Safety Analysis Of Application Of Mediastinal CO₂ Aeration In Mediastinal Esophagectomy

Objective In recent years,minimally invasive esophagectomy(MIE)has been used gradually in esophageal surgery.The application of CO2 aeration in minimally invasive surgery,especially in laparoscopic surgery,has been very mature.However,the application of mediastinal esophagectomy is still in the exploration stage.This study was designed to investigate the safety of mediastinal CO2 aeration in the mediastinal esophagectomy.Methods By cell functional assay,the effects of different inflation pressures on proliferation,apoptosis,invasion and metastasis of esophageal cancer cells were studied by in vitro simulation of mediastinal CO2 aeration.The pigs were used to construct an experimental animal model of mediastinal CO2 aeration.The effects of different inflation pressures on the circulatory respiratory function of pigs were studied by detecting the relevant physiological parameters.10 patients with early esophageal cancer treated in Changzhou First People's Hospital were randomly selected.Those patients underwent mediastinal esophagectomy with CO2 inflation.HR,MAP and CVP of patients were monitored before ventilating CO2,30,60,90 min after inflation and 30 min after deflation.Arterial blood was collected for PaCO2,blood lactate concentration,PaO2/FiO2,SaO2,pH value,and cardiac output(CO)was measured by esophageal ultrasound.Results The results of cell function experiments showed that 5-10mmHg CO2 inflation pressure had no significant effect on proliferation,apoptosis,migration and invasion of esophageal cancer cells;however,15mmHg CO2 inflation pressure could promote the proliferation,migration and invasion of esophageal cancer cells and inhibit the apoptosis of esophageal cancer cells.Animal experiments showed that under 5-10mmHg CO2 inflation pressure,circulation function indicators(CVP,systolic blood pressure,diastolic blood pressure,pulse pressure difference,heart rate,cardiac output)and respiratory function indicators(PaCO2,blood lactate concentration?PaO2/FiO2?SaO2?pH value)in pigs had no significant difference compared with the indicators before inflation;and under 15mmHg CO2 inflation pressure,CVP,heart rate,PaCO2 and blood lactate concentration increased,while blood pressure,cardiac output,PaO2,SaO2 and pH values decreased.In addition,heart rate was remarkably increased under 10mmHg CO2 inflation pressure,however there were no significant differences in other circulation and respiratory function indicators in patients receiving esophageal cancer resection with mediastinal CO2 inflation.Conclusion Mediastinal esophagectomy with 5mmHg and 10mmHg CO2 inflation pressure has no significant effect on the circulation and respiratory function of the body or proliferation and metastasis of esophageal cancer.Although 10mmHg mediastinal CO2 pressure could have a limited effect on the circulatory system,for which the human body could rewire itself to compensate.The pressure gradient between mean circulation filling pressure(MCFP)and CVP during surgery.