Survival and unique clinical practices of extremely preterm infants born at 22-23 weeks' gestation in Japan: a national survey.

Objectives: To investigate prognosis and clinical practices of infants born at 22-23 weeks' gestational age (wkGA) in Japan.

Design: A national institutional-level electronic questionnaire surveys performed in September 2021.

Setting: All perinatal centres across Japan.

Patients: Infants born at 22-23 wkGA in 2018-2020.

Main outcome measures: Proportion of active resuscitation and survival at neonatal intensive care unit (NICU) discharge, and various clinical practices.

Results: In total, 255 of 295 NICUs (86%) responded. Among them, 145 took care of infants born at 22-23 wkGA and answered the questions regarding their outcomes and care. In most NICUs (129 of 145 (89%)), infants born at 22⁺⁰ wkGA can be actively resuscitated. In almost half of the NICUs (79 of 145 (54%)), infants born at ≥22⁺⁰ wkGA were always actively resuscitated. Among 341 and 757 infants born alive at 22 and 23 wkGA, respectively, 85% (291 of 341) and 98% (745 of 757) received active resuscitation after birth. Among infants actively resuscitated at birth, 63% (183 of 291) and 80% (594 of 745) of infants born at 22 and 23 wkGA survived, respectively. The survey revealed unique clinical management for these infants in Japan, including delivery with caul in caesarean section, cut-cord milking after clamping cord, immediate intubation at birth, hydrocortisone use for chronic lung disease, analgesia/sedation use for infants on mechanical ventilation, routine echocardiography and brain ultrasound, probiotics administration, routine glycerin enema and skin dressing to prevent pressure ulcers.

Conclusions: Many 22-23 wkGA infants were actively resuscitated in Japan and had a high survival rate. Various unique clinical practices were highlighted.