Eli Maria Pazzianotto-Forti

Analysis of the prevalence of atelectasis in patients undergoing bariatric surgery

BACKGROUND AND OBJECTIVE To observe the prevalence of atelectasis in patients undergoing bariatric surgery and the influence of the body mass index (BMI), gender and age on the prevalence of atelectasis. METHOD Retrospective study of 407 patients and reports on chest X-rays carried out before and after bariatric surgery over a period of 14 months. Only patients who underwent bariatric surgery by laparotomy were included. RESULTS There was an overall prevalence of 37.84% of atelectasis, with the highest prevalence in the lung bases and with greater prevalence in women (RR=1.48). There was a ratio of 30% for the influence of age for individuals under the age of 36, and of 45% for those older than 36 (RR=0.68). There was no significant influence of BMI on the prevalence of atelectasis. CONCLUSION The prevalence of atelectasis in bariatric surgery is 37% and the main risk factors are being female and aged over 36 years.

Use of positive pressure in the bariatric surgery and effects on pulmonary function and prevalence of atelectasis: randomized and blinded clinical trial

Background In surgical procedures, obesity is a risk factor for the onset of intra and postoperative respiratory complications. Aim Determine what moment of application of positive pressure brings better benefits on lung function, incidence of atelectasis and diaphragmatic excursion, in the preoperative, intraoperative or immediate postoperative period. Method Randomized, controlled, blinded study, conducted in a hospital and included subjects with BMI between 40 and 55 kg/m2, 25 and 55 years, underwent bariatric surgery by laparotomy. They were underwent preoperative and postoperative evaluations. They were allocated into four different groups: 1) Gpre: treated with positive pressure in the BiPAP mode (Bi-Level Positive Airway Pressure) before surgery for one hour; 2) Gpos: BIPAP after surgery for one hour; 3) Gintra: PEEP (Positive End Expiratory Pressure) at 10 cmH2O during the surgery; 4) Gcontrol: only conventional respiratory physiotherapy. The evaluation consisted of anthropometric data, pulmonary function tests and chest radiography. Results Were allocated 40 patients, 10 in each group. There were significant differences for the expiratory reserve volume and percentage of the predicted expiratory reserve volume, in which the groups that received treatment showed a smaller loss in expiratory reserve volume from the preoperative to postoperative stages. The postoperative radiographic analysis showed a 25% prevalence of atelectasis for Gcontrol, 11.1% for Gintra, 10% for Gpre, and 0% for Gpos. There was no significant difference in diaphragmatic mobility amongst the groups. Conclusion The optimal time of application of positive pressure is in the immediate postoperative period, immediately after extubation, because it reduces the incidence of atelectasis and there is reduction of loss of expiratory reserve volume.

Comportamento da força muscular respiratória de obesas mórbidas por diferentes equações preditivas

BACKGROUND: Studies on the behavior of respiratory muscle strength (RMS) in morbidly obese patients have found conflicting results. OBJECTIVES: To evaluate RMS in morbidly obese women and to compare the results by using different predictive equations. METHOD: This is a cross-sectional study that recruited 30 morbidly obese women and a control group of 30 normal-weight women. The subjects underwent anthropometric and maximal respiratory pressure measurement. Visual inspection of the Bland-Altman plots was performed to evaluate the correlation between the different equations, with a p value lower than 0.05 considered as statistically significant. RESULTS: The obese women showed a significant increase in maximal inspiratory pressure (MIP) values (-87.83±21.40 cmH2O) compared with normal-weight women (-72±15.23 cmH2O) and a significant reduction of MIP (-87.83±21.40 cmH2O) according to the values predicted by the EHarik equation (-130.71±11.98 cmH2O). Regarding the obtained maximal expiratory pressure (MEP), there were no between-group differences (p>0.05), and no agreeement was observed between obtained and predicted values of MEP and the ENeder and ECosta equations. CONCLUSIONS: Inspiratory muscle strength was greater in the morbidly obese subjects. The most appropriate equation for calculating the predicted MIP values for the morbidly obese seems to be Harik-Khan equation. There seem to be similarities between the respiratory muscle strength behavior of morbidly obese and normal-weight women, however, these findings are still inconclusive.

