The Ontogeny of Cerebrovascular Pressure Autoregulation in Premature Infants.
Acta Neurochir Suppl
; 122: 151-5, 2016.
Article
in En
| MEDLINE
| ID: mdl-27165897
ABSTRACT
Our objective was to quantify cerebrovascular autoregulation as a function of gestational age (GA) and across the phases of the cardiac cycle. One hundred eighty-six premature infants, with a GA range of 23-33 weeks, were monitored using umbilical artery catheters and transcranial Doppler insonation of middle cerebral artery flow velocity (FV) for 1-h sessions over the first week of life. Autoregulation was quantified as a moving correlation coefficient between systolic arterial blood pressure (ABP) and systolic FV (Sx); mean ABP and mean FV (Mx); diastolic ABP and diastolic FV (Dx). Autoregulation was compared across GAs for each aspect of the cardiac cycle. Systolic FV was pressure-passive in infants with the lowest GA, and Sx decreased with increased GA (r = -0.3; p < 0.001). By contrast, Dx was elevated in all subjects, and showed minimal change with increased GA (r = -0.06; p = 0.05). Multivariate analysis confirmed that GA (p < 0.001) and the "closing margin" (p < 0.01) were associated with Sx. Premature infants have low and almost always pressure-passive diastolic cerebral blood FV. Conversely, the regulation of systolic cerebral blood FV by autoregulation was manifested in this cohort at a GA of between 23 and 33 weeks.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Cerebrovascular Circulation
/
Middle Cerebral Artery
/
Arterial Pressure
/
Homeostasis
Limits:
Female
/
Humans
/
Male
/
Newborn
Language:
En
Journal:
Acta Neurochir Suppl
Year:
2016
Document type:
Article
Affiliation country:
United States