The Effects Of Inverse Ratio Ventilation On Cardiopulmonary Function In Obese Patients Undergoing Gynecologic Laparoscopy

Objective:To study volume-controlled inverse ratio ventilation (IRV) with I:E ratio2:1as against volume-controlled ventilation (Control group) with I:E ratio1:2in the obese patients undergoing gynecologic laparoscopy.Materials and Methods:Sixty obese patients undergoing gynecologic laparoscopy were randomly divided into IRV group and control group. The IRV group were ventilated with a tidal volume(Vt)8mL/kg,respiratory rate12breaths/min,I:E2:l;in the control group with I:E1:2.Respiratory frequency and tidal volume (Vt) were kept constant in both modes. Arterial blood was collected respectively to analyze blood gas at2min before pneumoperitoneum (T1) and60min after pneumoperitoneum(T2),airway pressure, hemodynamic parameters and respiratory mechanics were monitored and oxygenation index (OI) was calculated. Concentrations of TNF-α, IL-6and IL-8in bronchoalveolar lavage fluid (BALF) were measured. Results:IRV significantly increased partial pressure of O2in the arterial blood (PaO2), Pmean and oxygenation index (OI), dynamic compliance of lung with concomitant significant decrease in Ppeak compared to conventional ventilation with I:E ratio of1:2. There were no statistical differences between the two groups regarding the hemodynamic parameters and partial pressure of CO2in the arterial blood, additionally, levels of TNF-α, IL-6and IL-8were lower than in the control group, there were statistical differences between the two groups.Conclusion:Inverse ratio ventilation not only reduces the peak airway pressure and release of inflammatory cytokine, but also increases the mean airway, improves the oxygenation and dynamic compliance of lung in obese patients undergoing gynecologic laparoscopy without adverse respiratory or hemodynamic...