Perioperative management of congenital tracheal stenosis (CTS) is challenging. Objectives: We investigated the effect of closed-pediatric intensive care unit (PICU) perioperative management by pediatric intensivists, compared with open-PICU management by surgeons, on the ventilator-free days (VFD) and length of postoperative PICU stay in children with CTS. Methods: This retrospective cohort study was conducted in a PICU in Japan. Children with CTS who underwent slide tracheoplasty were grouped according to whether they were perioperatively managed in an open (January 2015 to April 2016) or a closed (May 2016 to July 2019) PICU. Data were extracted from patient medical records. Results: In total, 13 and 38 patients were included in the open- and closed-PICU groups, respectively. Compared to the open-PICU group, the closed-PICU group had shorter durations of muscle relaxant administration (median: 4 vs. 5 days; P < 0.001); earlier initiation of enteral feeding (median: postoperative day 1 vs. postoperative day 7; P < 0.001); more 28-day VFD (median: 21 vs. 20 days; P = 0.04); and shorter duration of postoperative PICU stay (median: 16 vs. 36 days; P = 0.002), but the mortality did not differ significantly (0/38 [0%] vs. 1/13 [8%]; P = 0.25). Conclusions: Closed-PICU perioperative management with pediatric intensivists’ participation significantly increased 28-day VFD and reduced the length of postoperative PICU stay in patients with CTS.