Elevated Diastolic Closing Margin Is Associated with Intraventricular Hemorrhage in Premature Infants

• Published in: The Journal of pediatrics Vol. 174; pp. 52 - 56
• Main Authors: Rhee, Christopher J., MD, Kaiser, Jeffrey R., MD, MA, Rios, Danielle R., MD, Kibler, Kathleen K., CCP, Easley, R. Blaine, MD, Andropoulos, Dean B., MD, Czosnyka, Marek, PhD, Smielewski, Peter, PhD, Varsos, Georgios V., PhD, Rusin, Craig G., PhD, Gauss, C. Heath, MS, Williams, D. Keith, PhD, MPH, Brady, Ken M., MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.07.2016
• Subjects: arterial blood pressure; Blood Flow Velocity - physiology; Blood Pressure - physiology; cerebral blood flow; Cerebral Hemorrhage - etiology; Cerebral Hemorrhage - physiopathology; Cohort Studies; critical closing pressure; Diastole; Female; Humans; Infant, Newborn; Infant, Premature; Infant, Premature, Diseases - etiology; Infant, Premature, Diseases - physiopathology; Male; Middle Cerebral Artery - physiology; Pediatrics; Respiration, Artificial; Umbilical Arteries - physiology; CBF; NICU; Intraventricular hemorrhage; Diastolic closing margin; Cerebral blood flow velocity; Estimated gestational age; ABP; DCM; CBFV; arterial blood pressure; critical closing pressure; Neonatal intensive care unit; cerebral blood flow; IVH; CrCP; EGA
• ISSN: 0022-3476; 1097-6833
• DOI: 10.1016/j.jpeds.2016.03.066

Objective To determine whether the diastolic closing margin (DCM), defined as diastolic blood pressure minus critical closing pressure, is associated with the development of early severe intraventricular hemorrhage (IVH). Study design A reanalysis of prospectively collected data was conducted. Premature infants (gestational age 23-31 weeks) receiving mechanical ventilation (n = 185) had ∼1-hour continuous recordings of umbilical arterial blood pressure, middle cerebral artery cerebral blood flow velocity, and PaCO2 during the first week of life. Models using multivariate generalized linear regression and purposeful selection were used to determine associations with severe IVH. Results Severe IVH (grades 3-4) was observed in 14.6% of the infants. Irrespective of the model used, Apgar score at 5 minutes and DCM were significantly associated with severe IVH. A clinically relevant 5-mm Hg increase in DCM was associated with a 1.83- to 1.89-fold increased odds of developing severe IVH. Conclusion Elevated DCM was associated with severe IVH, consistent with previous animal data showing that IVH is associated with hyperperfusion. Measurement of DCM may be more useful than blood pressure in defining cerebral perfusion in premature infants.