ĐẶC ĐIỂM THIẾU MÁU Ở TRẺ SINH NON DƯỚI 32 TUẦN TẠI BỆNH VIỆN NHI ĐỒNG 2

Abstract

Background: Preterm infants born before 32 weeks’ gestation are at increased risk of anemia due to limited iron stores resulting from reduced maternal supply during the third trimester, low endogenous erythropoietin levels, infections, and comorbidities requiring frequent phlebotomy. Early identification of risk factors and clinical manifestations enables timely and effective intervention to prevent severe anemia-related complications. Objective: To describe the clinical characteristics of preterm infants < 32 weeks’ gestation diagnosed with anemia at Children's Hospital 2. Methods: This case series study included preterm infants born under 32 weeks of gestation. Results: Thirty-two preterm infants < 32 weeks admitted to Children’s Hospital 2 between January 1, 2022, and July 31, 2024, were diagnosed with anemia. The mean gestational age was 28.2 ± 1.5 weeks; 11/32 (34.4%) were born at < 28 weeks. The mean birth weight was 1203.4 ± 286.8 grams. The mean phlebotomy blood loss before the diagnosis of anemia (Hct < 35%) was 9.67 ± 4.12 ml/kg in infants < 28 weeks and 7.17 ± 5.03 ml/kg in those born between 28–32 weeks (p = 0.17). Clinically, one-third of the cases presented pathologic apnea; less than 10% showed pallor, and none of them had a heart rate > 180 beats per minute. 12/32 infants (37.5%) required packed red blood cell transfusions, with transfusion rates of 63.64% in the extremely preterm group versus 23.81% in the very preterm group (p = 0.027). The mean length of hospital stay was 71.3 ± 14.6 days in the transfusion group versus 37.1 ± 16.7 days in the non-transfusion group (p < 0.01). Conclusion:  In preterm infants < 32 weeks, anemia clinically presents as pathologic apnea in one-third of cases, and most commonly occurs within the first 1–2 weeks of life. The blood transfusion rate in extremely preterm infants is 2,67 times higher than in very preterm infants, and transfusion is associated with prolonged hospital stays.