Effect Of Preoperative Use Of Shenfu Injection On Hemodynamics, RSO₂,Serum Level Of SOD And MDA In Patients Undergoing Thoracic Surgery With One-Lung Ventilation

Objective:With the change of modern life style and the deterioration of living environment,more and more patients suffer from intra-thoracic diseases and are undergoing thoracic surgery.In most of thoracic surgeries,one-lung ventilation is often required for convenience of surgical manipulation.However,unilateral ventilation can interfere with normal physiological mechanisms of the body,including respiratory and cardiovascular system.The effects of one lung ventilation on respiratory function include mainly the following:1.Increased pulmonary vascular resistance;2.Changes of difference of alveolar-arterial oxygen tension;3.Increased mechanical stress;4.Inflammatory response;5.Hypoxic pulmonary vasoconstriction in non-ventilated lung;6.Reduction of lung function residual capacity.In addition,during thoracic surgery,the heart are often affected by surgical manipulations such as retraction or compression,reflective conduction block and even cardiac arrest which can result in decreased cardiac contraction force,reduction of cardiac output and coronary perfusion.Moreover,the vegetative nerve in the thoracic cavity is abundant,and sympathetic nervous system and parasympathetic nervous system are susceptible to surgical interference,which is likely to result in relatively insufficient blood volume due to dilation of blood vessels.All these factors above may lead to imbalance of cerebral oxygen supply and demand,manifested as reduction of oxygen saturation in the brain.Therefore,change of local cerebral oxygen saturation during single lung ventilation is concerned recently and becoming more and more important in clinical practice.Some studies demonstrated that even the patient's hemodynamic seems stable,decrease in local brain oxygen saturation may occur,and this reduction of rSO₂is considered to be closely related to abnormal cerebral function such as postoperative cognitive dysfunction.Previous studies suggested that Shenfu injection may be effective to ameliorate microcirculation.But,it is not well known whether Shenfu injection would improve cerebral oxygen saturation.This randomized and controlled clinical trial is carried out to investigate the effect of Shenfu injection on cerebral oxygen saturation,hemodynamics and oxidative stress response in patients undergoing thoracic surgery with one lung ventilation.Methods:1.Patients undergoing elective thoracic surgery were recruited according to the enrolling criteria.All patients were assigned randomly and respectively into Shenfu group and control group.2.After arriving operating room,the patients'vital signs,BIS,rSO₂ and hemodynamics were monitored and recorded continuously.3.Intravenous instillation of 1.5ml/kg ShenFu?in ShenFu group?or1.5ml/kg saline?in control group?was used 30 min before anesthetic induction and fulfilled within 5 minutes.4.The appropriate double endotracheal tube?for pulmonary surgery or Mediastinal surgery?or bronchial blockers tube?for esophageal surgery?was intubated after routine anesthesia induction.The tube was fixed properly after its position was clearly identified by fiberoptic bronchoscopy.Anesthesia was maintained by carefully adjusting the parameters of anesthesia machine and dosage of anesthetics,analgesics and muscle relaxant.5.Hydroxyethyl starch?or polypeptides?and sodium lactate solution were infused intravenously with average infusion rate of 8¹0 ml/kg/h during the operation.The requirements of liquid were calculated and adjusted according to intraoperative blood pressure,urine output and blood loss.If hypotension?reduced by or over 30%of base value?or/and bradycardia?HR<50 bpm?occur,then ephedrine?3mg?or/and atropine?0.2mg?is injected intravenously for correction.6.rSO₂,MAP,HR,SpO₂,cardiac output?CO?,cardiac index?CI?,stroke volume?SV?and stroke volume variation?SVV?,body temperature were monitored and recorded immediately before anesthesia induction?T1?,at 10min after intubation in supine position?T2?,10 min after bilateral ventilation in lateral position?T3?,45 min after one-lung ventilation?T4?,and 5 min after extubation?T5?.The arterial blood samples were withdrawn at T1-T5 for measurement of serum SOD and MDA concentrations.The dosage of anesthetics,fluid volume infused,blood loss,and urine output were recorded from arrival of patient into operating room to T5.The total dosage of atropine and ephedrine were also recorded during procedure.Results:1.At T2-T4,the values of CO,CI and SV in Shenfu injection group were higher than that in control group with significant difference?P<0.05?.2.There was no statistically significant difference in local cerebral oxygen saturation between two groups at baseline?T2??P>0.05?.Significant difference was found in cerebral oxygen saturation between groups at T4?P<0.05?.3.For some of patients were not consent to blood-drawing,only 10patients'blood samples were taken for measurement of serum SOD and MDA level.No statistically significant difference was observed between the two groups?P>0.05?.4.The differences in total dosage of atropine and ephedrine used intraoperatively were statistically significant between the two groups?P<0.05?.5.RSO2 has significant correlation with MAP and CO.Conclusion:1.Pretreatment with ShenFu injection 30min before anesthesia induction can stabilize hemodynamic in patients during thoracic surgery.2.Pretreatment with ShenFu injection 30min before anesthesia induction can improve the local cerebral oxygen saturation during one lung ventilation.3.No clear conclusion can be made to the effect of ShenFu injection on oxidative stress response during procedure and single lung ventilation with possible reason that no enough cases were observed in this study.4.RSO2 has significant correlation with MAP and CO.