# General Anesthesia During Early Childhood and Brain Development

> **NIH NIH R01** · UNIVERSITY OF IOWA · 2020 · $602,796

## Abstract

PROJECT SUMMARY/ABSTRACT
 Substantial data indicate that general anesthesia (GA) causes neurotoxicity and long-term deficits in
learning and memory in young animals. Millions of young human children have GA annually. This is of great
public health concern given the possibility that early GA could cause abnormalities in brain and cognitive
development that might have lifelong consequences. Although there is great concern that findings from animal
studies may apply to humans, limited evidence exists concerning the possible adverse effects on brain and
cognitive development of early GA in humans. Studies using neuroimaging techniques are especially limited.
Our objective in this proposal is to understand the consequences of GA during early childhood on subsequent
brain structure, brain function, and cognition by comparing adolescents with GA during early childhood to
otherwise similar control subjects without GA. We will evaluate the effects of GA on magnetic resonance
imaging measures of brain tissue volume and composition, white matter integrity, regional brain activity
during long-term and working memory tasks, and resting state functional connectivity, as well as cognitive test
performance and academic achievement. Our hypotheses, based on our preliminary data, are that early GA will
be associated with lower white matter volumes and diminished white matter integrity, memory-related changes
in brain activity during long-term and working memory tasks, impaired visual long-term memory recognition,
and a higher frequency of very low achievement test scores. The proposed research additionally aims to
compare GA occurring at varying ages within the range of birth to 3 years, and accompanying high vs. low
invasive procedures. We will focus primarily on children without significant central nervous system problems
or potential risk factors that might constitute confounding factors. We additionally hypothesize that to
whatever extent the hypotheses stated above are confirmed, the observed effects will be smaller for first GA
exposure at older ages, e.g., smaller effects from exposure at 3 years relative to near birth; and be comparable
for high vs. low invasive procedures, when other factors such as GA duration and gender are controlled. We
also hypothesize that any such effects will increase with increasing GA duration. We will additionally explore
influences of comorbidity (i.e., premature birth) and regional anesthesia on consequences of GA. The findings
could address potential mechanisms of the brain effects of GA found in animal studies, such as apoptosis of
oligodendrocytes and neurons and/or other neurotoxicity that occur during critical developmental periods. The
proposed research will help fill a critical gap in knowledge concerning the consequences of GA during early
childhood on brain and cognitive development, and provide information about its risks that might change best
practices for clinical care of children who have GA.

## Key facts

- **NIH application ID:** 9922136
- **Project number:** 5R01HD089420-03
- **Recipient organization:** UNIVERSITY OF IOWA
- **Principal Investigator:** ROBERT I BLOCK
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $602,796
- **Award type:** 5
- **Project period:** 2018-07-01 → 2024-03-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9922136

## Citation

> US National Institutes of Health, RePORTER application 9922136, General Anesthesia During Early Childhood and Brain Development (5R01HD089420-03). Retrieved via AI Analytics 2026-05-22 from https://api.ai-analytics.org/grant/nih/9922136. Licensed CC0.

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