Association between Multi-Organ Involvement and Brain Injury in Cooled Newborns: A Statistical Approach

In the event of fetal hypoxia-ischemia, circulation to the brain and central organs is thought to be preserved. The objective of the study was to explore the relationship between the presence of brain injury on MRI and multi-organ involvement, as reflected in routinely collected laboratory (lab) values in babies who have undergone therapeutic hypothermia (TH) after hypoxic-ischemic encephalopathy (HIE).

Peak and trough values, and age at peak/trough, were obtained for 10 lab markers collected for clinical care, representing hematopoiesis, coagulation, inflammation, hepatic, and renal function, from 71 consecutively recruited newborns from four tertiary neonatal centers undergoing TH. Cerebral MR images obtained as part of clinical care were assessed by two raters with expertise, in a blinded fashion.

There was no significant association between the presence of cerebral injury on MRI and systems involvement in newborns who have undergone TH. However, the peak/trough platelet ratio was significantly associated with cerebral injury. Also, the peak platelet, lymphocyte, and urea counts occurred significantly later in babies with substantial brain injury compared to those without.

Using a statistical approach, we demonstrate that there is no clear relationship between multi-organ involvement and cerebral injury in babies with HIE who have undergone TH. We infer that babies may have cerebral injury in the absence of involvement of other organ systems. The platelet count ratio as an independent biomarker of cerebral injury in this group requires further investigation. Reference ranges of lab values for term newborns undergoing TH are provided.