Curves of ropivacaine concentration-time in plasma after multineedle subcutaneous injection of RODD.
The results represent the mean±SD (RODD, n = 6~8; RHI, n = 3). After subcutaneous injection of RODD or RHI in healthy subjects’ abdomens, venous blood was taken and centrifuged, and the upper layer of plasma was treated with protein precipitation. The content of ropivacaine in plasma was measured at different time points. The concentrations of ropivacaine at 0.5, 1, 1.5 and 2 h after administration are shown in A. The results indicated that ropivacaine could be quickly released from the RODD and enter the blood circulation. The ropivacaine concentration-time curves from 0–72 h are shown in B. Compared with RHI, the concentration of ropivacaine from RODD was higher and showed a bimodal phenomenon.