Suitable concentration of Ropivacaine for spinal anesthesia in super-aged( over 85-year-old) patients undergoing hip arthroplasty

Objective To observe the light specific gravity of different concentrations of Ropivacaine applied to spinal anesthesia for the clinical efficacy and safety in elderly patients over the age of 85 years undergoing hip arthroplasty. Methods According to random number table,a total of 75 elderly patients over 85 years scheduled to undergo hip surgery were divided into three groups( n = 25 / group),i. e. Group Ⅰ,Group Ⅱ and Group Ⅲgiven Ropivacaine at concetration of 0. 2%,0. 25% and 0. 3%,respectively. Ropivacaine( 2 ml) was injected into the cerebrospinal fluid smoothly at L 3- 4 gap via lumbar needle after withdrawing. The indicators,including analgesic onset time,motor block onset time,maximal pain block level,duration of anesthesia,maximal degree of motor block,and pain and sports recovery time,MAP,HR changes after Bromage score and medication,were observed. Results The difference in sensitive anesthesia onset time was not significant among the three groups. Maximal pain block level was the highest in Group Ⅲ( P 0. 05). Duration of anesthesia was higher in Group Ⅱ or Ⅲ than in Group Ⅰ( P 0. 05). Motor block onset time was earlier in Group Ⅲ than in Group Ⅱ or Ⅰ( P 0. 05). As for the number of the patient with Bromage score under 3, Group Ⅲ was more than Group Ⅱ and Group Ⅱ more than Group Ⅰ( P 0. 05). Lower extremity motor recovery time was gradually extended with the increase in the concentration of Ropivacaine,and the difference among the groups was significant( P 0. 05). Conclusion The most suitable concentration is 0. 25% of Ropivacaine with a volume of 2 ml for the elderly patients over 85-year-old undergoing hip arthroplasty. With light specific gravity,it is more effective than 0. 2% and safer than 0. 3% of isometric Ropivacaine.