Abdallah FW, et al. - Researchers performed this cohort study in ambulatory breast cancer surgery patients at Women's College Hospital between February 2014 and December 2016, to compare superficial serratus plane block to deep serratus plane block with respect to analgesic benefits. They also tested the joint hypothesis that deep serratus block is noninferior to superficial serratus block for postoperative in-hospital (pre-discharge) opioid consumption and pain severity. They found that after ambulatory breast cancer surgery, equally effective (within an acceptable margin) postoperative in-hospital analgesia was provided by deep serratus block compared to superficial serratus block.