Pilot Study Of Multi-functional Emergency Cardiac Pacing Via Bronchial Catheter

Object:How to improve the outcome and reduce the mortality of serious tardy arrhythmia is an important clinical issue. How to choose scientific, rapid and effective emergency cardiac pacing method to is a topic that medical care personnel have to face to. Emergency airway-cardiac pacing could perform emergency cardiac pacing as well as artificial respiratory support in the same time. This study aims to systematically compare the difference of efficiency and effectiveness between different air way pacing positions(including trachea, right main bronchus and left main bronchus) and cardiac pacing by balloon-tipped floating catheter, to display the characteristics and advantages of airway pacing, and to illuminate the preferred airway pacing method.Method: Adult crossbreed dogs were employed in this study. A classic tardy arrhythmia model of dog was established by electric stimulation on vague nerve. Basing on the anatomic relationship between trachea, bronchi and heart, we independently designed new type endotracheal tube pacing device in which pacing electrode was improved. To display the characters and advantages of different airway pacing methods, ECG, time of pacing building and pacing threshold were systematically compared among the trachea, right main bronchial, left main bronchial and balloon floating pacing groups, the preferred airway pacing method was illuminated as well.Results: 1) Effectiveness, according to ECG and hemodynamics index, cardiac pacing could be implemented effectively via transtracheal cardiac pacing, right/left main bronchial pacing, and balloon-tipped floating pacing respectively. 2) Pacing building time, transtracheal cardiac pacing improved significantly in efficiency, balloon-tipped floating catheter group(365±52.98s), transtracheal cardiac pacing group(40.38±4.57s), right main bronchial pacing group(41.79±3.04s), left main bronchial pacing group(45.82±3.16s). Pacing building time of all the transtracheal cardiac pacing group were significantly shorter than that in balloon-tipped floating catheter group( P﹤0.05). There was significant difference among groups determined by One-way anova Anova Analysis with P﹤0.05. Comparisons the pacing building time in different groups by T test: there was no significant difference of pacing building time between right main bronchial pacing group and transtracheal cardiac pacing group(P﹥0.05). Pacing building time in right main bronchial pacing group was shorter than that in left main bronchial pacing group, with significant difference(P﹤0.05). There was no significant difference of pacing building time between left main bronchial pacing group and transtracheal cardiac pacing group(P﹥0.05). 3) Pacing threshold, the pacing threshold of each group was: balloon-tipped floating catheter group(1.54±0.29V), transtracheal cardiac pacing group(11.75±0.76V), right main bronchial pacing(4.04±0.31V), left main bronchial pacing(9.32±0.90V). The pacing threshold in different groups were significant difference determined by One-way Anova Analysis(P﹤0.05). A significant difference of pacing threshold in different groups(P﹤0.05) were detected by T test analysis, and the pacing threshold of right main bronchial pacing group was minimum. 4) Preferred method of airway pacing, right main bronchial pacing was the preferred method of transtracheal cardiac pacing. The optimal pacing site in our study was located at the middle right main bronchial, and 39.80±0.61 cm from fore-tooth according to front/lateral chest radiographs and measure by fibroscopy.Conclusion: 1.This Our study results showed that the trachea pacing, right main bronchus bronchial pacing, and left main bronchus bronchial pacing can be able to perform effective cardiac pacing as the balloon-tipped floating pacing, which could be all reliable emergency cardiac pacing methods. 2. Results of our study demonstrated that the pacing building time of right main bronchial pacing group was shorter than that of left main bronchial pacing group. Among the three airway pacing groups, right main bronchial pacing group acquired the lowest threshold voltage; therefore we speculate that right main bronchial pacing method has more advantages in the efficiency and effectiveness comparing with other airway pacing methods. Our study provided experimental data and application basis for airway pacing methods. 3. We originally designed a kind of bronchial pacing catheter with specific airway pacing electrode, which has obtained invention patent. Experiment results displayed that this kind of bronchial pacing catheter could be easy to be fixed, closely touch with endobronchitis mucosea, own excellent electrical conductivity, and not damage the airway mucosea. 4. Emergency airway-cardiac pacing method provides a new idea and possibility for a rapid and effective establishment of artificial respiration and circulation during cardiopulmonary resuscitation.