Abstract: ［Abstract］  Objective〖HTSS〗〓To examine the improvement of Bilevel positive airway pressure（BiPAP) ventilation therapy on right ventricular function in chronic obstructive pulmonary disease（COPD） patients combined with respiratory failure by Tei index. To discuss if Tei index is valuable to predict the time for taking off ventilatior.
〖HTH〗〖WTHZ〗Methods〖HTSS〗〓Fortyeight cases of COPD patients combined with respiratory failure were selected in ICU of our hospital, all of whom were given invasive mechanical ventilation with oral trachea cannula. Then the blood gas analysis and bedside echocardiography were examined in the first day(before BiPAP therapy), the second day and the fifth day after entering ICU. The heart rate(HR), respiratory rate(RR), power of hydrogen(PH), partial pressure of oxygen(PO2), partial pressure of carbon dioxide(PCO2), saturation oxygen(SO2), right ventricular diameter（RV), right ventricular anterior wall thickness（RVAW), pulmonary arterial systolic pressure（PASP) and right ventricular Tei index were recorded and compared among the three time spot. The patients were divided into two groups called successful takingoff group and failure takingoff group according to if they had been taken off ventilatiors or not in the fifth day. Tei index was compared between the two groups in the three different time spots.
〖HTH〗〖WTHZ〗Results〖HTSS〗〓Compared with the indexes in the first day, the heart rate, respiratory rate and blood gas analysis of the patients were significantly improved and the PASP, right ventricular Tei index were significantly better in the second and fifth day(P＜005), and the difference was statistically significant. While the difference of RV and RVAW had no statistical significance. The difference of all the index between the second day and the fifth day had no statistical significance. With the time lapsing, The Tei index of the two groups was in a downward trend and the dates of the successful takingoff group declined by a large margin. The difference between groups,among time spots and among crossover effect of time and grouping factor had statistical significance.
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗〓Invasive BiPAP ventilation can obviously improve the right ventricular function and cure rate in COPD patients combined with respiratory failure. Tei index is a sensitive index for evaluating right heart function and may be valuable to predict the time for taking off ventilatior.

Key words: pulmonary disease, chronic obstructive, respiratory insufficiency, respiration, artificial