Effect Of Dexmedetomidine For Postoperative Pain Management In Elderly Patients Suffered Femoral Head Replacement

Objectives To investigate the effects of dexmedetomidine combined with sufentanil for postoperative pain management in elderly patients suffered femoral head replacement(FHR).Methods Elderly patients(American Society of Anesthesiologists class ? ~ ?)scheduled for elective FHR under spinal anesthesia between January and August in 2016 were randomly allocated into four groups(n=40each).Group C(control group): PCIA with sufentanil and tropisetron;group D1,D2,D3(experimental groups): PCIA with three different doses of dexmedetomidine in addition.All enrolled patients undertook spinal anesthesia for surgery.The pain scores at rest and with movement were evaluated with a visual analogue scale(VAS)and Ramsay sedation score were recorded at the 4,8 and 24 h after surgery.The rescue drug administration and PONV development were recorded.Postoperative hypotension,bradycardia,respirator depression were also recorded.All enrolled patients were followed up at one week after surgery using Confusion assessment method(CAM)to detected delirium development within a week.The time of PCIA application were recorded.IL-6 concentration was recorded at the time before anesthesia and 4h after surgery.Results Compared with group C,VAS at rest and with movement were lower at 4,8 and 24 h after surgery in group D1,D2,D3(P<0.05).There was no difference in Ramsay scores among the four groups(P>0.05).Rescue drug administration and PONV development were rarer in group D1,D2 and D3 compared with group C(P<0.05).Fewer patients develop delirium in experimental groups than those in control group,but there was no statistical significance(P>0.05).The duration of PCIA application was shorter in group C than those in group D1,D2 and D3(P<0.05).There was with the best analgesia effects in group D3,with the dosage of dexmedetomidine IV infusion rate as 0.042 mcg/kg/h.There were no statistical significance on IL-6 concentrations at the time before anesthesia(P>0.05),but IL-6 concentrations were lower in all three experimental groups than that in control group(P<0.05).Conclusions 1.Dexmedetomidine may enhance the analgesia effect of sufentanil PCIA and reduce the PONV development in elderly patients suffered from FHR.2.Dexmedetomidine as an adjunctive drug of sufentanil PCIA may depress the inflammation of elderly patients suffered from FHR.3.The optimal dosage of dexmedetomidine as an adjunctive for PCIA is approximately 0.04 mcg/kg/h.