Myocardial Adaptation to Anemia and Red Blood Cell Transfusion in Premature Infants Requiring Ventilation Support in the 1st Postnatal Week

Abstract

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. Objectives: 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.

Fetal myocardial peak systolic strain before and after intrauterine red blood cell transfusion – a tissue Doppler imaging study

“…Our results are supported by the fi ndings of the conventional vascular Doppler studies in anemic neonates: the more severe anemia is, the higher is the myocardial contractility [6] .…”

“…Changes in V max and amount of blood fl ow have been proven in anemia [4,8,9,13,16,19,20,24,30] . The additional acute massive volume burden of IUT to the fetal heart is supposed to further change the hemodynamic state [6,22,30] .…”

Systolic Right Ventricular Function in Preterm and Term Neonates: Reference Values of the Tricuspid Annular Plane Systolic Excursion (TAPSE) in 258 Patients and Calculation of Z-Score Values

“…This maintained RV performance has been described in both healthy neonates [4] and infants with respiratory distress syndrome [5] . In preterm infants, anemia and blood cell transfusion have been shown to have an influence on ventricular function [36] . Subhedar and Shaw [37] demonstrated that premature infants with bronchopulmonary dysplasia (BPD) had higher echocardiographically-derived pulmonary artery pressures than did premature infants without BPD.…”

Correlation Between Cardiac Tissue Doppler and Peripheral Vascular Doppler in the Anemic Fetus – An Additional Method to Determine the Transfusion Threshold?

“…If our measurements had comprised not only ventricular and annular but also atrial ROIs, the relationship between the atrial myocardial function and the flow pattern of the DV speculated on here probably would have become obvious. The longitudinal PS reveals a significantly negative correlation with the PI in the UA in the right ventricle, being in accordance with an increased contractility in anemia [3,17]. The RV seems to compensate for stress.…”