Riassunto dello studio

A total of nine studies with 739 patients undergoing a total knee arthroplasty (TKA) were included in this meta-analysis comparing continuous-injection adductor canal blockade (ACB) and to single-injection ACB for post-operative pain control. The primary outcome of interest was pain on a visual analogue scale (VAS) at rest or during activity. Secondary outcomes of interest included cumulative opioid consumption, incidence of vomiting and nausea, rescue analgesia consumption, and length of stay in the hospital. VAS pain scores at rest were pooled at 4, 8, 12, 24, and 48 hours post-operation, whereas pain during mobility was pooled at 24 and 28 hours post-operation. Pooled results demonstrated that VAS pain scores at rest were statistically significantly in favour of the continuous ACB group compared to the single-injection ACB group, up until 24 hours post-operation. VAS pain scores during movement were statistically significantly different in favour of the continuous ACB group at 48 hours (p<0.00001), but not at 24 hours (p=0.10). Pooled cumulative consumption opioid within 48 hours (p=0.07), incidence of nausea and vomiting (p=0.42), and length of stay (p=0.09) were not statistically significantly different between the two groups. Finally, rescue analgesia was statistically significantly lowered in the continuous ACB group compared to the single-injection ACB group (p=0.03).