title: Stepwise rising CO2 insufflation as an ischemic preconditioning method.
abstract: BACKGROUND
  The pneumoperitoneum (Pp) is associated with ischemia and reperfusion (I/R) injury and oxidative stress. Various ischemic-preconditioning (IP) methods were used to reduce ischemic injury in intra-abdominal organs. In this experimental, randomized, controlled trial with a blind assessment of the outcome, we evaluated the effects of a new IP method, stepwise rising CO(2) insufflation, on oxidative stress and inflammatory cytokine response.
  
  
  METHODS
  Twenty-one rats were divided into three groups. Rats in the control group were subjected to general anesthesia for only 60 minutes. The stepwise group was subjected to 5 mm Hg for 10 minutes, 10 mm Hg for 10 minutes, and 15 mm Hg of CO(2) insufflation for 60 minutes without deflation. In the Pp15 group, the pressure of CO(2) insufflation was fixed at 15 mm Hg for 60 minutes without deflation. Liver and blood samples were examined to determine malondialdehyde (MDA), the antioxidant, superoxide dismutase (SOD), and inflammatory cytokine (tumor necrosis factor-alpha [TNF-alpha], interleukin-6 [IL-6]) levels. Histopathologic scores of liver tissue were examined in all groups.
  
  
  RESULTS
  The highest plasma and liver MDA, TNF-alpha, and IL-6 values were in the Pp15 group, followed by the stepwise and control groups. However, plasma and liver SOD levels determined in the control group were significantly higher, compared to stepwise and Pp15 groups. The lowest plasma and liver levels of SOD were in the Pp15 group, followed by the stepwise and control groups. Significantly higher histopathologic scores were found in the Pp15 group, followed by the stepwise and control groups, as well as MDA and inflammatory cytokine (TNF-alpha, IL-6) levels.
  
  
  CONCLUSIONS
  We concluded that the stepwise rising CO(2) insufflation method may be an alternative IP method that may lead to a reduction in I/R injury.
authors.affiliation: Department of General Surgery, Afyonkarahisar Kocatepe University, School of Medicine, Afyonkarahisar, Turkey.
authors.forename: Dursun A
authors.initials: DA
authors.lastname: Sahin
authors.forename: Berna
authors.initials: B
authors.lastname: Haliloglu
authors.forename: Figen Kir
authors.initials: FK
authors.lastname: Sahin
authors.forename: Gokhan
authors.initials: G
authors.lastname: Akbulut
authors.forename: Huseyin
authors.initials: H
authors.lastname: Fidan
authors.forename: Gulengul
authors.initials: G
authors.lastname: Koken
authors.forename: Sadik
authors.initials: S
authors.lastname: Buyukbas
authors.forename: Fatma
authors.initials: F
authors.lastname: Aktepe
authors.forename: Yuksel
authors.initials: Y
authors.lastname: Arikan
authors.forename: Osman Nuri
authors.initials: ON
authors.lastname: Dilek
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D002245:Carbon Dioxide; D004797:Enzyme-Linked Immunosorbent Assay; D007327:Insufflation / Q000009:adverse effects* / Q000379:methods; D015850:Interleukin-6 / Q000378:metabolism; D019194:Ischemic Preconditioning / Q000379:methods*; D010535:Laparoscopy / Q000009:adverse effects* / Q000379:methods; D008099:Liver / Q000098:blood supply* / Q000293:injuries / Q000378:metabolism; D008315:Malondialdehyde / Q000378:metabolism; D018384:Oxidative Stress; D011028:Pneumoperitoneum, Artificial / Q000009:adverse effects; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D018709:Statistics, Nonparametric; D013482:Superoxide Dismutase / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D015850:Interleukin-6; D014409:Tumor Necrosis Factor-alpha; D002245:Carbon Dioxide; D008315:Malondialdehyde; D013482:Superoxide Dismutase