchers will be attentive to verbal and non-verbal signs of discomfort made by the participants, who will be guaranteed privacy and freedom not to answer questions that may embarrass them, limited access to the collected data, reading of the resources and clarification of queries in relation to PNE.

The researchers who will carry out the data collection will be the same ones from the beginning to the end of the study, having been previously trained and following pre-established operational procedures. The participants will be evaluated at specific times, not continuously requiring evaluation during the proposed intervention. The main researcher will be available to clarify any queries and answer any questions that may arise during the research.

Statistical methods

Exploratory data analyses will include the calculation of means and SDs or medians and IQRs (for non-normal distributions) for quantitative variables and counts and percentages for categorical variables. Quantitative variables will be compared between the two study groups (intervention and control) by Student’s t-tests or Wilcoxon-Mann-Whitney tests. As for categorical variables, χ2 or Fisher exact tests will be carried out. Pearson or Spearman correlation estimates and tests between quantitative variables will also be obtained. Results with p values <0.05 will be considered statistically significant. All analyses will be implemented by either IBM SPSS Statistics (IBM) or R software.42

For each outcome of interest, multivariate analyses will be performed to account for the effects of demographic and other clinical variables and potential confounding factors. Secondary outcomes will also be evaluated.

Participants who miss their follow-up for any reason (withdrawal, hospital discharge before postoperative evaluation or concomitant treatment that influences the evaluated outcomes) will be excluded from the final sample. The number and reason for missed follow-ups will be shown in the results.

Ethics and dissemination

The study will be conducted in accordance with Resolution 466/2012 of the National Health Council: Guidelines and Regulatory Norms for Research Involving Human Subjects. The participants will be included in the research after signing the consent form. The project was approved by the Research Ethics Committee of the Faculty of Ceilandia, the Research Ethics Committee of the Institute of Strategic Health Management of the Federal District and the Research Council of the Hospital of Brasília—Rede Dasa (CAAE: 28572420.3.0000.8093).

If there are any requirements for relevant modifications, which have been previously checked in the partial analyses and discussed within the research group, and if they influence the methodological aspects, an amendment will be prepared to be considered by the Ethics Committee. In situations where the changes deal only with administrative topics, the entire group will be consulted and the change will be recorded.

The researchers will accompany the participants during the research, and, after the study, they will be available at any time for questions related to the impact of the study. The telephone contacts and electronic and institutional addresses of the researchers will be available to the participants, as are those of the Ethics Committee that approved the project. There will be no payment or rewards for participation in the study. The participant will not have additional expenses.

The data will be available through password access to the main researchers on the platform where it will be stored. Sharing will be restricted to official publications with the knowledge of all researchers.

All the data obtained will be analysed and distributed through publication in journals and at scientific events. In the services where the study will be carried out, it is proposed to present the data and make it available to contribute to possible clinical protocols that are of interest.

After the end of the analysis and publication of the results, the anonymised database and the statistical calculations used will be available on request to the researchers.

Ethics statements

Patient consent for publication

References

Supplementary materials

  • Supplementary Data

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Footnotes

  • Contributors RPdS, LBL, ACNC and PMM: conceptualisation; methodology; visualisation; roles/writing—original draft; writing—review and editing. JMLdA: formal analysis; methodology; visualisation; roles/writing—original draft; writing—review and editing. MIF: conceptualisation; funding acquisition; methodology; project administration; supervision; visualisation; roles/writing—original draft; writing

    —review and editing.

  • Funding The study is funded by the Research Support Foundation of the Federal District under protocol number 00193-00001758/2022-22 and the Scientific Initiation Program of the University of Brasilia.

  • Competing interests None declared.

  • Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Supplemental material This content has been supplied by the author(s). It has not been vetted by BMJ Publishing Group Limited (BMJ) and may not have been peer-reviewed. Any opinions or recommendations discussed are solely those of the author(s) and are not endorsed by BMJ. BMJ disclaims all liability and responsibility arising from any reliance placed on the content. Where the content includes any translated material, BMJ does not warrant the accuracy and reliability of the translations (including but not limited to local regulations, clinical guidelines, terminology, drug names and drug dosages), and is not responsible for any error and/or omissions arising from translation and adaptation or otherwise.