Myocardial adaptation to anemia and red blood cell transfusion in premature infants requiring ventilation support in the 1st postnatal week.
BACKGROUND
Although transfusion practice in very premature infants is becoming more restrictive, little is known about myocardial adaptation to anemia during the 1st postnatal week.


OBJECTIVE
To determine the central hemodynamic effects of anemia and red blood cell transfusion in very preterm infants undergoing intensive care.


METHODS
Twenty-nine neonates of less than 30 weeks gestational age were treated for respiratory distress syndrome, following a strict protocol. Echocardiographies were performed at the 4th and 6th postnatal days, which corresponded to, respectively, just before and 48 h after an erythrocyte transfusion of 15 ml/kg in the 12 anemic infants.


RESULTS
Anemic infants had increased stroke volume [2.1 (1.8-2.3) vs. 1.5 (1.3-1.6) ml/kg] and left ventricular (LV) output [312 (271-345) vs. 206 (177-240) ml/min/kg]. The relationship of the heart rate-corrected velocity of circumferential fiber shortening to LV end-systolic meridional wall stress indicated a higher contractile state in the anemic infants, with a higher y-intercept (p = 0.03) and a steeper slope (p = 0.05) of the regression line than in the nonanemic patients. Posttransfusion, the stroke volume, LV output, shortening fraction, and contractile state decreased to the values observed in the nonanemic infants.


CONCLUSIONS
Myocardial contractility was a major component of the circulatory adjustments in the anemic premature infants requiring ventilation support in the early neonatal period. Changes in LV performance associated with anemia were reversed by transfusion with no detrimental effect on right ventricular function, LV preload or the respiratory status of these patients.
Cambonie
Gilles
G
Neonatal Intensive Care Unit, Arnaud de Villeneuve Hospital, University Hospital Centre of Montpellier, Montpellier, France. g-cambonie@chu-montpellier.fr
Matecki
Stephan
S
Milési
Christophe
C
Voisin
Michel
M
Guillaumont
Sophie
S
Picaud
Jean-Charles
JC
D000222:Adaptation, Physiological; D000740:Anemia / Q000150:complications / Q000503:physiopathology / Q000628:therapy*; D004562:Electrocardiography; D017707:Erythrocyte Transfusion; D019317:Evidence-Based Medicine; D005260:Female; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D015278:Intensive Care Units, Pediatric; D008297:Male; D009200:Myocardial Contraction / Q000502:physiology*; D012121:Respiration, Artificial; D012127:Respiratory Distress Syndrome, Newborn / Q000150:complications / Q000503:physiopathology / Q000628:therapy*
D006454:Hemoglobins