Knowledge and attitude of candidates to gastroplasty about perioperative: randomized clinical trial.

OBJECTIVES
to evaluate the effectiveness of educational intervention in the knowledge and attitude of candidates for gastroplasty.


METHODS
randomized controlled clinical trial with 56 preoperative patients (intervention=28; control=28). The control group received routine care from the health institution and the intervention group participated in a book-mediated educational intervention. Forms were used for clinical-epidemiological characterization and evaluation of knowledge/attitude about bariatric surgery, which were reapplied seven weeks after intervention. RBR-297fzx.


RESULTS
in the pre-test there was no significant difference between the groups (p=0.254). In the post-test, the group that received verbal guidance had a mean score of 19.5 (± 6.17) and the group reading the booklet averaged 31.1 (± 2.96), p=0.000. The attitude is adequate, especially for care such as vitamin supplement intake, water intake and physical activity practice.


CONCLUSIONS
the educational intervention mediated by booklet was effective in improving knowledge and attitude when compared to verbal guidance. Thus, it can be replicated during the preoperative preparation.


INTRODUCTION
Bariatric surgery is considered the best option for patients at high risk of morbidity and mortality who do not present weight loss with conventional treatments and suffer from complications of obesity (1) . However, for its performance, preoperative preparation is necessary, in which the patient must receive information concerning the surgical procedure (2) .
Surgical intervention improves the quality of life and self-esteem, however, it causes physiological changes that must be clarified to candidates for surgery, and also offer risks and complications. These individuals must be aware of the perioperative phases and their role as active agents in the treatment and adherence to the recommendations received for therapeutic success (3) .
In the preoperative period, it is crucial to develop health education proposals, including the use of educational technologies, to guide bariatric surgery candidates to disseminate and expand knowledge about the main adaptations, benefits, risks, and challenges. The information included in educational interventions should not be limited to the most popular topics such as physical health, complications, and diet, but should also include psychosocial preparation and lifestyle changes (4)(5) .
To meet the educational needs of this public, the technological resource created and validated, entitled "Bariatric surgery: care for a healthy life", stands out, which guides and encourages adherence to care in the perioperative period (6) . In a previous study, it was shown to be suitable for use by health professionals with candidates for bariatric surgery (6) .
Given the above, the following question came up: is the educational booklet more effective for improving the knowledge and attitude of patients in the preoperative period compared to the verbal guidance provided in the service routine?

OBJECTIVES
To assess the effectiveness of an educational intervention on the knowledge and attitude of candidates for bariatric surgery.

Ethical aspects
The study was approved by the Research Ethics Committee of the Universidade Federal do Ceará and in the Brazilian Clinical Trials Records (RBR-297fzx).

Study design, setting and period
Controlled Randomized Clinical Trial (RCT) carried out from June to August 2017 at a reference institution for bariatric surgery in the State of Ceará. In this institution, the perioperative period encompasses three moments: pre-operative (mediate and immediate), trans-operative and postoperative (immediate, mediate, and late). It starts at the first consultation with the surgeon and lasts throughout the patient's life in the follow-up consultations of the late postoperative period. Thus, the follow-up of the present study occurred in the preoperative period.

Participants
The target population was composed of patients in the mediate preoperative period. Inclusion criteria were age over 18 years; be enrolled in the obesity program of the institution under study and be literate. The exclusion criterion was to use the intragastric balloon.
The exclusion criteria were: gastroplasty; placement of the intragastric balloon; and unsuccessful telephone contact after at least 10 attempts, which included calls identified as out of the area, disconnected phone or not answered.
The sample calculation was achieved using a 95% confidence coefficient (Zα=1.96), 80% power (Zβ=0.84), p=10% and d=25%. A sample number of 27 patients was established for the control group (CG) and 27 patients for the intervention group (IG). Considering a 20% of losses in the follow-up, it was decided to invite the 66 eligible patients, equally distributed between CG and IG to minimize the percentage of losses during the follow-up and optimize the statistical interpretation between the data.
After the beginning of the data collection, there was a sample loss in both groups, associated with the placement of the intragastric balloon and leave for the bariatric surgery, which resulted in a sample of 56 participants (intervention=28 and control=28).
The process of including patients in the groups took place through randomization using the Research Randomizer software (www.randomizer.org). For this, the list of patients waiting for bariatric surgery was obtained from nursing management. All participants on the list were orderly numbered and then submitted to the randomization process, with 1:1 allocation in CG and GI.
The allocation concealment was enabled from the moment of randomization and this process was carried out by the support researcher. The two lists, one with the participants of the CG and the other with the participants of the IG, were placed in thick envelopes and delivered to the main researcher. Through data collection, the researchers performed both strategies (interview and physical examination) with the groups and it was not revealed whether it was intervention or control. Thus, only the main researcher knew about the difference between patients in the groups.
The moment of the initial collection (baseline) and the implementation of the educational intervention with the IG were made exclusively by the main researcher. The follow-up of the data collected through the face-to-face and telephone meetings was carried out by two other properly trained support researchers, who did not join in the moment of randomization.

