Perioperative Analgesia Evaluation Of Different Doses Of Dexamethasone For Ultrasound-guided Ropivacaine Iliac Fascia Block

Objective:To investigate the blocking effect of different doses of dexamethasone combined with ropivacaine in iliac fascia space block（FICB）after total hip replacement（THA）.Methods:According to the random number table,83 patients with THA were divided into observation group 1（n=27）,observation group 2（n=28）and control group（n=28）.All patients were FICB guided by ultrasound.Observation group 1,observation group 2 and control group were given 0.25%ropivacaine 100 mg combined with dexamethasone 5 mg,10 mg and 0 mg,respectively.The duration of surgery and VAS scores at rest and exercise at 4（T₄）,8（T₈）,12(T₁₂),24(T₂₄),36(T₃₆)and 48(T₄₈)hours after local anesthetic injection（hereinafter referred to as post-injection）were recorded.Quadriceps muscle strength score at 8,12,24,36,48 hours after post-injection,analgesic pump pressing times and remedial analgesia times within 48 hours after post-injection.Results:1)There weren’t significant differences in operation duration,VAS scores at T₄,T₈and T₄₈between the three groups.at T₁₂,T₂₄and T₃₆,the VAS scores of observation group1 and 2 during rest and exercise were lower than those of control group（P<0.05）,and there wasn’t significant difference in VAS scores of observation group 1 and 2 during rest and exercise.2)There wasn’t significant difference in muscle strength grade 1～5 score composition among 3 groups at T₈,T₁₂,T₂₄,T₃₆and T₄₈（P>0.05）.3)In terms of the ratio of 2 or more times of analgesic pump pressing and 1 or more times of remedial analgesia within 48 hours after operation,the observation group 1 and observation group 2 were lower than the control group（P<0.05）,but there wasn’t statistical significance between observation group 1 and observation group 2（P>0.05）.Conclusion:The FICB analgesic effect of ropivacaine was enhanced by dexamethasone 5 mg and dexamethasone 10 mg,but the inhibitory effect of quadriceps muscle strength wasn’t increased.