Blood pressure in low birth weight infants in the first eleven weeks of life.

The enhanced diagnostic significance of blood pressure during the earliest period of human life is already well known. The present study, performed in the Special Care Unit for Preterm Infants, First City Hospital, Sofia Bulgaria, concerns a longitudinal follow-up of blood pressure values of 400 newborn low birth weight infants who were appropriate and small for their gestation age during the first eleven weeks of life. A steady increase in blood pressure was observed, which advanced with maturity and age of the preterm infants, particularly for systolic blood pressure. Some changes in blood pressure also progressed after intravenous infusion of bioproducts such as plasma and packed erythrocyte cells. There is a relation between systolic blood pressure prior to and after transfusion. The information available so far in almost all literature sources covers the first days and weeks. Here, the first data concerning the initial eleven weeks of human life are presented.