title: Estimation of lung vital capacity before and after coronary artery bypass grafting surgery: a comparison of incentive spirometer and ventilometry.
abstract: BACKGROUND
  Measurement of vital capacity (VC) by spirometry is the most widely used technique for lung function evaluation, however, this form of assessment is costly and further investigation of other reliable methods at lower cost is necessary.
  
  
  OBJECTIVE
  To analyze the correlation between direct vital capacity measured with ventilometer and with incentive inspirometer in patients in pre and post cardiac surgery.
  
  
  METHODS
  Cross-sectional comparative study with patients undergoing cardiac surgery. Respiratory parameters were evaluated through the measurement of VC performed by ventilometer and inspirometer. To analyze data normality the Kolmogorov-Smirnov test was applied, for correlation the Pearson correlation coefficient was used and for comparison of variables in pre and post operative period Student's t test was adopted. We established a level of ignificance of 5%. Data was presented as an average, standard deviation and relative frequency when needed. The significance level was set at 5%.
  
  
  RESULTS
  We studied 52 patients undergoing cardiac surgery, 20 patients in preoperative with VC-ventilometer: 32.95 ± 11.4 ml/kg and VC-inspirometer: 28.9 ± 11 ml/Kg, r = 0.7 p < 0.001. In the post operatory, 32 patients were evaluated with VC-ventilometer: 28.27 ± 12.48 ml/kg and VC-inspirometer: 26.98 ± 11 ml/Kg, r = 0.95 p < 0.001. Presenting a very high correlation between the evaluation forms studied.
  
  
  CONCLUSIONS
  There was a high correlation between DVC measures with ventilometer and incentive spirometer in pre and post CABG surgery. Despite this, arises the necessity of further studies to evaluate the repercussion of this method in lowering costs at hospitals.
authors.affiliation: Faculdade Social, Salvador, Bahia, Brazil.
authors.forename: Areli Cunha
authors.initials: AC
authors.lastname: Pinheiro
authors.forename: Michelli Christina Magalhães
authors.initials: MC
authors.lastname: Novais
authors.forename: Mansueto Gomes
authors.initials: MG
authors.lastname: Neto
authors.forename: Marcus Vinicius Herbst
authors.initials: MV
authors.lastname: Rodrigues
authors.forename: Erenaldo
authors.initials: E
authors.lastname: de Souza Rodrigues
authors.forename: Roque
authors.initials: R
authors.lastname: Aras
authors.forename: Vitor Oliveira
authors.initials: VO
authors.lastname: Carvalho
mesh_terms: D001026:Coronary Artery Bypass; D003324:Coronary Artery Disease / Q000503:physiopathology / Q000601:surgery*; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D057234:Preoperative Period; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013147:Spirometry / Q000379:methods*; D014797:Vital Capacity / Q000502:physiology*