title: Comparison of two ventilatory strategies in elderly patients undergoing major abdominal surgery.
abstract: BACKGROUND
  'Open lung' ventilation is commonly used in patients with acute lung injury and has been shown to improve intraoperative oxygenation in obese patients undergoing laparoscopic surgery. The feasibility of an 'open lung' ventilatory strategy in elderly patients under general anaesthesia has not previously been assessed.
  
  
  METHODS
  'Open lung' ventilation (recruitment manoeuvres, tidal volume 6 ml kg(-1) predicted body weight, and 12 cm H(2)O PEEP) (RM group) was compared with conventional ventilation (no recruitment manoeuvres, tidal volume 10 ml kg(-1) predicted body weight, and zero end-expiratory pressure) in elderly patients (>65 yr) undergoing major open abdominal surgery with regard to oxygenation, respiratory system mechanics, and haemodynamic stability. We also monitored the serum levels of the interleukins (IL)-6 and IL-8 before and after surgery to determine whether the systemic inflammatory response to surgery depends on the ventilatory strategy used.
  
  
  RESULTS
  Twenty patients were included in each group. The RM group tolerated open lung ventilation without significant haemodynamic instability. Intraoperative Pa(o(2)) improved in the RM group (P<0.01) and deteriorated in controls (P=0.01), but postoperative Pa(o(2)) was similar in both groups. The RM group had improved breathing mechanics as evidenced by increased dynamic compliance (36%) and decreased airway resistance (21%). Both IL-6 and IL-8 significantly increased after surgery, but the magnitude of increase did not differ between the groups.
  
  
  CONCLUSIONS
  A lung recruitment strategy in elderly patients is well tolerated and improves intraoperative oxygenation and lung mechanics during laparotomy.
authors.affiliation: Department of Anesthesiology and Anesthesia Clinical Research Unit, College of Medicine, Mayo Clinic, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: T N
authors.initials: TN
authors.lastname: Weingarten
authors.forename: F X
authors.initials: FX
authors.lastname: Whalen
authors.forename: D O
authors.initials: DO
authors.lastname: Warner
authors.forename: O
authors.initials: O
authors.lastname: Gajic
authors.forename: G J
authors.initials: GJ
authors.lastname: Schears
authors.forename: M R
authors.initials: MR
authors.lastname: Snyder
authors.forename: D R
authors.initials: DR
authors.lastname: Schroeder
authors.forename: J
authors.initials: J
authors.lastname: Sprung
mesh_terms: D000005:Abdomen / Q000601:surgery*; D000368:Aged; D000369:Aged, 80 and over; D000403:Airway Resistance; D000768:Anesthesia, General / Q000379:methods*; D002245:Carbon Dioxide / Q000097:blood; D005260:Female; D006439:Hemodynamics; D006801:Humans; D015850:Interleukin-6 / Q000097:blood; D016209:Interleukin-8 / Q000097:blood; D008297:Male; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011175:Positive-Pressure Respiration / Q000379:methods; D011183:Postoperative Complications; D012121:Respiration, Artificial / Q000379:methods*
chemical_list: D015850:Interleukin-6; D016209:Interleukin-8; D002245:Carbon Dioxide; D010100:Oxygen