Effects Of CO₂ Pneumoperitoneum On Hemodynamics And Oxygen Saturation Of Muscle Tissue In Patients Undergoing Laparoscopic Total Hysterectomy

Objective:To observe the changes of hemodynamics and SmtO₂ after the establishment of CO₂ pneumoperitoneum during general anesthesia and the relationship between them.Method:Patients who met the requirements of the test were selected.The patients were admitted to the operating room,and HR,NBP,SpO₂,Temp and BIS were routinely monitored.Non-invasive hemodynamic monitoring was performed by LiDCOrapid.If the patient complained of tension,anxiety or vital signs such as heart rate and blood pressure were 20%higher than the basic ward value,propofol 10-30mg were given intravenously.Anesthesia induction with 6 L/min pure oxygen to give oxygen to nitrogen,in turn,intravenous propofol 2 mg/kg,cisatracurium 0.2 mg/kg,sufentanial 0.3μg/kg,the rapid induction,endotracheal intubation technique,connected breathing machine,by adjusting the parameters of the breathing machine,capacity control of mechanical ventilation mode,set up 1:1 mixed air oxygen inhaled,fresh gas flow 2 L/min,tidal volume for 6⁸ mL/kg,breathing rate10²0 times/min,the absorption/exhalation ratio is 1:1.5²,maintain P_ETCO₂in 35⁴5 mmHg.Propofol 4¹0mg·kg^-1·h^-1 combined with continuous intravenous infusion of remifentanil 0.01⁰.03ug·kg^-1·min^-1,BIS value 40⁶5was maintained.Maintain Temp36³7.5℃.Cisatracurium were given to maintain muscle relax.Dizocine were given intravenously for postoperative analgesia.All patients were sent to PACU after surgery.Intraoperative CO₂pneumoperitoneum pressure was 12mmHg.The general information of patients（age,height,weight,ASA grading,hemoglobin）,continuous pneumoperitoneum time were recorded.And the values of CO,CI,SV,SVR,MAP and brachioradialis muscle SmtO₂ were recorded at resting state before anesthesia induction（T₀）,5min before pneumoperitoneum（T₁）,pneumoperitoneum（T₂）,5min（T₃）and 10 min（T₄）after pneumoperitoneum,deflating pneumoperitoneum（T₅）and 5min after deflating CO₂ pneumoperitoneum（T₆）.Results:1.Influence of CO₂ pneumoperitoneum on hemodynamic indexesCompared with T₀,HR,CO,CI,SV and MAP decreased at T₁（P<0.05）,while SVR showed no significant difference（P>0.05）.At T₂ and T₃,HR,CO,CI,MAP and SV decreased,while SVR increased（P<0.05）.At T₄,HR,CO,CI and MAP decreased,SVR increased（P<0.05）,and SV difference was not statistically significant（P>0.05）.At T₅ and T₆,HR and MAP decreased（P<0.05）,while SV,SVR,CO and CI showed no significant difference（P>0.05）.Compared with T₁,at T₂,CO,CI and SV decreased,SVR increased（P<0.05）,while HR and MAP showed no significant difference（P>0.05）.At T₃,SV decreased and SVR increased（P<0.05）,but the differences in CO,CI,MAP and HR were not statistically significant（P>0.05）.At T₄,SVR and MAP increased（P<0.05）,while CO,CI,SV and HR showed no significant difference（P>0.05）.There was no significant difference in CO,CI,SV,SVR and MAP（P>0.05）.At T₆,CO and CI decreased and HR increased（P<0.05）,while SV,SVR and MAP showed no significant difference（P>0.05）.Compared with T₂,HR and MAP increased at T₃（P<0.05）,while CO,CI,SV and SVR showed no significant difference（P>0.05）.At T₄,HR and MAP increased,while CO and CI decreased（P<0.05）,while SV and SVR showed no significant difference（P>0.05）.At T₅ and T₆,HR and SV increased,CO,CI and SVR decreased（P<0.05）,and MAP showed no significant difference（P>0.05）.Compared with T₃,CO and CI increased at T₄（P<0.05）,while HR,SV,SVR and MAP showed no significant difference（P>0.05）.At T₅ and T₆,CO,CI,HR and SV increased,while SVR and MAP decreased（P<0.05）.When compared with T₄,HR increased at T₅ and T₆,SVR and MAP decreased（P<0.05）,and there was no significant difference in CO,CI and SV（P>0.05）.Compared with T₅,HR,CO,CI,SV,SVR and MAP at T₆ showed no significant difference（P>0.05）.See Table 2.2.Effect of CO₂ pneumoperitoneum on brachioradialis muscle SmtO₂Compared with T₀,SmtO₂ decreased at T₂,T₃,T₄ and T₅（P<0.05）,there was no significant difference in SmtO₂ level at T₁ and T₆（P>0.05）.Compared with T₁,SmtO₂ decreased at T₃ and T₄（P<0.05）,while there was no significant difference in SmtO₂ at T₂,T₅ and T₆（P>0.05）.Compared with T₂,SmtO₂ decreased at T₃ and T₄,（P<0.05）;while there was no significant difference in SmtO₂ at T₅ and T₆,（P>0.05）.There was no significant difference in SmtO₂ at T₃,T₄,T₅ and T₆,and no significant difference in pairwise comparison（P>0.05）.See Table 3.3.Relationship between hemodynamics and brachioradialis muscle SmtO₂There was a low positive correlation between HR,CO,CI and SmtO₂（r=0.257,0.212,0.202,P<0.05,respectively）.There was a low negative correlation between SVR and SmtO₂（r=-0.165,P<0.05）.As shown in Table 3.4.Effects of CO₂ pneumoperitoneum on brachioradialis muscle SmtO₂ in different hemoglobin populationsAnemia was determined according to whether the Hb was higher than110g/L.Among the 39 patients,28 were normal and 11 were anaemic.There were no significant differences in general condition indexes between the normal group and the anemia group（P>0.05）,as shown in Table 4.There was no significant difference in brachioradialis muscle SmtO₂ level between the normal group and the anemia group at each time point（P>0.05）.In the normal hemoglobin group,SmtO₂ changes were significantly different at different times of pneumoperitoneum establishment（P<0.05）,and SmtO₂ level reached the lowest value at T₄.There were no significant differences in brachioradialis muscle SmtO₂ before and after the establishment of pneumoperitoneum in the anemia group（P<0.05）,as shown in Table 5.Conclusion:1.General anesthesia and laparoscopic pneumoperitoneum establishment have an impact on non-invasive hemodynamic parameters under LiDCOrapid monitoring.2.CO₂ pneumoperitoneum under general anesthesia is the main factor causing the decline of brachioradialis SmtO₂.3.Brachioradialis SmtO₂ was positively correlated with changes in HR,CO and CI;It is negatively correlated with SVR change.4.The effect of CO₂ pneumoperitoneum under general anesthesia on the brachioradialis SmtO₂ in normal hemoglobin population and anemia population is different.