Objective To confirm the difference between internal and external pressure of cervical esophageal and to discuss the relations between cervical esophageal pressure difference with the formation of cervical anastomotic leakage. Methods In the present study, 12 New Zealand white rabbits were used. We applied a pressure transducer to describe the variation of pressure of intrathoracic, thoracic esophagus, cervical esophagus and upper esophageal sphincter during resting and cough. Pressure value was recorded and read through MD3000 system. And the difference between each point was analyzed. Results The pressures resulting from the cough induced were significantly higher in intrathoracic than in thoracical esophagous (10.2±0.6 cm H2O vs. 36.7±1.0 cm H2O), exhibited significantly higher in upper esophageal sphincter and thoracic esophagous than in cervical esophageal (7.5±0.2 cm H2O vs. 12.0±0.4 cm H2O, vs. 10.2±0.6 cm H2O). Conclusion Cervical anastomotic leaks are affected by many factors.And the most notabe one is the constant pressure from inside-out around cervical anastomotic.
Objective To explore the feasibility of establishing a rabbit model of flail chest. Methods Flail chest model was eatablished in 12 New Zealand white rabbits after anesthesia and sterile surgery. The paradoxical movement of chest wall was recorded by the biological signal acquisition system, arterial blood was collected for blood gas analysis, the vital signs were recorded by electrocardiogram (ECG) and the lung tissue was taken for the pathological analysis at the end of the experiment. The effect of flail chest on the respiratory function of experimental animals was analyzed to evaluate the feasibility of establishing flail chest model. Results All surgeries were successful without mortality. The operation time was 41.42±7.08 min. Duration of endotracheal intubation was 79.33±12.21 min. Statistical results showed that the pH, partial pressure of arterial carbon dioxide (PaCO2) and base excess (BE) increased; while partial pressure of oxygen (PaO2) and oxygen saturation (SaO2) reduced. Pathological results showed that flail chest not intervented for a long period would lead to organic lesions. Conclusion The rabbit model of flail chest is feasible, safe, repeatable, easy and simple to handle. The animal is easy to access which is the foundation to study the disease process, recovery procedure and the efficacy after intervention.