Early systemic hypotension and vasopressor support in low birth weight infants: impact on neurodevelopment.
BACKGROUND
The duration and severity of systemic hypotension have been related with altered neurodevelopment. Cerebral circulation is pressure-passive in low birth weight infants with early systemic hypotension who receive cardiovascular support. The treatment of early systemic hypotension is controversial, because it has been associated with short-term and long-term morbidity in retrospective studies. However, there has been no prospective information on cardiovascular support for hypotension and morbidity.


OBJECTIVE
Our goal for this prospective study was to evaluate the effect on neurodevelopment resulting from the use of vasopressors/inotropes for early systemic hypotension.


METHODS
Low birth weight infants with early systemic hypotension (<24 hours of life; study group) were assigned randomly to receive dopamine (2.5-10 microg/kg per minute) or epinephrine (0.125-0.5 microg/kg per minute) in progressively larger doses until target blood pressure was attained (treatment-success subgroup). Hemodynamically stable patients who did not receive cardiovascular support were the control group. Outcome measures were serial cranial ultrasound up to 40 weeks, structured neurologic evaluation (every 3 months), and neurodevelopmental test at 2 to 3 years of age.


RESULTS
One hundred thirty patients were included (study = 60; treatment success = 38; controls = 70). Study-group patients had lower birth weight, gestational age, and 5-minute Apgar score, higher rates of premature rupture of membranes, need for cardiorespiratory resuscitation at birth, and sickness shortly after birth than the control group. The patients in the study group also had significantly higher serum troponin I levels at birth. Initial cranial ultrasound findings did not differ between groups, but the final cranial ultrasounds revealed higher rates of severe periventricular hemorrhage in the study group and higher rates of normal cranial ultrasounds in the control group. Only the latter remained when the treatment-success subgroup and control group were compared. Multivariate analysis did not detect any association between final cranial ultrasounds and the use of vasopressors/inotropes. Sixteen infants died and 103 were followed up (90% survival rate). No differences between groups were found in the rates of abnormal neurologic status, developmental delay, or combined adverse outcome (death or cerebral palsy or severe neurodevelopmental delay).


CONCLUSIONS
Cautious use of cardiovascular support to treat early systemic hypotension in low birth weight infants seems to be safe. The question of whether raising systemic blood pressure to within a normal range will improve outcome should be examined by using appropriate study designs.
Pellicer
Adelina
A
La Paz University Hospital, Department of Neonatology, Paseo de Castellana 261, E-28046 Madrid, Spain. apellicer.hulp@salud.madrid.org
Bravo
María del Carmen
MC
Madero
Rosario
R
Salas
Sofía
S
Quero
José
J
Cabañas
Fernando
F
D001034:Apgar Score; D001724:Birth Weight; D002316:Cardiotonic Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D002657:Child Development / Q000502:physiology*; D004298:Dopamine / Q000008:administration & dosage / Q000627:therapeutic use*; D004837:Epinephrine / Q000008:administration & dosage / Q000627:therapeutic use*; D005074:Evoked Potentials, Visual; D005865:Gestational Age; D006801:Humans; D007022:Hypotension / Q000628:therapy*; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D015999:Multivariate Analysis; D009460:Neurologic Examination; D011446:Prospective Studies; D019210:Troponin I / Q000097:blood; D014662:Vasoconstrictor Agents / Q000627:therapeutic use*
D002316:Cardiotonic Agents; D019210:Troponin I; D014662:Vasoconstrictor Agents; D004298:Dopamine; D004837:Epinephrine