Objective To study the effects of different levels of intra-abdominal pressure （IAP） on hemodynamics and oxygen metabolism in pig and to find the parameters early reflecting hemodynamics and oxygen metabolism of intra-abdominal hypertension （IAH）. Methods Fifteen pigs were anaesthetized, and trachea intubation and transfemoral cannula were performed then. Swan-Ganz catheters were inserted to pulmonary artery via internal jugular vein, and aeroperitoneum was set up by airing CO2. These pigs were randomly divided into three groups (5 pigs in each group) according to different levels of IAP （IAP10, IAP20, IAP30）. Hemodynamics and oxygen metabolism values were observed and recorded before airing, 6, 12, 18 and 24 hours after airing, respectively. Results There was no remarkable changes of hemodynamics and oxygen metabolism values in IAP10 group （Pgt;0.05）； When the IAP level reached 20 cm H2O, there was significant elevation （P＜0.01) in artery blood lacticacid （ABL）, and mixed venous oxygen saturation （SvO2） decreased significantly （P＜0.05) at 24 hours. When the IAP level reached 30 cm H2O, HR began to increase significantly at 18 hours after airing （P＜0.05). After 24 hours, all the indices of hemodynamics and oxygen metabolism were either significantly increased or decreased in IAP30 group. Two pigs in the group of IAP30 died during 24 hours after airing, while other pigs survived. Conclusion This study demonstrates that the hemodynamics and oxygen metabolism values begin to change in pigs when the IAP level reaches 20 cm H2O, and high level of IAP that lasted for 24 hours shows deterioration of hemodynamic and oxygenation levels. The indices of SvO2 and ABL can early reflect tissue oxygenation in IAH.
Objective To investigate the effect of intra-abdominal hypertension(IAH) on respiratory function in pigs.Methods Twelve pigs were randomly divided into two groups (n=6 in each group),ie.IAH20 group(intra-abdominal pressure=20 mm Hg) and IAH30 group(intra-abdominal pressure=30 mm Hg).Pig model of IAH was established by intraperitoneally injection of carbon dioxide.The changes in respiratory function parameters including pulmonary dynamic compliance（Cdyn），peak inspiratory pressure(PIP) ,SpO2 and PaCO2 were recorded at different time points.Results Cdyn was significantly decreased at different time points compared with baseline in group IAH30 and group IAH20.PIP significantly increased at different time points compared with baseline in both IAH groups，but group IAH30 was more severe than group IAH20. No significant changes of SpO2 and PaCO2 were found in two IAH groups.Conclusion IAH can impair respiratory function by decreasing lung compliance and increasing inspiratory pressure.