Riassunto dello studio

One hundred and fifty-nine patients scheduled for a primary total hip arthroplasty were randomized to receive spinal anesthesia with hyperbaric bupivacaine (n=54), isobaric bupivacaine (n=52), or mepivacaine (n=53). Primary outcome of interest was the percentage of patients achieving ambulation within 3-3.5 hours. Secondary outcomes of interest included the time to motor function return, initial distance ambulated, Tinetti score at first ambulation, incidence of adverse events (i.e. urinary retention, transient neurologic symptoms, dizziness), length of hospital stay, opioid consumption, pain rating, intra-operative muscle tension rating, lowest intra-operative blood pressure, and 30-day readmissions, and operative time. The results of this study demonstrated that more patients in the mepivacaine group (70% of patients) achieved ambulation within 3-3.5 hours when compared to other 2 groups (p<0.001). Moreover, patients in the mepivacaine group had a statistically significantly shorter length of hospital stay and had statistically significantly more patients discharged on the same day when compared to hyperbaric and isobaric bupivacaine groups (p<0.05 for both). The time to return to motor function was statistically significantly shorter in the mepivacaine group (109 mins) compared to the isobaric bupivacaine (148 mins). Yet, mean opioid consumption and pain was statistically significantly different across all groups (p<0.001, p=0.02; respectively) in the PACU, with mepivacaine providing the highest values. All other outcomes were not statistically significantly different across all groups (p>0.05). One patient in the mepivacaine was readmitted at 30-days post-surgery.