Lung age in women with morbid obesity

OBJECTIVE To investigate the influence of morbid obesity on the lung age in women and to correlate with body mass, body mass index (BMI), and ventilatory variables. METHODS This was a cross-sectional study with 72 morbidly obese women and a control group consisting of 37 normal weight women. The subjects performed a pulmonary function test to determine lung age, and the results were correlated to anthropometric variables and lung volumes. RESULTS The morbidly obese group had significantly higher lung age (50.1±6.8 years) than the control group (38.8±11.4 years). There was no difference in chronological age between groups. There was a significant positive correlation among chronological age, body mass, BMI, and lung age (r=0.3647, 0.4182, and 0.3743, respectively). There was a negative correlation among forced vital capacity (FVC), forced expiratory volume in one second (FEV1), FEV1/FVC ratio, expiratory reserve volume (ERV), and lung age (r=-0.7565, -0.8769, --0.2723, and -0.2417, respectively). CONCLUSION Lung age is increased in morbidly obese women and is associated with increased body mass and BMI.

Application of positive airway pressure in restoring pulmonary function and thoracic mobility in the postoperative period of bariatric surgery: a randomized clinical trial

Objective: To evaluate whether the application of bilevel positive airway pressure in the postoperative period of bariatric surgery might be more effective in restoring lung volume and capacity and thoracic mobility than the separate application of expiratory and inspiratory positive pressure. Method: Sixty morbidly obese adult subjects who were hospitalized for bariatric surgery and met the predefined inclusion criteria were evaluated. The pulmonary function and thoracic mobility were preoperatively assessed by spirometry and cirtometry and reevaluated on the 1st postoperative day. After preoperative evaluation, the subjects were randomized and allocated into groups: EPAP Group (n=20), IPPB Group (n=20) and BIPAP Group (n=20), then received the corresponding intervention: positive expiratory pressure (EPAP), inspiratory positive pressure breathing (IPPB) or bilevel inspiratory positive airway pressure (BIPAP), in 6 sets of 15 breaths or 30 minutes twice a day in the immediate postoperative period and on the 1st postoperative day, in addition to conventional physical therapy. Results: There was a significant postoperative reduction in spirometric variables (p<0.05), regardless of the technique used, with no significant difference among the techniques (p>0.05). Thoracic mobility was preserved only in group BIPAP (p>0.05), but no significant difference was found in the comparison among groups (p>0.05). Conclusion: The application of positive pressure does not seem to be effective in restoring lung function after bariatric surgery, but the use of bilevel positive pressure can preserve thoracic mobility, although this technique was not superior to the other techniques.

Fisioterapia respiratória associada à pressão positiva nas vias aéreas na evolução pós-operatória da cirurgia bariátrica

Analisar volume corrente (VC), volume minuto (VM) e frequencia respiratoria (FR) de obesas morbidas no pos-operatorio de cirurgia bariatrica (CB), apos a fisioterapia respiratoria convencional (FRC) associada ou nao a pressao positiva continua nas vias aereas (CPAP) no pre-operatorio. Foram estudadas 36 mulheres, com idade de 40,1±8,41 anos, que seriam submetidas a CB por laparotomia e que realizaram FRC (exercicios respiratorios diafragmaticos, de inspiracoes profundas, fracionadas e associados a movimentos de membros superiores, 1 serie de 10 repeticoes de cada exercicio) por 30 dias antes da cirurgia. Apos internacao, 18 delas foram submetidas a 20 minutos de CPAP, 1 hora antes da inducao anestesica e compuseram o grupo FRC+CPAP. As outras 18 nao receberam o CPAP e compuseram o grupo FRC. Foram avaliados VM, VC e FR por meio do ventilometro, no momento da internacao e 24 horas apos a realizacao da cirurgia. Constatou-se que as medidas de VC, VM e FR nao apresentaram significância estatistica quando comparados os resultados do pre e pos-operatorio em ambos os grupos, bem como quando comparados os dois grupos entre si tanto no pre como no pos-operatorio. Os resultados sugerem que a tanto a aplicacao da FRC como a aplicacao da FRC+CPAP no periodo pre-operatorio contribui para a manutencao das variaveis respiratorias no pos-operatorio. A aplicacao do CPAP antes da inducao anestesica nao promoveu beneficios adicionais no pos-operatorio de CB no que se refere aos volumes pulmonares.

