TY - JOUR
T1 - Diffusion tensor imaging in extremely low birth weight infants managed with hypercapnic vs. normocapnic ventilation
AU - Ou, Xiawei
AU - Glasier, Charles M.
AU - Ramakrishnaiah, Raghu H.
AU - Angtuaco, Teresita L.
AU - Mulkey, Sarah B.
AU - Ding, Zhaohua
AU - Kaiser, Jeffrey R.
N1 - Funding Information:
Acknowledgments Ou was supported by the Children’s University Medical Group (CUMG) at UAMS and the Thrasher Research Fund. Mulkey was supported by the Center for Translational Neuroscience award from the National Institutes of Health (P20 GM103425). Kaiser was supported by the National Institutes of Health (1K23NS43185, RR20146 and 1R01NS060674) and the UAMS Translational Research Institute (1UL1RR029884). The technical assistance of Natalie C. Sikes, Melanie J. Mason and Nicole A. Johnson and the support of the UAMS and ACH neonatologists, NICU nurses, respiratory therapists, and MRI technologists and nurses are gratefully appreciated. Ou was additionally mentored by Thomas Badger, PhD, and Michael Borrelli, PhD, for this project.
PY - 2014/8
Y1 - 2014/8
N2 - Background: Permissive hypercapnia is a ventilatory strategy used to prevent lung injury in ventilated extremely low birth weight (ELBW, birth weight ≤1,000 g) infants. However, there is retrospective evidence showing that high CO2 is associated with brain injury. Objective: The objective of this study was to compare brain white matter development at term-equivalent age in ELBW infants randomized to hypercapnic vs. normocapnic ventilation during the first week of life and in healthy non-ventilated term newborns. Materials and methods: Twenty-two ELBW infants from a randomized controlled trial were included in this study; 11 received hypercapnic (transcutaneous PCO2 [tcPCO2] 50-60 mmHg) ventilation and 11 normocapnic (tcPCO 2 35-45 mmHg) ventilation during the first week of life while still intubated. In addition, ten term healthy newborns served as controls. Magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) was performed at term-equivalent age for the ELBW infants and at approximately 2 weeks of age for the control infants. White matter injury on conventional MRI was graded in the ELBW and control infants using a scoring system adopted from literature. Tract-based spatial statistics (TBSS) was used to evaluate for differences in DTI measured fractional anisotropy (FA, spatially normalized to a customized template) among the ELBW and term control infants. Results: Conventional MRI white matter scores were not different (7.3±1.7 vs. 6.9±1.4, P=0.65) between the hypercapnic and normocapnic ELBW infants. TBSS analysis did not show significant differences (P<0.05, corrected) between the two ELBW infant groups, although before multiple comparisons correction, hypercapnic infants had many regions with lower FA and no regions with higher FA (P<0.05, uncorrected) compared to normocapnic infants. When compared to the control infants, normocapnic ELBW infants had a few small regions with significantly lower FA, while hypercapnic ELBW infants had more widespread regions with significantly lower FA (P<0.05, fully corrected for multiple comparisons). Conclusions: Normocapnic ventilation vs. permissive hypercapnia may be associated with improved white matter development at term-equivalent age in ELBW infants. This effect, however, was small and was not apparent on conventional MRI. Further research is needed using larger sample sizes to assess if permissive hypercapnic ventilation in ELBW infants is associated with worse white matter development.
AB - Background: Permissive hypercapnia is a ventilatory strategy used to prevent lung injury in ventilated extremely low birth weight (ELBW, birth weight ≤1,000 g) infants. However, there is retrospective evidence showing that high CO2 is associated with brain injury. Objective: The objective of this study was to compare brain white matter development at term-equivalent age in ELBW infants randomized to hypercapnic vs. normocapnic ventilation during the first week of life and in healthy non-ventilated term newborns. Materials and methods: Twenty-two ELBW infants from a randomized controlled trial were included in this study; 11 received hypercapnic (transcutaneous PCO2 [tcPCO2] 50-60 mmHg) ventilation and 11 normocapnic (tcPCO 2 35-45 mmHg) ventilation during the first week of life while still intubated. In addition, ten term healthy newborns served as controls. Magnetic resonance imaging (MRI) with diffusion tensor imaging (DTI) was performed at term-equivalent age for the ELBW infants and at approximately 2 weeks of age for the control infants. White matter injury on conventional MRI was graded in the ELBW and control infants using a scoring system adopted from literature. Tract-based spatial statistics (TBSS) was used to evaluate for differences in DTI measured fractional anisotropy (FA, spatially normalized to a customized template) among the ELBW and term control infants. Results: Conventional MRI white matter scores were not different (7.3±1.7 vs. 6.9±1.4, P=0.65) between the hypercapnic and normocapnic ELBW infants. TBSS analysis did not show significant differences (P<0.05, corrected) between the two ELBW infant groups, although before multiple comparisons correction, hypercapnic infants had many regions with lower FA and no regions with higher FA (P<0.05, uncorrected) compared to normocapnic infants. When compared to the control infants, normocapnic ELBW infants had a few small regions with significantly lower FA, while hypercapnic ELBW infants had more widespread regions with significantly lower FA (P<0.05, fully corrected for multiple comparisons). Conclusions: Normocapnic ventilation vs. permissive hypercapnia may be associated with improved white matter development at term-equivalent age in ELBW infants. This effect, however, was small and was not apparent on conventional MRI. Further research is needed using larger sample sizes to assess if permissive hypercapnic ventilation in ELBW infants is associated with worse white matter development.
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U2 - 10.1007/s00247-014-2946-8
DO - 10.1007/s00247-014-2946-8
M3 - Article
C2 - 24671721
AN - SCOPUS:84905023196
SN - 0301-0449
VL - 44
SP - 980
EP - 986
JO - Pediatric Radiology
JF - Pediatric Radiology
IS - 8
ER -