Data Collection Instruments
The instrument, developed and validated by the research group of nursing interventions in the care of adults in critical situations at the Universidade Federal do Ceará (UFC), was divided into two parts: sociodemographic characterization and assessment of knowledge and attitude about bariatric surgery. The validation of the instrument was done by three professors from the UFC nursing course who had expertise in validating instruments and publishing on educational technologies.
This instrument was developed based on the educational booklet content, the integrative review on bariatric surgery, and perioperative care. Overall, it encompassed 43 questions, of which 35 were about knowledge and eight about attitude, all with True or False answers. Of the questions regarding knowledge, six included general aspects of bariatric and preoperative surgery; 11 referred to postoperative hospitalization; 11 to the home postoperative period and seven to the late postoperative period. The eight questions about attitude addressed the relevance of food, hydration, physical activity, psychological support, consultations, and postoperative care.
Suitable knowledge was defined as a total of correct answers equal to or greater than 70%. The attitude was defined as suitable when the individual said it was "necessary" or "very necessary" in 70% of the guidelines on care in the postoperative period of bariatric surgery; and an unsuitable attitude was when the individual indicated that it was "little necessary", "unnecessary" or answered "not having an opinion" in less than 70% of the proposed actions.

Study protocol
The baseline moment (M0) took place at the institution's outpatient clinic, with the CG and IG patients, who did not know which group they belonged to, through interviews and filling out the instruments, taking approximately 20 minutes for each participant, individually.
After M0, the CG received routine care from the institution's multi-professional team, with verbal guidance during consultations and monthly lectures with surgeons and psychologists on bariatric surgery, with a focus on surgical techniques and weight loss. With the CG, a meeting was scheduled to filling out the knowledge and attitude instrument again, seven weeks after doing it for the first (M0), so that this procedure had a time interval similar to that done in the IG.
The IG, in addition to the same routine care as the aforementioned multi-professional team of the institution, at the moment 1(M1), underwent an educational intervention based on the collective reading of the booklet entitled "Bariatric surgery: care for a healthy life" on days and times scheduled with all group participants during their mediate preoperative. There was a need to schedule four meetings since the contents of the booklet encompasse the entire perioperative process of bariatric surgery. The first three meetings were weekly and sequential, with information on the preoperative, transoperative and postoperative phases, consecutively. The last meeting, called moment 2 (M2), for filling out the instrument again, was scheduled for 30 days after the end of reading the booklet. Thus, there was a seven-week interval between the first measurement/application of the instrument in M0 and the second application, in M2.
The total reading time of the booklet is 20 minutes, on average. As the content is very broad, the meetings were distributed according to the themes of the perioperative phases for better understanding and assimilation of information. Each participant took, on average, five to eight minutes to read the selected chapter. The process of a collective reading of the booklet took place in the auditorium of the reference hospital, with the participants seated in the chairs lined up and the researcher in front of everyone, leading the reading and clarifying any doubts that came up in each meeting.

Analysis of results and statistics
The collected data were entered into Excel. Next, the SPSS Statistics software, version 24, was used. The level of significance was established at 5% and the confidence interval was 95%. From the Kolmogorov-Smirnov test, it was verified that the data did not follow the normal distribution. The knowledge test data were submitted to the Mann-Whitney test and the attitude data were analyzed using Pearson's Chi-square.

