Effects Of Remimazolam On Hemodynamics,Respiratory Function And Postoperative Cognitive Function In Elderly Patients Undergoing Lobectomy

Objectives:To investigate the effects of remimazolam on intraoperative hemodynamics,postoperative cognitive function and oxygenation in elderly patients undergoing lobectomy.Methods:Eighty-four elderly patients with lung cancer who underwent lobectomy were assigned to the remimazolam group(Group R:0.3 mg/kg and 0.6～1.2 mg.kg^-1.h^-1for induction and maintenance)and propofol group(Group P:2 mg/kg and 2～10mg.kg^-1.h^-1for induction and maintenance)by the random number table method.The hemodynamic indicators（SBP,MAP,HR,cardiac index[CI],systemic vascular resistance index[SVRI],left ventricular systolic force index[d Pmax]and pulse pressure variability[PPV]）were monitored by using the pulse index continuous cardiac output（PICCO）at 5 min before induction（T0）,1 min after sedative administration（T1）,2 min after sedative administration（T2）,when the double-lumen bronchial catheter passed through the tracheal carina（T3）,5 min after intubation（T4）,10 min after intubation（T5）,the beginning of the operation（T6）,one lung ventilation（OLV）30 min（T7）,OLV 60 min（T8）and end of the operation（T9）.The cognitive function was assessed using neuropsychological tests 1 day before surgery and 7 days after surgery:the Clock Drawing Test（CDT）,the Verbal Fluency Test（VFT）,the Digit Symbol Switching Test（DSST）and the Auditory Verbal Learning Test-Huashan（AVLT-H）were used to assess visuospatial ability,language ability,attention and memory of patients in Group R and Group P,respectively.The arterial oxygen partial pressure（PaO₂）,oxygenation index（OI）,lactate and blood glucose were assessed at T0,T4,T7,T8 and T9.Central nervous system-specific protein（S-100β）and interleukin-6（IL-6）in central venous blood were measured at T0,T9,24 hours after surgery（T10）and on Day 7 after surgery（T11）.Modified Observer’s Assessment of Alertness/Sedation（MOAA/S）,bispectral index（BIS）and adverse events were recorded.Results:（1）From T4 to T9,the SBP,MAP,SVRI and d Pmax were significantly higher in Group R compared to Group P（P<0.05）.HR、PPV、CVP、and CI were not significantly different between the two groups（P>0.05）.The incidence of hypotension was significantly lower in the Group R（9.5%）than in the Group P（35.74%）（P=0.004）,and remimazolam significantly reduced the dose of phenylephrine used（P<0.05）.（2）The VFT,DSST,immediate recall and short-delayed recall scores were significantly higher in the Group R than in the Group P on Day 7 after surgery（P<0.05）.（3）There was no significant difference in IL-6 between the two groups at each time point（P>0.05）.At T 9 time point,S-100βin Group R was significantly lower than that in Group P（P<0.05）.（4）The PaO₂and OI at T8 were significantly higher in the Group R than in the Group P（P<0.05）.（5）BIS,MOAA/S,lactate and blood glucose were not significantly different between the two groups（P>0.05）.Conclusion:1.Compared with propofol,remimazolam optimize intraoperative hemodyna-mics,and the increased systemic vascular resistance and myocardial contractility of remimazolam may be one of the main reasons for its maintenance of stability hemodynamics compared with propofol.2.Compared with propofol,remimazolam reduced S-100βand lessen the degree of short term postoperative cognitive dysfunction.3.Compared with propofol,remimazolam improved respiratory function during OLV.