Placental pathology as a marker of brain injury in infants with hypoxic ischemic encephalopathy.

BACKGROUND

Hypoxic Ischemic Encephalopathy (HIE) can lead to devastating consequences for the affected infant. Although therapeutic cooling benefits infants with moderate and severe HIE, differentiating mild from moderate-severe HIE may be challenging. The placenta reflects the fetal intrauterine environment and may reveal underlying processes that affect brain injury.

AIM: To describe placental histopathology using the Amsterdam Placental Workshop Group Criteria in different grades of HIE.

STUDY

DESIGN

Retrospective cohort.

SUBJECTS: Infants admitted to a tertiary care neonatal intensive care unit with a diagnosis of HIE between 2011 and 2016.

OUTCOME MEASURE: Maternal and neonatal clinical variables and placental histopathology using the Amsterdam Placental Workshop Group Criteria were compared between mild and moderate-severe HIE. Mann-Whitney or t-test or ꭓ2 were performed for bivariate associations as appropriate. To explain the relationship between placental pathology and severity of HIE odds ratios (ORs) and 95 % confidence intervals (CIs) were calculated using logistic regression models.

RESULTS

Of the 73 infants in the study, 23 had mild and 50 moderate-sever HIE. There was no difference in maternal and neonatal characteristics except for sentinel events which were higher in the moderate- severe group. On placental histopathology, acute inflammation, including fetal inflammatory reaction (FIR) were significantly higher in the moderate-severe group. After adjusting for confounders, FIR remained significantly associated with moderate-severe HIE, ORs 6.29, 95 % CI 1.5-25.

CONCLUSION

Our study demonstrates FIR in the placenta is associated with severity of HIE.