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infusion as demonstrated in Figure 3 in our article. Opioid consumption on the other hand is an indirect measure of pain intensity. We agree that PCB is associated with an opioid-sparing effect, and therefore a lower cumulative opioid intake after surgery. Our review shows significantly lower opioid consumption up to 24 h after surgery. Cumulative opioid consumption, however, provides no information on the duration of block with PCB. In fact, as a result of opioid sparing in the early postoperative period, cumulative opioid consumption would be expected to be lower in patients who have received a PCB at all time periods after surgery. To estimate the duration of block with PCB using opioid consumption, it makes more sense to analyse hourly opioid consumption or opioid consumption over short time intervals within a 48 h period. Unfortunately, these data are not available in the literature we identified for review. We therefore reiterate our finding that compared with the gold standard (postoperative opioid titration), PCB is only effective for analgesia during the first 4–8 h after surgery. This analgesic effect results in reduced opioid titration in the early postoperative period which in turn results in a lower cumulative opioid intake after surgery. This conclusion is consistent with Dr Byreddy’s findings, although we cannot confirm his observation of reduced cumulative opioid consumption beyond 24 h as a result of lack of data in the studies we analysed. Our conclusion also supports the PROSPECT guidelines on single-injection PCB for hip surgery which recommends a cautious appraisal of the risk/ benefit ratio of single-injection PCB on a case-by-case basis.