Papers of the Week

The common technique using a basal infusion for an ambulatory continuous peripheral nerve blocks frequently results in exhaustion of the local anesthetic reservoir prior to resolution of surgical pain. We sought to improve and prolong analgesia by delaying initiation using an integrated timer and delivering a lower hourly volume of local anesthetic as automated boluses. We hypothesized that, compared with a traditional continuous infusion, ropivacaine administered with automated boluses at a lower dose and 5-hour delay would (1) provide at least noninferior analgesia [difference in average pain no greater than 1.7 points] while both techniques were functioning [average pain score day after surgery]; and, (2) result in a longer duration [dual primary outcomes].