RESULTS
Participants were 56 patients in the preoperative period of bariatric surgery. Figure 1 illustrates the allocation of subjects in the study.
The frequency of women in the control group was 83.3% (25) and 96.7% (29) in the intervention group. The mean age was 38.77±9.18 years in the control group, with a variance of 19 to 63 years and a median of 37 years. In the intervention group, the mean age was 41.23±9.74 years, with a variance of 21 to 65 years and a median of 40.5 years. Regarding the education, there was a predominance of 9 to 11 years among participants in the CG (63.3%-19) and IG (53.3%- 16).
Tables 1 to 4 present information about knowledge, with a comparison of the correct answers of each group at each moment of the perioperative period and a description of the theoretical content of each question.
The only questions with a low proportion of correct answers were related to family support (in the CG -60.7%) and the same preparation time before surgery for all patients (42.9% of correct answers in both groups). However, in the second moment, all items had a frequency  of correct answers greater than 75% in the CG and IG, except in the question of preparation time, in which the CG remained with 42.9% of correct answers, compared to 75% of the IG (p=0.035) and questions about the importance of family support and the need to try conventional treatments to lose weight before choosing bariatric surgery, both with 71.4% correct answers (Table 1). Table 2 shows that questions about the benefits of walking and compression stockings for preventing thrombosis, and about lung improving with breathing exercises, were the only ones with correct answers above 70% in M0. After the intervention, all patients in the IG demonstrated suitable knowledge about the issues related to hospitalization and care in the hospital postoperative.   Regarding care at home in the postoperative period, in both groups, the correct answers were low (<70%) in questions about the cleaning of the surgical wound, vomiting and nausea, fluid intake, tooth brushing and the occurrence of psychological disorders. For these questions, there were no statistically significant differences between the participants of the CG in M2, while the IG showed an increase in the number of correct answers, with a frequency higher than 85% and statistically significant, except for the questions about regular vomiting and nausea (p=0.001) and water intake, even if not thirst (p=0.039) ( Table 3).
The questions about the late postoperative period with correct answers above 70%, in M0 were related to weight loss due to controlled eating and physical activity and effects of alcohol consumption. In the second assessment (M2), there was an improvement in knowledge for the IG in all questions, except concerning the discontinuing of medication, however, with statistical significance (p=0.002) ( Table 3).
In M0, the average of correct answers was 19.2 (±5.85) for the CG and 21.07 (± 5.82) for IG, with a p-value of 0.254 (similar knowledge in the baseline). In M2, the CG had an average of 19.5 (±6.17) and the IG of 31.1 (± 2.96), p=0.000. Besides, of the 35 questions about knowledge, the CG showed an increase in correct answers in 13 post-test questions, only one with statistical significance, while the IG increased up to 31 correct answers, with statistical significance in 17 of them.
The comparison of the attitude of both groups in the pre and post-test moments is shown in table 4.
In Table 4, it is possible to observe that in M0 and M2, patients showed a positive attitude to follow the care to change their lifestyle habits. Most study participants consider it important to follow-up care in the postoperative period to improve the quality of life and health status.
For the CG, correctly following postoperative care is associated with improved quality of life (M0=40%; M2=43.3%). For the IG, improving quality of life was more frequent in M0 (53.3%) and improving health status and comorbidities (53.3%) in M2.

