Commonly-used versus less commonly-used methods in the loss of resistance technique for identification of the epidural space: A systematic review and meta-analysis of randomized controlled trials

STUDY OBJECTIVE: To summarize the efficacy of less-commonly used modern methods (e.g. epidrum, lidocaine, acoustic device, Macintosh balloon) compared to more commonly-used methods (i.e. air, saline, both) in the loss of resistance technique for identification of the epidural space. DESIGN: A systematic review.