Determinação dos valores hematológicos e das concentrações séricas de ferro e ferritina em sangue de cordão umbilical de recém-nascidos de termo e pré-termo no Hospital Israelita Albert Einstein de São Paulo

ABSTRACT

Several hematologic values (hemoglobin, hematocrit, reticulocyte count, mean concentration of hemoglobin, mean corpuscular concentration) and serum concentration of iron and ferritin were obtained from umbilical cord blood of 32 term newborn babies and 30 preterm newborn babies born at Hospital Albert Einstein. All babies were healthy, with no clinical problems at delivery or in the few hours after birth. Blood was obtained by needle puncture on umbilical vein at least 5 minutes after the placenta was detached from endometrium, and sent to Central Laboratory to be analised. The hematologic values were more elevated in the group of term babies in comparison with the group of preterm (p 0,05). Serum concentrations of iron and ferritin were more elevated in the group of term babies in comparison with the group of preterm babies (p 0,05). There was no difference statistically significant in the reticulocyte count of both groups. Adjusting a model of multiple logistic regression, the hematocrit had a positive predictive value for preterm babies, and an inversely proportional relationship between hematocrit values and gestacional age was observed.

RESUMO

Determinaram-se os valores hematológicos (Hb, Ht, VCM, HCM, CHCM, reticulócitos) e as concentrações séricas de ferro e ferritina no sangue de cordão umbilical de recém-nascidos (RN) no Hospital Albert Einstein. A amostra continha 32 RN de termo (T) e 30 RN pré-termo (PT). Os RN apresentavam-se clinicamente sadios, sendo excluídos os que apresentaram intercorrências clínicas ou no momento do parto. O sangue foi colhido por punção da veia umbilical até 5 minutos após a dequitação e encaminhado ao laboratório de patologia clínica para processamento laboratorial. Os valores hematológicos encontram-se mais elevados no grupo de RNT em relação ao grupo de RNPT (p 0,05). Ajustando-se um modelo de regressão logística múltipla, o Ht tem valor preditivo para a prematuridade, observando-se uma relação inversamente proporcional entre o valor do Ht e a idade gestacional.