157 Neonatal Polycythemia: Hemodilution With Saline vs Serum. Effects on Hematocrit, Blood- And Plasma Volume

Abstract

We studied the possibility to improve lung distensibility by SI during the first hours of a e. Preterm newborn lambs (123-133 days of gestational age, n=78) were used. Initially all lambs were mechanically ventilated with 100% 02, ~e a k inspiratory pressure (PIP) was adjusted for paCO2. For SI he ventilator was disconnected and the lungs were inflated during five seconds at a PIP of 25 or 35 cmH20 with a mixture of 5% C02 and 95% 02. Each inflation was followed by positive end expiratory pressure of 5 cmH20 for 5 seconds. This procedure was repeated three times. SI was applied in three groups: 1) within 15 minutes after birth, 2) within 15 minutes after birth and repeated each hour for 3 hours 3) at 4 hours of age. Two control groups (4 and 5) were formed, 4) as group 1, except that during disconnection the lungs were inflated,at the same pressure as for SI but with ,short inspiratory time, 5) lambs were ventilated widout any manipulation. Blood gas samples were taken every 30 minutes. Compliance (Cl) was calculated from the injected volume of air per kg wet body weight needed to obtain a pressure of 20 cmH20.Results (mean+SEM) at 3 hours after birth: 56 University of Lihurg, Rpts. of Neonatology, Physiclogy* and Biophysics**, Maastricht, The Netherlands. Cerebral blood flow velocity (CsFV) is decreased in plycythemic newborns and it normalizes after PPET. To study the influence of plycythemia on peripheral blood flow velocity (PBEV) we measured PBFV and CBFV in 17 plycythemic newborns.Nine normocythemic infants served as controls.Blood flow velocity was measured prior to and at 3 and 24 hrs after PPET in the study group and at 3 and 24 hrs after birth in the controls. Flow velocities were recorded with a 5MHz bidirectional continuous wave velocimeter. Hct decreased from 72.524.0% to 59.021.5% after PPET. Peripheral mean flow velocity ( W C o ) in polycythemic newborns did not differ from controls. Cerebral mean flow velocity was decreased in plycythemic newborns and normalized after PPET. MEAN RUV vnaCITYcontrol group P &fore PPET after P P m P TPP (g/I) serum 6025 * 5525 5727 saline 5654 *** 4825+ 55+7 **'p<0.001 *'<0.01 *<0.05 (paired t-test);# p=0.05 serumvs saline (unpaired t-test) lsovolumetric HD with saline resulted i n a smaller (p-zO.05) decrease i n Hct than HD with serum and was not associated with an isovolemic substitution of withdrawn blood. out with a decrease of BV at the end and 4h after HD, because saline let the intravascular space already during HD. Conclusion: Rapid loss from the intravascular volume and the decrease of blood volume make saline less effective for HD i n neona:al polycythemia and possibly for volume substitution i n general. We investigated the relation between obesity and lipid and apoprotein levels in 286 children, 6-14 years aged, 133 males and 153 females (16.5% with obesity). Weight, height and skinfolds were calculated for each child. Sg rum samples were collected after 12 hours fast; total cholesterol (TC), triglycerides (TG) and HDL cholesterol (HDLC) were de termin...