Neurocardiovascular coupling: revealing insight in perioperative neonatal physiology

BACKGROUND The effect of peri-operative management on
the neonatal brain is largely unknown. Triggers for perioper-
ative brain injury might be revealed by studying changes in
neonatal physiology peri-operatively.
OBJECTIVE To study neonatal pathophysiology and cere-
bral blood flow regulation peri-operatively using the neuro-
cardiovascular graph.
DESIGN Observational, prospective cohort study on peri-
operative neuromonitoring. Neonates were included be-
tween July 2018 and April 2020.
SETTING Multicentre study in two high-volume tertiary uni-
versity hospitals.
PATIENTS Neonates with congenital diaphragmatic hernia
were eligible if they received surgical treatment within the
first 28 days of life. Exclusion criteria were major cardiac or
chromosomal anomalies, or syndromes associated with al-
tered cerebral perfusion or major neurodevelopmental im-
pairment. The neonates were stratified into different groups
by type of peri-operative management.
INTERVENTION Each patient was monitored using near-
infrared spectroscopy and EEG in addition to the routine
peri-operative monitoring. Neurocardiovascular graphs were
computed off-line.
MAIN OUTCOME MEASURES The primary endpoint was
the difference in neurocardiovascular graph connectivity in
the groups over time.
RESULTS Thirty-six patients were included. The intraoper-
ative graph connectivity decreased in all patients operated
upon in the operation room (OR) with sevoflurane-based
anaesthesia (P < 0.001) but remained stable in all patients
operated upon in the neonatal intensive care unit (NICU) with
midazolam-based anaesthesia. Thoracoscopic surgery in the
OR was associated with the largest median connectivity
reduction (0.33 to 0.12, P < 0.001) and a loss of baroreflex
and neurovascular coupling. During open surgery in the OR,
all regulation mechanisms remained intact. Open surgery in
the NICU was associated with the highest neurovascular
coupling values.
CONCLUSION Neurocardiovascular graphs provided more
insight into the effect of the peri-operative management on
the pathophysiology of neonates undergoing surgery. The
neonate’s clinical condition as well as the surgical and the
anaesthesiological approach affected the neonatal physiolo-
gy and CBF regulation mechanisms at different levels.
TRIAL REGISTRATION NL6972, URL: https://www.trialre-
gister.nl/trial/6972.