title: Respiratory pressures and expiratory peak flow rate of patients undergoing coronary artery bypass graft surgery.
abstract: BACKGROUND
  To evaluate clinical and laboratorial parameters that predict decreased respiratory function in patients subjected to coronary artery bypass graft surgery (CABG).
  
  
  METHODS
  This was a prospective study evaluating 61 patients subjected to CABG with cardiopulmonary bypass, median sternotomy, and under mechanical ventilation for up to 24 h. One day before surgery, clinical information was recorded. Maximal inspiratory (MIP) and expiratory (MEP) pressures, and expiratory peak flow rate (EPFR) values were assessed 1 day before surgery and on the fifth postoperative day. Student's t test, 2-way ANOVA, Pearson's linear correlation, and logistic regression were used for statistical analysis.
  
  
  RESULTS
  Patients were 63±10 years old, 67% males. Arterial hypertension was found in 75.4% of the patients, diabetes in 31.2%, dyslipidemia in 63.9%, tabagism in 25%, and chronic obstructive pulmonary disease (COPD) in 16.4%. Previous myocardial infarction was found in 67%. Preoperative hemoglobin levels were 12.8±1.71 g/dL. Older individuals had lower preoperative MEP and EPFR values. Preoperatively, positive association was found between hemoglobin levels and maximal respiratory pressures and EPFR values. Patients with both class III angina and COPD presented higher reductions in pulmonary pressures between the preoperative period and the 5th postoperative day.
  
  
  CONCLUSIONS
  Older age and low hemoglobin levels are associated with preoperative low maximal respiratory pressures and EPFR. The combination of severe angina and COPD results in higher postoperative reduction of maximal respiratory pressures for patients who underwent CABG.
authors.affiliation: Department of Internal Medicine, Botucatu Medical School, Sao Paulo State University, UNESP, Sao Paulo, Brazil.
authors.forename: Camila
authors.initials: C
authors.lastname: Gimenes
authors.forename: Irma
authors.initials: I
authors.lastname: de Godoy
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Padovani
authors.forename: Rodrigo
authors.initials: R
authors.lastname: Gimenes
authors.forename: Marina Politi
authors.initials: MP
authors.lastname: Okoshi
authors.forename: Katashi
authors.initials: K
authors.lastname: Okoshi
mesh_terms: D000367:Age Factors; D000368:Aged; D000704:Analysis of Variance; D001026:Coronary Artery Bypass; D003404:Creatinine / Q000097:blood; D005260:Female; D006400:Hematocrit; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007320:Inspiratory Capacity / Q000502:physiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D010366:Peak Expiratory Flow Rate / Q000502:physiology*; D011446:Prospective Studies; D012123:Pulmonary Ventilation / Q000502:physiology*; D014508:Urea / Q000097:blood
chemical_list: D006454:Hemoglobins; D014508:Urea; D003404:Creatinine