Related Experiment Video
Updated: May 20, 2026
A Rat Model of Mild Intrauterine Hypoperfusion with Microcoil Stenosis
Published on: January 7, 2018
Neurodevelopmental outcome of extremely low-birth-weight infants randomly assigned to restrictive or liberal
1Department of Paediatrics, Dalhousie University, Nova Scotia, Canada. robin.whyte@dal.ca
Insights
Red blood cell transfusions for extremely low-birth-weight infants have unclear hemoglobin thresholds. Current evidence is conflicting, necessitating further research to determine optimal transfusion strategies and minimize adverse effects.
Area of Science:
- Neonatal Medicine
- Pediatric Neurology
- Hematology
Background:
- Extremely low-birth-weight infants face high risks of neurodevelopmental disability.
- Packed red blood cell transfusions are common in neonatal intensive care but optimal hemoglobin thresholds remain debated.
Purpose of the Study:
- To evaluate the impact of different hemoglobin thresholds for red blood cell transfusions on neurodevelopmental outcomes in extremely low-birth-weight infants.
- To synthesize findings from clinical trials comparing restrictive versus liberal transfusion strategies.
Main Methods:
- Review of clinical trials examining neurodevelopmental outcomes at 18-21 months corrected gestational age.
- Analysis of childhood studies (8-15 years) assessing cognitive function and brain imaging in relation to transfusion strategies.
- Consideration of methodological limitations in existing studies.
Main Results:
- Early follow-up suggested cognitive benefits favoring a liberal transfusion strategy (secondary outcome).
- Later childhood studies favored a restrictive strategy but were limited by recruitment issues.
- Serious adverse effects were reported for both strategies, indicating potential risks.
Conclusions:
- No definitive conclusion can be drawn regarding the optimal hemoglobin threshold for transfusions in extremely low-birth-weight infants.
- Current evidence is inconclusive due to conflicting results and methodological challenges in existing trials.
- Further well-designed clinical trials are required to establish best practices and ensure infant safety.
Abstract:
Surviving extremely low-birth-weight infants are at risk of severe neurodevelopmental disability. Transfusion with packed red cells is almost universal in the care of these infants, but the hemoglobin threshold at which these transfusions should be given is unclear. Different clinical trials of restrictive (low hemoglobin) versus liberal (high hemoglobin) thresholds have addressed either neurodevelopmental outcomes at 18-21 months of corrected gestational age or psychological tests and brain imaging at 8-15 years of age. Early follow-up shows differences in cognitive outcome favoring the liberal strategy, but as a post hoc secondary outcome. The childhood studies favor the restrictive strategy, but include major methodological problems of secondary recruitment. No firm conclusion can be reached, other than to report that serious adverse effects may be attributable to one or other of these strategies, that prudent practice is to remain within trial protocols, and that further redesigned clinical trials are required.
Related Concept Videos
01:19Rh Blood Group
01:52Regression Toward the Mean
02:45Blood Transfusion and Agglutination
History
The history of blood transfusion dates back to the 17th century, when early attempts were made in animals. In 1818 James Blundell, a British doctor, performed the first successful human blood transfusion. Later in 1900, Karl...