The Effect Of Different Concentrations Of Ropivacaine In Combination With Hydromorphone On Elderly Patients Undergoing Total Hip Arthroplasty

Objective:Compared the postoperative recovery time,anesthetic block effect and safety of an increasing concentration of ropivacaine（used for subarachnoid anesthesia）in combination with epidural administration of hydromorphone on elderly patients undergoing total hip arthroplasty.Methods:A total of 84 elderly patients undergoing total hip arthroplasty in the Second Hospital of Jilin University from June 2021 to June 2022,were randomly divided into three groups:group R_0.33（0.33%ropivacaine）,group R_0.4（0.4%ropivacaine）and group R_0.5（0.5%ropivacaine）,each group consisting of 28 cases.All patients received 10mg ropivacaine hydrochloride for subarachnoid block.Then placed an epidural catheter after injection.Hydromorphone（0.4mg）was given through an epidural catheter 30 min before the end of surgery.The observation indicators included anesthetic effect indicators（blocking success rate,onset time of sensory and motor block,the highest level of sensory block and its reaching time,improved Bromage score at 15min,also,surgeon muscle tension rating）;postoperative recovery indicators（the duration time of motor block,the first time of movement,time of hospitalization,and VAS score at 12 h post-surgery）;and safety indicators（the incidence of adverse reactions such as hypotension,nausea and vomiting）.Results:A total of 77 elderly patients were included in the analysis of this study.There were significant differences in the onset time of sensory block and motor block,the highest level of sensory block and its reaching time,the improved Bromage score at15min（P<0.05）;the onset time of motor block,the time to reach the highest level of sensory block and the improved Bromage score at 15min in group R_0.5were superior to those in group R_0.4,followed by group R_0.33,and there were statistically significant differences between subgroups.The duration of motor block,the first time of movement after operation and the time of hospitalization were significantly different among the groups（P<0.05）,multiple comparisons between groups showed that there were significant differences between group R_0.5and the other two groups,while there was no significant difference between group R_0.33and group R_0.4;the speed of postoperative recovery in group R_0.5was slower than that in groups R_0.33and R_0.4.There were significant differences in hypotension,nausea and vomiting between group R_0.5and groups R_0.33and R_0.4（P<0.05）,while there was no significant difference between group R_0.33and group R_0.4;the safety of group R_0.5was lower than that of the other two groups.There was no significant difference among the three groups in terms of general information,blocking success rate,surgeon muscle tension rating,postoperative 12h VAS score,and the incidence of bradycardia and oxygen desaturation.Conclusion:0.4%ropivacaine hydrochloride（10mg）used for subarachnoid anesthesia combined with 0.4mg epidural hydromorphone for elderly patients undergoing total hip replacement,the recovery speed and safety are better than 0.5%ropivacaine hydrochloride combined with hydromorphone,the anesthesia block effect is better than 0.33%ropivacaine hydrochloride combined with hydromorphone.