DISCUSSION
Educational strategies applying technologies printed with organized illustrations and information before bariatric surgery can promote self-care attitudes. They represent the opportunity to solve doubts and help patients deal with their expectations concerning the surgical procedure and the experience of the postoperative period.
In the post-test, all participants demonstrated satisfactory knowledge about the main benefits of bariatric surgery. It is relevant to know the benefits of the surgical procedure, such as weight loss and improved metabolic parameters, to propose actions that avoid complications, promote self-care, and improve quality of life (7) . A qualitative study was carried out in Pennsylvania to identify the perceptions of postoperative patients about the guidance received by the multi-professional team, and showed that the participants consider relevant the information on types of surgery, their risks/benefits and weight loss (8) .
In this study, patients revealed that they consider the preoperative preparation time similar for all individuals, which can be observed in the total of correct answers, below 50%. In the post-test, only the intervention group achieved improvement in knowledge (42.9% to 75%, p=0.035) in this regard. Often, the required behavioral changes and preoperative assessments cause delays in the process, intensifying signs of dissatisfaction for people who are in a hurry to get it done (9) .
In the present study, a low percentage of correct answers (less than 50%) was found in M0 regarding the prevention of Deep Venous Thrombosis (DVT) and the need for care such as early walking and the use of compression stockings in the postoperative period. A study carried out in the United States identified that patients with less education are more likely to develop complications such as DVT (10) . As a prophylactic measure for venous thrombosis, patients can receive low molecular weight heparin and medium compression stockings above the knee in the night before surgery, with continuous use for 10 postoperative days; using compression devices during the surgical procedure; perform motor exercises or slow walks in the immediate postoperative period (11) .
Regarding the breathing exercises, both groups had correct answers greater than 90%, with no significant difference between the moments of the collection. Morbidly obese patients are at increased risk of hypoxemia in the postoperative period, which can cause a higher incidence of postoperative pulmonary complications, increase the length of hospital stay and reflect higher health costs (12) . As for the possible fall out of the stomach stitches and the need for reoperation, there was an improvement in knowledge (M2-M0) only among patients who had access to the booklet, with a p-value of 0.000 and 0.003, respectively. The detailed assessment of the surgical risks for each patient is important for the patient's informed decision-making regarding the surgical treatment of obesity, besides guiding the multidisciplinary team to the choice of the specific intervention that improves the results in the preparation and after surgery (13) .
In the United States, an intervention study using printed materials with 3D animations to guide 19 adults about the risks of bariatric surgery showed that the participants were able to infer key elements to prevent complications, such as properly chewing food and correctly follow the liquid diet to avoid surgical ruptures (14) .
During preoperative preparation, information related to nutrition should be highlighted, such as compliance with the diet, hydration, and food satisfaction. Sparkling drinks are also contraindicated, as they cause dilation (15) . The benefits of following nutritional guidelines are associated with reducing the incidence of slow weight loss, plateau effect, weight gain, dehydration, pain, discomfort, indigestion, vomiting and dumping syndrome. However, the ability to make changes in the diet depends on environmental factors (the house and kitchen assembly and the availability of easy access to buy food); financial (ability to afford the costs related to the acquisition of protein, vitamins, fresh fruits and vegetables); family and psychological support (16) .
In Israel, a randomized clinical trial with 128 candidates for bariatric surgery applied online educational intervention on pre-and post-surgery dietary guidelines; food supplement and nutritional strategies to maintain long-term weight loss. The intervention patients had a better performance in the knowledge test about nutritional aspects and lower scores of anxiety, compared to the control group (17) .
An issue that causes concern is the patients' belief about regular nausea and vomiting in the postoperative period. Bariatric surgery restricts the amount of food that an individual can consume (18) . Thus, if the patient does not respect the signs that the body shows it is full during meals, the probability of vomiting is greater.
It is known that the frequent vomiting, with immediate teeth brushing, can increase mineral loss due to the loss of calcium in the tooth enamel, leading to tooth hypersensitivity, which may have an impact on the patient's quality of life (19) . Despite the bad feeling due to the unpleasant taste in the mouth, it is recommended that patients wait 20 to 30 minutes to brush their teeth.
In the postoperative period, the patient may experience episodes of depression, shopping, drink and eating compulsion or other psychological disorders, therefore the importance of advising patients preoperatively about the occurrence of these events.
Both eating behavior and depression in the post-surgical period are associated with less weight loss (20) . In Portugal, a crosssectional study showed the association between weight gain after surgery and episodes of compulsive food intake, concerns about body image and depressive symptoms (21) , which warns of the need for professional support in the postoperative period.
In Germany, a randomized clinical trial was conducted with 117 patients to assess the effectiveness of psychoeducational intervention after bariatric surgery. The topics covered were: how to deal with binge eating, pinching, society and feelings, in addition to body image, perfectionism, self-esteem and self-nutrition. The results showed that the group that participated in the program for two years had better self-efficacy and reduced scores of depression severity (22) .
It is important to prepare the patient for physical and behavioral changes that may occur after surgery. In the postoperative period, changes in the taste and smell of the food are normal; an increase in the number of daily bowel movements with feces and gases with a strong-smelling odor; increased sweat and abrasions in areas where there is excess skin.
As fats are poorly absorbed, feces are more frequent and have a strong-smelling odor. Complaints such as cold intolerance, hair loss, fatigue and dry skin occur due to the decrease in the basal metabolic rate (23) . Hypometabolism is common during the first six months after bariatric surgery and these effects tend to decrease as weight loss stabilizes (24) .
As for the knowledge of one of the most common complications, which is the dumping syndrome, there was a difference between the groups, and the variation of correct answers was from 53.6% (M0) to 50% in the control group (p=1), and from 46.4% to 96.4% in the intervention group (p=0.000). This syndrome is characterized by vasomotor and gastrointestinal symptoms caused by rapid gastric emptying after eating or the sudden exposure of the small intestine to nutrients (25)(26) .
In this study, both in M0 and M2, a positive attitude was observed given the need for obedience to care in the postoperative period to achieve positive and lasting results. The absence of variation in the verification of the candidates' attitude is a relevant finding and demonstrates that the participants consider it necessary to follow up with the multi-professional team.
This reveals that the participants know the theme addressed, arising from the guidelines received at the institution and from living with other postoperative patients during monthly meetings. More and more, the population has been searching for information about bariatric surgery on the internet and with friends, to understand more about the procedure and the necessary care (6) .
Educating people should not be interpreted as a way of adding knowledge and values, but as an action centered on the problematization of daily life, on individual, family and social groups experience, and respect for cultural differences (27) . Making the patient active and engaged in the care process through health education, will enable greater individual interest in the search for knowledge about the body function and the diseases to which it is subject, reducing the morbidity and mortality rates and improving the quality of care life (28) .

Study limitations
The study limitation refers to its conduction with participants accompanied by the SUS bariatric surgery program, which represents a population with a low level of education. Thus, the results may differ from the reality of patients in the preoperative period of private health institutions, who have greater purchasing power and higher education.