title: Effects of different levels of end-expiratory pressure on hemodynamic, respiratory mechanics and systemic stress response during laparoscopic cholecystectomy.
abstract: OBJECTIVE
  General anesthesia causes reduction of functional residual capacity. And this decrease can lead to atelectasis and intrapulmonary shunting in the lung. In this study we want to evaluate the effects of 5 and 10cmH2O PEEP levels on gas exchange, hemodynamic, respiratory mechanics and systemic stress response in laparoscopic cholecystectomy.
  
  
  METHODS
  American Society of Anesthesiologist I-II physical status 43 patients scheduled for laparoscopic cholecystectomy were randomly selected to receive external PEEP of 5cmH2O (PEEP 5 group) or 10cmH2O PEEP (PEEP 10 group) during pneumoperitoneum. Basal hemodynamic parameters were recorded, and arterial blood gases (ABG) and blood sampling were done for cortisol, insulin and glucose level estimations to assess the systemic stress response before induction of anesthesia. Thirty minutes after the pneumoperitoneum, the respiratory and hemodynamic parameters were recorded again and ABG and sampling for cortisol, insulin, and glucose levels were repeated. Lastly hemodynamic parameters were recorded; ABG analysis and sampling for stress response levels were taken after 60minutes from extubation.
  
  
  RESULTS
  There were no statistical differences between the two groups about hemodynamic and respiratory parameters except mean airway pressure (Pmean). Pmean, compliance and PaO2; pH values were higher in 'PEEP 10 group'. Also, PaCO2values were lower in 'PEEP 10 group'. No differences were observed between insulin and lactic acid levels in the two groups. But postoperative cortisol level was significantly lower in 'PEEP 10 group'.
  
  
  CONCLUSIONS
  Ventilation with 10cmH2O PEEP increases compliance and oxygenation, does not cause hemodynamic and respiratory complications and reduces the postoperative stress response.
authors.affiliation: Ministery of Health Haseki Training and Research Hospital, Department of Anaesthesiology and Reanimation, Istanbul, Turkey. Electronic address: senoznur@gmail.com.
authors.forename: Oznur
authors.initials: O
authors.lastname: Sen
authors.affiliation: Ministery of Health Haseki Training and Research Hospital, Department of Biochemistry Department, Istanbul, Turkey.
authors.forename: Yasemin
authors.initials: Y
authors.lastname: Erdogan Doventas
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D017081:Cholecystectomy, Laparoscopic; D004562:Electrocardiography; D005260:Female; D006339:Heart Rate / Q000502:physiology; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011175:Positive-Pressure Respiration; D011446:Prospective Studies; D015656:Respiratory Mechanics / Q000502:physiology*; D013312:Stress, Physiological / Q000502:physiology*; D055815:Young Adult
keywords: Hemodinâmica; Hemodynamic; Mecânica respiratória e resposta ao estresse; PEEP; Respiratory mechanics and stress response