Objective To assess the clinical effects of spinal anesthesia with low blocking level for perianal surgery

and to explore the optimal dose and injection speed of low dose and slow administration under spinal anesthesia. Methods A total of 65 patients who planned to undergo perianal surgery in our hospital from August 2016 to March 2017 were selected.The patients were divided into the observation group and the control group randomly. For the observation group

the bupivacaine is 0.6 mL with slowly injection rate of 0.1 mL/5s.For the control group

the bupivacaine is 1.5 mL with injection rate of 0.1 mL/s.Observed the blood pressure and heart rates before anesthesia

10 minutes and 30 minutes after anesthesia. Recorded the blocking level

movement capability of hip

visual analogue scale (VAS)

surgeon and patient satisfaction

time of pain relief

time of postoperative motion recovery

and complication of the the two groups after spinal anesthesia. Results In the observation group

the blocking level

time of pain relief

time of postoperative motion recovery were obviously lower than those of the control group (P<0.05); and the movement capability of hip was obviously better than the control group (P<0.05). There was no siginificant difference in satisfaction of surgeon and patient

VAS

and complication after spinal anesthesia between the two groups. Conclusion Low dose and slow drug injection speed in lumbar anesthesia can obtain a lower blocking level than conventional lumbar anesthesia

and it may have a better clinical effect in perianal surgery.