Altered Platelet Function in Newborns

摘要: Extract: Studies of platelet function were performed on venous blood specimens from 64 newborn infants within 0–48 h after birth. Fifty-two the studied normal, full-term average for gesta-tional age (AGA) infants, three premature AGA seven with respiratory distress syndrome (RDS), and two who had repeated apneic periods. Although it was not possible to study all variables in each groups, those studies that showed no differences results based group which an individual infant belonged. Compared 24 normal adult controls, impaired aggregation presence ADP, collagen, thrombin. The mean time required maximal thrombin adults 120, 230, 74 sec, respectively, compared values 160, 443, 158 sec (table II, figs. 2, 3, 4). percentage total 79, 91, 74% 47, 73, 47%, Infant whole platelet-rich plasma clot retraction markedly defective I). In addition, factor 3 release 10 as measured by modified Stypven time, decreased when (fig.5). Other (bleeding times, native adhesiveness, petechiometer tests) Thrombelastograms compatible hypercoagulability None clinical evidence a bleeding tendency. vitro mixing experiments suggested ADP due neither inhibitors, refractory state increased circulating levels anticoagulants, nor selected population platelets. Physiologic alterations platelets are similar functional changes observed thrombasthenia. Speculation: Transient physiologic have been described many components newborn's blood, i.e., coagulation factors, red cell enzyme changes, low immunoglobulins, altered kinin system. It is surprising, therefore, find transient deficiency well. Indeed, this hypofunction may be defense against intravascular at infant's hypercoagulable susceptible thrombotic tendencies. Whether alteration could aggravate or related cause hemorrhage severely ill remains shown.