403 - Impact of pulmonary hypertension on brain injury in term encephalopathic neonates treated with hypothermia

Poster Number: 403
Publication Number: 403.135

Keira C. Kilmartin, McGill University Faculty of Medicine and Health Sciences, Hudson, PQ, Canada; Asim A. Balushi, National Heart Centre Oman, Muscat, Masqat, Oman; Emmanouil Rampakakis, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada; Pia Wintermark, McGill University Faculty of Medicine and Health Sciences, Montreal, PQ, Canada

Background: Birth asphyxia causing neonatal encephalopathy (NE) is associated with significant mortality and morbidity, even when these neonates are treated with therapeutic hypothermia (TH). These neonates often present with multi-organ failure, including hypoxic respiratory failure and persistent pulmonary hypertension (PPHN).

Objective: To investigate the effect of PPHN on outcome in neonates with NE treated with TH.

Design/Methods: This single-center retrospective study included all near-term and term neonates with NE treated with TH between 2011 and 2020. PPHN was defined as a difference between pre- and post-ductal saturation difference of greater than 10% leading to the use of inhaled nitric oxide. Adverse outcome was defined as mortality and/or brain injury on MRI.

Results: 384 newborns with NE were treated with TH. Among them, 24% had PPHN. Those with and without PPHN had similar gestational age, birth weight, and sex. Neonates with PPHN had higher fraction of inspired oxygen requirement in the first 4 days of life (P < 0.001), were more often intubated (87% vs. 58%, P < 0.001), and were more often treated for associated hypotension (73% vs. 44%, P < 0.001). They had significantly lower arterial partial pressure of oxygen (PaO2) levels during the first 2 days of life (P < 0.001), significantly higher PaO2 levels on days 3 and 4 of life (P < 0.001), and had significantly more variations of PaO2 during the first 4 days of life (P < 0.001). They died more often (22% vs. 12%, P = 0.009) and more often developed brain injury (47% vs. 37%, P = 0.02) than those without PPHN.Conclusion(s): PPHN occurred frequently in neonates with NE treated with TH. PPHN was associated with a higher incidence of adverse outcome. It remains important to avoid hyperoxemia and limit variations of PaO2 in these neonates during the first 4 days of life to potentially limit the incidence of adverse outcome.
CV Dr. Keira KilmartinCV Keira Kilmartin 12022021.pdf