Abstract：
BACKGROUND: High peak airway pressure (Ppeak) and high end-tidal carbon dioxide tension (PETCO2) are the common problems encountered in the obese patients undergoing gynecological laparoscopy with conventional volume-controlled ventilation. This study was designed to investigate whether volume-controlled inverse ratio ventilation (IRV) with inspiratory to expiratory (I:E) ratio of 2:1 could reduce Ppeak or the plateau pressure (Pplat), improve oxygenation, and alleviate lung injury in patients with normal lungs.
METHODS: Sixty obese patients undergoing gynecological laparoscopy were enrolled in this study. After tracheal intubation, the patients were randomly divided into the IRV group (n = 30) and control group (n = 30). They were ventilated with an actual tidal volume of 8 mL/kg, respiratory rate of 12 breaths/min, zero positive end-expiratory pressure and I:E of 1:2 or 2:1. Arterial blood samples, hemodynamic parameters, and respiratory mechanics were recorded before and during pneumoperitoneum. The concentrations of tumor necrosis factor-α, and interleukins 6 and 8 in bronchoalveolar lavage fluid were measured immediately before and 60 minutes after onset of CO2 pneumoperitoneum.
RESULTS: IRV significantly increased arterial partial pressure of oxygen, mean airway pressure, and dynamic compliance of respiratory system with concomitant significant decreases in Ppeak and Pplat compared to conventional ventilation with I:E of 1:2 (p < 0.05). Additionally, the levels of tumor necrosis factor-α, and interleukins 6 and 8 were significantly lower than those in control group (p < 0.05).
CONCLUSIONS: Volume-controlled IRV not only reduces Ppeak, Pplat, and the release of inflammatory cytokines, but also increases mean airway pressure, and improves oxygenation and dynamic compliance of respiratory system in obese patients undergoing gynecologic laparoscopy without adverse respiratory and hemodynamic effects. It is superior to conventional ratio ventilation in terms of oxygenation, respiratory mechanics and inflammatory cytokine in obese patients undergoing gynecologic laparoscopy.
METHODS: Sixty obese patients undergoing gynecological laparoscopy were enrolled in this study. After tracheal intubation, the patients were randomly divided into the IRV group (n = 30) and control group (n = 30). They were ventilated with an actual tidal volume of 8 mL/kg, respiratory rate of 12 breaths/min, zero positive end-expiratory pressure and I:E of 1:2 or 2:1. Arterial blood samples, hemodynamic parameters, and respiratory mechanics were recorded before and during pneumoperitoneum. The concentrations of tumor necrosis factor-α, and interleukins 6 and 8 in bronchoalveolar lavage fluid were measured immediately before and 60 minutes after onset of CO2 pneumoperitoneum.
RESULTS: IRV significantly increased arterial partial pressure of oxygen, mean airway pressure, and dynamic compliance of respiratory system with concomitant significant decreases in Ppeak and Pplat compared to conventional ventilation with I:E of 1:2 (p < 0.05). Additionally, the levels of tumor necrosis factor-α, and interleukins 6 and 8 were significantly lower than those in control group (p < 0.05).
CONCLUSIONS: Volume-controlled IRV not only reduces Ppeak, Pplat, and the release of inflammatory cytokines, but also increases mean airway pressure, and improves oxygenation and dynamic compliance of respiratory system in obese patients undergoing gynecologic laparoscopy without adverse respiratory and hemodynamic effects. It is superior to conventional ratio ventilation in terms of oxygenation, respiratory mechanics and inflammatory cytokine in obese patients undergoing gynecologic laparoscopy.
摘要：
背景：高峰值气道压（Ppeak）和高呼气末二氧化碳张力（PETCO2）是肥胖患者在接受常规容量控制通气的妇科腹腔镜检查时遇到的常见问题。这项研究旨在研究吸气与呼气（I：E）比率为2：1的容量控制的逆比通气（IRV）是否可以降低Ppeak或平台压力（Pplat）。改善氧合，减轻肺正常患者的肺损伤。
方法：本研究纳入60例接受妇科腹腔镜检查的肥胖患者。气管插管后,随机分为IRV组(n=30)和对照组(n=30)。它们以8mL/kg的实际潮气量通风，呼吸频率为12次呼吸/分钟，零呼气末正压和I:E为1:2或2:1。动脉血样本,血液动力学参数,在气腹之前和期间记录呼吸力学。肿瘤坏死因子-α的浓度，在CO2气腹开始之前和之后60分钟测量支气管肺泡灌洗液中的白细胞介素6和8。
结果：IRV显著增加动脉氧分压，平均气道压,与I：E为1：2的常规通气相比，呼吸系统的动态顺应性伴随着Ppeak和Pplat的显着降低（p<0.05）。此外,肿瘤坏死因子-α的水平，白细胞介素6和8显著低于对照组(p<0.05)。
结论：体积控制的IRV不仅可以降低Ppeak，Pplat,和炎症细胞因子的释放，但也会增加平均气道压力，在接受妇科腹腔镜检查的肥胖患者中，改善了氧合和呼吸系统的动态依从性，而没有不良的呼吸和血流动力学影响。在氧合方面优于常规比例通气，肥胖患者接受妇科腹腔镜检查的呼吸力学和炎性细胞因子。
方法：本研究纳入60例接受妇科腹腔镜检查的肥胖患者。气管插管后,随机分为IRV组(n=30)和对照组(n=30)。它们以8mL/kg的实际潮气量通风，呼吸频率为12次呼吸/分钟，零呼气末正压和I:E为1:2或2:1。动脉血样本,血液动力学参数,在气腹之前和期间记录呼吸力学。肿瘤坏死因子-α的浓度，在CO2气腹开始之前和之后60分钟测量支气管肺泡灌洗液中的白细胞介素6和8。
结果：IRV显著增加动脉氧分压，平均气道压,与I：E为1：2的常规通气相比，呼吸系统的动态顺应性伴随着Ppeak和Pplat的显着降低（p<0.05）。此外,肿瘤坏死因子-α的水平，白细胞介素6和8显著低于对照组(p<0.05)。
结论：体积控制的IRV不仅可以降低Ppeak，Pplat,和炎症细胞因子的释放，但也会增加平均气道压力，在接受妇科腹腔镜检查的肥胖患者中，改善了氧合和呼吸系统的动态依从性，而没有不良的呼吸和血流动力学影响。在氧合方面优于常规比例通气，肥胖患者接受妇科腹腔镜检查的呼吸力学和炎性细胞因子。
