急性气胸对家兔呼吸、血压及心电图的影响

目的探讨急性气胸对家兔呼吸、血压及心电图的影响。方法家兔11只,于右胸腋前线第7-8肋间造一裂口,建立急性气胸模型。记录气胸时和气胸5min后的呼吸、血压和心电图(标准Ⅱ导联)变化,分别与气胸前各项指标相比较。结果气胸时与气胸前相比:呼吸加快8例,减慢3例;血压下降7例,上升4例。气胸5min后与气胸前相比:心率减慢、P波时间延长、P-R间期延长、QRS间期延长、ST段电压升高、T波电压升高、QT间期延长(P<0.01或0.05);P波电压、R波电压、S波深度下降,但不明显(P>0.05)。结论随着气胸量的增加心电图各参数的变化越明显,心电图改变以ST段电压升高最明显,提示气胸时有心肌缺血的可能。

The respiration, blood pressure and ECG changes induced by acute pneumothorax

Objective To investigate the effect of acute pneumothorax on the respiration, blood pressure and ECG in rabbits. Methods 11 rabbits bred in family were involved in the experiment. A breach was made between 7～8 rib in the right thoracic anterior axillary line for building up the acute pneumothorax model. The changes of the respiration, blood pressure and ECG (standard lead Ⅱ) during pneumothorax and 5 minutes after pneumothorax were recorded. A comparison of these indexes between in-pneumothorax, post-pneumothorax and pre-pneumothorax had been done. Results In comparison to those indexes of pre-pneumothorax, during pneumothorax: 8 cases with accelerated respiration, 3 with slow respiration; 7 with decreased blood pressure, 4 with elevated blood pressure. 5 minutes after pneumothorax: the heart rate was reduced, P-wave prolonged, P-R intermittent prolonged, QRS intermittent proloned, ST electric voltage elevated, QT intermittent prolonged (P<0.01 or 0.05); P-wave electric voltage, R-wave electric voltage and S-wave decreased, but there was no statistically significant difference (P>0.05). Conclusions With the increasing of the pneumothorax content, the changes of the ECG parameters were obvious, ST elevated most significantly. It suggested myocardial ischemia might occur during pneumothorax.