Comparison of Oxidative Stress Changes in Different Ventilation Strategies During Gynecologic Laparoscopic Surgery
Condition: Reperfusion Injury; Oxidative Stress
MeSH terms: Reperfusion Injury
Study type: Interventional

Summary: 
      Ischemia-reperfusion injury resulted from pneumoperitoneum during laparoscopic surgery have
      been reported in some literatures. There are no studies investigating the time course of
      changes in oxidative stress markers in volume-controlled ventilation (VCV) and
      pressure-controlled ventilation (PCV) modes. The aim of this study is to compare the
      alterations in oxidative stress in two different ventilation strategies during gynecologic
      laparoscopic surgery.

      Methods:

      Fifty-two patients of ASA physical status I or II were randomly assigned to receive either
      VCV or PCV during laparoscopic gynecologic surgery. Blood gas analysis and ventilation
      variables were recorded 1 minute before (T1) and 1 hour after (T2) pneumoperitoneum. Blood
      samples for malondialdehyde (MDA) measurement were collected at seven points: 1 minute before
      (T1) and 1 hour after (T2) pneumoperitoneum; 30 minutes, 60 minutes, 90 minutes, and 120
      minutes after deflation (T3~T6); and 24 hours after deflation (T7).
    

Detailed description: 
      Pneumoperitoneum during laparoscopic procedures greatly impairs splanchnic blood flow due to
      compression. Increased intra-abdominal pressure may elevate the diaphragm, increase
      intra-thoracic pressure, reduce functional residual capacity, and thus lead to atelectasis.
      In a collapsed lung, blood flow is decreased and reperfusion injury may subsequently occur
      during re-expansion of the lung. This ischemia-reperfusion injury results from the formation
      of reactive oxygen species (ROS), which are highly reactive intermediates of the oxygen
      metabolism. When there is an imbalance between ROS generation and removal by antioxidative
      mechanisms, oxidative stress occurs and eventually causes cellular and organ damage.
      Oxidative stress mediates tissue injury and may represent an important link between
      laparoscopy and clinical side effects. Malondialdehyde (MDA) is considered the most reliable
      marker of oxidative stress in the clinical setting. It is a breakdown product of lipid
      peroxidation in tissues. An elevated concentration of MDA reflects the level of lipid
      peroxidation.

      Although there is abundant data comparing the effects of VCV and PCV during laparoscopic
      surgery, the time course of changes in oxidative stress in these two modes has not been
      elucidated. Therefore, the aim of this study was to compare the alterations of oxidative
      stress in two different ventilation modes, VCV and PCV, during gynecologic laparoscopic
      surgery. To this end, the investigators established a prospective randomized clinical study
      and measured the plasma levels of a lipid peroxidation marker at different stages.

      Fifty-two patients of ASA physical status I or II were randomly assigned to receive either
      VCV or PCV during laparoscopic gynecologic surgery. During the operation, blood gas analysis
      and ventilation variables were recorded 1 minute before (T1) and 1 hour after (T2) the
      establishment of CO2 pneumoperitoneum in both groups. Blood samples for MDA measurement were
      collected at seven points: 1 minute before (T1) and 1 hour after (T2) pneumoperitoneum; at
      intervals of 30 minutes for 2 hours after the deflation of CO2 (T3~T6); and 24 hours after
      the deflation of CO2 (T7). The samples were immediately centrifuged (1000g, 10 minutes) and
      the supernatants were stored at -800C until further analysis, which took place within 1 week.
      The investigators assessed the quality of recovery from anesthesia using a nine-item quality
      of recovery score (QoR Score) before operation and 24 hours after the deflation of CO2.
    

Intervention name(s): Volume-controlled ventilation; Pressure-controlled ventilation
Intervention type(s): Procedure; Procedure
Intervention description(s): a tidal volume of 8 ml/kg; a peak airway pressure to maintain a tidal volume of 8 ml/kg
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Prevention
Keywords: Pressure-controlled ventilation; Volume-controlled ventilation; Laparoscopy; Oxidative stress