Investigation of Artificial Ventilation with Permissive Hypercapnia in Dogs

犬允许性高碳酸血症的人工通气研究

• 批准号: 07671675
• 负责人: UJIKE Yoshihito
• 金额: $ 1.15万
• 依托单位: MIYAZAKI MEDICAL COLLEGE
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1996
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07671675/
• 关键词: permissive hypercapnia; animal experiment; respiratory response; hemodynamics; intracranial pressure; tissue acid-base balance; 組織血流; 酸素代謝; 換気力学

Objectives and Methods : 1) An objective of my investigation is to evaluate the respiratory mechanics and hemodynamics during permissive hypercapnia (PHY) using partial assist ventilation. We produced respiratory failure with oleinic acid on five dogs and ventilated them by pressure support ventilation. The blood gas, the respiratory mechanics and hemodynamics were measured at the support pressure of 30 cmH_2O,25cmH_2O,15cmH_2O,and 5cmH_2O.2) The other objective of my investigation is to evaluate the hemodynamics, intracranial pressure (ICP), tissue acid-base balance and tissue blood flow-oxygenation in induced hypercapnia. We ventilated seven dogs with volume control ventilation and measured the blood gas, hemodynamics, intracranial pressure and tissue pH (pHi) at the tidal volume of 10 ml/kg, 8 ml/kg, and 6 ml/kg.Results : 1) The respiration and hemodynamics were not changed abnormally at the support pressure of 30 cmH_2O and 25 cmH_2O.Although PaCO_2 did not change, the respiratory … More rate, peak inspiratory flow, work of breathing of patient (WOBp) and heart rate increased at the support pressure of 15 cmH_2O.In addition of these parameters, PaCO_2 increased at the support pressure of 5cmH_2O.2) By changing the tidal volume from 10 ml/kg to 8 ml/kg, the average of PaCO_2, mean pulmonary pressure (mPAP) and ICP elevated from 35.7 mmHg to 57.8 mmHg, from 19.3 mmHg to 22.8 mmHg, and from 19.3 mmHg to 27.5 mmHg respectively and pH decreased from 7.384 to 7.214. The average of PaCO_2, pH,pHi, mPAP,and ICP reached to 90.4 mmHg, 7.057,6.986,26.5 mmHg, and 38.1 mmHg after changing the tidal volume to 6ml/kg.Conclusions : 1) PHY with partial assist ventilation mode is possible in moderate respiratory failure. The partial assist ventilation, however, should be changed to a control ventilation mode when PaCO_2 elevates besides increases of respiratory rate, WOBp and hheart rate. 2) PHY should be avoided on the patients who have the danger of elevation of ICP and heart failure. PHY,however, did not change pHi critically. Less

目的和方法：1)本研究的目的是评估使用部分辅助通气时允许性高碳酸血症（PHY）的呼吸力学和血流动力学。我们用油酸对5只狗进行了呼吸衰竭，并对它们进行了压力支持通气。在30 cmH_2O、25cmH_2O、15cmH_2O和5cmH_2O的支撑压力下，测量血气、呼吸力学和血流动力学。2)本研究的另一个目的是评估血流动力学、颅内压（ICP）、组织酸碱平衡和组织血流氧合在诱导高碳酸血症中的作用。对7只狗进行容量控制通气，在潮气量为10 ml/kg、8 ml/kg和6 ml/kg时测量血气、血流动力学、颅内压和组织pH （pHi）。结果：1)在30 cmH_2O和25 cmH_2O支持压下，呼吸和血流动力学无异常变化。虽然PaCO_2没有变化，但在15 cmH_2O的支持压力下，呼吸频率、吸气峰值流量、呼吸功（WOBp）和心率均有所增加。此外，在5cmH_2O的支撑压力下，PaCO_2增加。2)将潮气量从10 ml/kg改变为8 ml/kg， PaCO_2平均值、平均肺动脉压（mPAP）和ICP分别从35.7 mmHg升高到57.8 mmHg、19.3 mmHg升高到22.8 mmHg、19.3 mmHg升高到27.5 mmHg， pH从7.384降低到7.214。当潮气量为6ml/kg时，PaCO_2、pH、pHi、mPAP和ICP的平均值分别为90.4 mmHg、7.057 mmHg、6.986 mmHg、26.5 mmHg和38.1 mmHg。结论：1)局部辅助通气模式的PHY在中度呼吸衰竭中是可行的。当PaCO_2升高，呼吸频率、WOBp和心率升高时，应将部分辅助通气改为控制通气模式。2)有颅内压升高和心力衰竭危险的患者应避免使用PHY。然而，PHY对pHi的影响并不明显。少