Impact of pain in overweight to morbidly obese women: preliminary findings of a cross-sectional study

OBJECTIVES To evaluate the effect of body mass index (BMI) on the prevalence, intensity and interference of pain in women, and how it affects quality of life and level of physical activity; and to determine independent predictors of pain intensity. DESIGN Cross-sectional observational study. SETTINGS Obesity treatment clinic, community and university laboratory. PARTICIPANTS Seventy-three of 133 women aged 25-75 years reported the presence of pain for at least 2 weeks and were categorised according to BMI (normal weight, overweight, obese or morbidly obese). MAIN OUTCOME MEASURES BMI and questionnaires [McGill Pain Questionnaire (MPQ), Brief Pain Inventory (BPI), Short-Form Health Survey-36 (SF-36) and Baecke Physical Activity Questionnaire]. RESULTS Pain intensity was 3 and 4.5 times higher in the MPQ and BPI, respectively, in morbidly obese women compared with women of normal weight. Morbidly obese women had 10.7 times higher pain interference and lower scores on the SF-36 domains of physical function and role function-physical compared with women of normal weight. Obese and morbidly obese women had less pain relief from treatment. Regression analysis showed that high BMI and low level of physical activity contributed to the intensity of pain, and these variables explained 16% of the variance of pain intensity. CONCLUSIONS This study found that the prevalence and intensity of pain are greater in morbidly obese women than women of normal weight, and pain is negatively associated with physical activity. The causal inter-relationships between pain, obesity and physical activity are complex and require further study.

AIRWAY POSITIVE PRESSURE VS. EXERCISES WITH INSPIRATORY LOADING FOCUSED ON PULMONARY AND RESPIRATORY MUSCULAR FUNCTIONS IN THE POSTOPERATIVE PERIOD OF BARIATRIC SURGERY

ABSTRACT Background: Bariatric surgery can trigger postoperative pulmonary complications due to factors inherent to the procedure, mainly due to diaphragmatic dysfunction. Aim: To evaluate and compare the effects of two levels of positive pressure and exercises with inspiratory load on lung function, inspiratory muscle strength and respiratory muscle resistance, and the prevalence of atelectasis after gastroplasty. Methods: Clinical, randomized and blind trial, with subjects submitted to bariatric surgery, allocated to two groups: positive pressure group, who received positive pressure at two levels during one hour and conventional respiratory physiotherapy and inspiratory load group, who performed exercises with load linear inspiratory pressure, six sets of 15 repetitions, in addition to conventional respiratory physiotherapy, both of which were applied twice in the immediate postoperative period and three times a day on the first postoperative day. Spirometry was performed for pulmonary function analysis, nasal inspiratory pressure for inspiratory muscle strength and incremental test of respiratory muscle resistance for sustained maximal inspiratory pressure, both preoperatively and on hospital discharge on the second postoperative day. Results: There was no significant difference (p> 0.05) in the expiratory reserve volume and in the tidal volume in the pre and postoperative periods when compared intra and intergroup. There was no significant difference (p>0.05) in the nasal inspiratory pressure and the maximal inspiratory pressure maintained in the inspiratory load group in the intragroup evaluation, but with a significant difference (p<0.05) compared to the positive pressure group. The prevalence of atelectasis was 5% in both groups with no significant difference (p>0.05) between them. Conclusion: Both groups, associated with conventional respiratory physiotherapy, preserved expiratory reserve volume and tidal volume and had a low atelectasis rate. The inspiratory loading group still maintained inspiratory muscle strength and resistance of respiratory muscles.

