Tau/P-Tau and Neurocognitive Outcomes in Children

This proposed studies have two specific aims:

1. To investigate the relationship between pre-operative or postoperative blood levels of
Tau or P-Tau and neurocognitive outcomes. The working hypothesis is that pre- and
postoperative blood Tau/P-Tau levels are higher in participants who develop
neurocognitive impairment than those in the participants who do not develop it. The
investigators will perform neurocognitive test before the surgery and then at 12 months
after the surgery. The investigators will collect pre-operative and postoperative blood
and measure Tau/P-Tau levels in the blood. Finally, the association of the changes in
the Tau/P-Tau levels and neurocognitive scores will be assessed. More importantly, this
Aim will establish an eligible: recruit ratio, retention rates, safety of the protocol,
and power calculation, which will provide crucial information to guide better design of
future R01 study.

2. To perform the feasibility studies of measuring Tau or P-Tau in urine, feces and saliva
of the participants. The working hypothesis is that Tau/P-Tau in urine, feces or saliva
of children can be measured. The investigators will use the nanobeam to measure
Tau/P-Tau levels before and after the surgery. The investigators will then determine
whether urine, feces and saliva can be used for the future studies to develop Tau/P-Tau
as the biomarker of anesthesia/surgery-associated neurocognitive impairment in children.

Inclusion Criteria:

1. between age 3 and 5 at the time of the first neurocognitive test;

2. scheduled for surgery under general anesthesia

Exclusion Criteria:

1. gestational age less than 36 weeks;

2. congenital heart disease that has required surgery or will require surgery or that
requires ongoing pharmacotherapy;

3. known chromosomal abnormality or any other known acquired or congenital abnormalities
which are likely to affect neurodevelopment;

4. known neurological injury such as cystic periventricular leukomalacia or grade 3 or 4
intra-ventricular hemorrhage (+/- post hemorrhage ventricular dilatation);

5. children for whom follow-up would be difficult for geographic or psychosocial reasons;

6. non-native English speaker (both child and parents);

7. severe visual or auditory disorder.