Reduction in Intraventricular Hemorrhage by Elimination of Fluctuating Cerebral Blood-Flow Velocity in Preterm Infants with Respiratory Distress Syndrome

Abstract

In a previous study of preterm infants requiring mechanical ventilation for the respiratory distress syndrome, we demonstrated a striking association of fluctuating cerebral blood-flow velocity in the first day of life with the subsequent occurrence of intraventricular hemorrhage. Because this fluctuating pattern could be eliminated by muscle paralysis, we conducted a prospective study of preterm infants receiving mechanical ventilation for the respiratory distress syndrome in which we evaluated the effect of paralysis and this flow-velocity pattern on the incidence and severity of intraventricular hemorrhage. Twenty-four infants with the fluctuating pattern in the first hours of life were identified and randomly selected to serve as controls (10) or to be subjected to muscle paralysis (14). Intraventricular hemorrhage developed in all 10 control infants but in only 5 of the 14 infants subjected to muscle paralysis. Moreover, in 4 of the 5 paralyzed infants in whom hemorrhage developed, it did so after cessation of the paralysis. Seven of the 10 control infants had Grade III hemorrhage, the most severe variety of intraventricular hemorrhage, whereas none of the paralyzed infants had Grade III hemorrhage. We conclude that elimination of fluctuating cerebral blood-flow velocity in preterm infants with respiratory distress syndrome markedly reduces the incidence and severity of intraventricular hemorrhage.

Hypernatremia and grade III/IV intraventricular hemorrhage among extremely low birth weight infants

“…22,23 Both factors contribute to hypoperfusion and reperfusion injuries in premature babies and augment the rupture of involuting germinal matrix vessels, leading to IVH. 24,25 Fluctuations in the levels of hemoglobin were also associated with severe IVH in our study. Shaver et al showed that a lower first hematocrit level during the first 24 h of life was correlated with a higher incidence of IVH.…”

Hypercapnia during the first 3 days of life is associated with severe intraventricular hemorrhage in very low birth weight infants

“…[1][2][3] We recently observed that increasing PaCO 2 in ventilated very low birth weight (VLBW) infants during the first week of life is associated with progressively impaired cerebral autoregulation. 4 Further, hypercapnia in animals has been shown to abolish intact cerebral autoregulation.…”

Cerebral Blood Flow Velocity Changes After Bovine Natural Surfactant Instillation

“…9,[12][13][14] Using linear mixed models with random effects, individual changes in MCBFV were related to MBP changes; this finding is consistent with impaired autoregulation of cerebral circulation or a pressure-passive pattern in sick preterm infants as reported by other investigators. 4,6,13 Furthermore, we found that associated changes in MCBFV for each unit change in MBP were greater in infants who demonstrated an increase in PACO 2 . These findings suggest that increases in PACO 2 may aggravate cerebral hemodynamic alterations in those with already impaired cerebral autoregulation.…”

“…4,5 Elimination of fluctuation in cerebral blood flow has been associated with a lower incidence of IVH. 6 In an attempt to relate cerebral blood flow changes to surfactant administration, the influence of surfactant on cerebral blood flow velocity (CBFV) was studied by several investigators but with conflicting results. [7][8][9][10][11][12][13][14] Most studies involved a small number of patients and used different preparations of surfactant and different techniques of administration.…”