Atelectasias em pacientes submetidos à cirurgia bariátrica sem qualquer alteração pulmonar prévia: comentários do estudo de prevalência

Obesity is a risk factor intrinsic to the development of areas of atelectasis, especially when the patient undergoes to general anesthesia and, therefore, some groups of studies has been dedicated to studying such subject. The recently published letter to the editor comments on and points out some aspects regarding the article on the prevalence of atelectasis in the obese Grade III submitted to bariatric surgery. In response, the clinical relevance of this study is that there are no studies in the literature consulted to date that have observed the prevalence of atelectasis in the postoperative period of bariatric surgery since they may cause respiratory failure in these patients. Considering this prevalence, it is possible to study effective prevention and treatment measures to minimize postoperative complications. Thus, firstly, in fact, the retrospective analysis is subject to bias, but the service in which the study was carried out follows strict protocols instituted for years regarding preoperative preparation, hospitalization, medications, anesthetic and surgical staff, anesthesia and surgery techniques, recovery time in the postoperative period and complementary exams. In addition the data collection time was only 14 months and thus, these facts can minimize the biases of a retrospective study. The fact that a study with only patients with previous pulmonary alterations is against the initial proposal of the research, which aims to observe the development of atelectasis in patients without any pulmonary alterations or respiratory symptoms so that we can actually reinforce the assumption that obesity alone is a risk factor for the development of respiratory complications and such complications can be triggered by the emergence of atelectasis areas. The research group also investigated solutions to minimize the prevalence of atelectasis in these patients by applying positive pressure at different times of hospitalization and, in corroboration with the cited author, we also identified that the best time is soon after extubation, because it reduces the prevalence of atelectasis and has less loss of expiratory reserve volume. Second, regarding the predominance of the female gender, it is common to observe a higher prevalence of women in studies of obesity as already demonstrated in the study conducted by Ogden et al., in which a higher prevalence of obesity was observed in women. This fact has several explanations, ranging from the different hormonal factors involved in the gender to the greater outpatient demand for women who seem to be more concerned about health. As a result, it becomes more difficult to homogenize the sample with respect to gender. However, with the Chi-square test used in the study to analyze the association between gender and prevalence of atelectasis, it is possible to isolate the discrepancy effects of the sample. Thirdly, in fact, physiotherapy has been shown to be of extreme relevance in the treatment of patients in the pre and postoperative period of abdominal surgeries, as demonstrated in a literature review performed by Lawrence et al., in which it was concluded that respiratory physiotherapy with reexpansive techniques has proven benefits in reducing postoperative complications in abdominal surgeries. Moreover, since then, several other studies have been emerging to prove even more this finding. In view of the vast evidence of the benefits of physical therapy in these cases, the hospital conducting the study, as well as several others, already includes respiratory physiotherapy in the routine of these patients when they are hospitalized. However, the high prevalence of atelectasis in these patients must be observed, and the researchers should direct attention to new treatment techniques in order to avoid them. Finally, the authors also agree that more research is encouraged in this area to evaluate the respiratory complications related to abdominal surgeries and their possible risk factors as well as to perform the best prevention or treatment.

Influence of body mass index and age on the lung function of obese women

Introducao: A obesidade e o envelhecimento podem promover alteracoes na funcao pulmonar. Objetivo: avaliar se a massa corporal, o indice de massa corporal (IMC) e a idade tem influencia sobre a capacidade vital (CV) e o volume expiratorio forcado no primeiro segundo (VEF1) em mulheres. Metodos: Participaram do estudo 81 mulheres, com idade entre 30 e 75 anos, obesas e obesas morbidas, nao fumantes, sedentarias e sem alteracoes pulmonares cronicas. Foram realizadas anamnese, avaliacao antropometrica e espirometrica. A analise estatistica dos dados foi realizada atraves dos testes de correlacao de Pearson e Spearman, adotando um nivel de significância de 5%. Resultados: Pode-se observar que a idade apresentou correlacoes significativas e negativas com a CV e seus componentes: volume de reserva inspiratorio (VRI), volume de reserva expiratorio (VRE) e volume corrente (VC) e tambem com o VEF1. Houve correlacao significativa e positiva da massa corporal com a CV e com o VRI, e correlacao significativa e negativa entre o IMC e o VRE. Conclusao: Com o passar dos anos ocorre declinio da funcao pulmonar. A massa corporal parece exercer maior influencia no VRI, ao passo que com o aumento do IMC ocorre declinio do VRE.