Effect Of Intravenous Pump Dexmedetomidine Combined With TAP Block On Postoperative Recovery In Elderly Patients Undergoing Laparoscopic Radical Gastrectomy

Objective:To observe the effects of dexmedetomidine（Dex）combined with multi-modal analgesia（MMA）in ultrasound guided transversus abdominis plane（TAP）block on postoperative analgesia and early recovery in elderly patients undergoing laparoscopic radical gastrectomy.Methods:A total of 72 elderly patients undergoing laparoscopic radical gastrectomy for gastric cancer were selected and assigned to control group（group C,n=36）and trial group（group TD,n=36）by random number table method.Each patient signed an informed consent to anaesthetize before entering the operating room.Group C was treated with endotracheal intubation and inhalation combined with general anesthesia.Group TD was treated with bilateral transverse fascial block under ultrasonic guidance before general anesthesia,after successful block,dexmedetomidine was pumped and then treated with endotracheal intubation and inhalation combined with general anesthesia.TAP block was performed by the same experienced anesthesiologist under ultrasound guidance,and local anesthesia was administered with 0.375%ropivacaine 40ml+5mg dexamethasone.20ml for left and right sides.Patients in group C were treated with sufentanil 2ug/kg and ondansetron 0.5mg/kg via intravenous patient-controlled analgesia（PCIA）,while patients in group TD were treated with sufentanil 1ug/kg and dexmedetomidine 5ug/kg via intravenous patient-controlled analgesia（PCIA）.Record the SBP and HR after admission（T₀）,induction of anesthesia（T₁）,skin cutting（T₂）,pneumoperitoneum establishment（T₃）,extubation（T₄）,and exit from PACU（T₅）,dosage of sufentanil and remifentanil in perioperative period;VAS score at resting state at each time point,and the number of compressions through intravenous patient-controlled analgesia after surgery;Ramsay sedation score,MMSE score and AIS score at each time point;C-reactive protein（CRP）content in venous blood 72h after operation;The postoperative hospital stay,the first time to exhaust,the time to get out of bed,the incidence of nausea and vomiting.Results:There were no significant differences in age,gender,BMI,ASA classification,education level and operation duration between the two groups.In terms of hemodynamics,SBP and HR decreased in both groups at T₁,compared with group C,SBP in group TD was higher at T₁（P<0.05）.The HR and SBP in TD group were lower at T₂,T₃ and T₄ than those in C group（P<0.05）.The amounts of sufentanil and remifentanil in group TD during perioperative period were significantly lower than those in group C（P<0.05）.The VAS score of TD group at 24h and 48h after surgery was lower than that of C group（P<0.05）,and there was no significant difference between group C at the time of leaving PACU（P>0.05）.The number of PCIA compressions in TD group was less than that in C group（P<0.05）.The Ramsay sedation scores at T₅,24h and 48h after surgery in TD group were higher than those in C group（P<0.05）.There was no significant difference in postoperative 72h MMSE scores between the two groups（P>0.05）,but the postoperative 72h MMSE score of TD group was higher than that of C group（P<0.05）,the lower the MMSE score 72h after surgery,the higher the C-reactive protein content detected 72h after surgery.The AIS scale score 24 hours after surgery in TD group was lower than that in C group（P<0.05）,there was no statistically significant difference in AIS scores 48 hours after surgery between the two groups（P>0.05）.The time of first exhaust,time of getting out of bed and postoperative hospitalization in TD group were all earlier than those in C group（P<0.05）,there was no significant difference in the incidence of postoperative nausea and vomiting between the two groups（P>0.05）.Conclusions:In elderly patients undergoing laparoscopic radical gastrectomy,dexmedetomidine injection by perioperative intravenous pump combined with bilateral TAP block guided by preoperative ultrasound has provided satisfactory postoperative analgesia,significantly reduced perioperative opioid use,stabilized intraoperative hemodynamics,reduced the incidence of perioperative neurocognitive disorders and inflammation,guaranteed postoperative sleep quality,shortened postoperative exhaust time,bed time and hospitalization time,and accelerated the early recovery of patients.