Fluorescence in situ hybridization and chromosome studies after transfusion in newborns: is a waiting period necessary?

BACKGROUND: Delaying chromosome studies after transfusion is common practice in many neonatal intensive care units (NICUs). Yet, no evidence exists to support this practice. PURPOSE: To investigate the effects of filtration and irradiation on chromosome detection, and to evaluate donor chromosome interference after transfusion. METHODS: Packed red blood cells (PRBCs) were evaluated by fluorescence in situ hybridization (FISH) and chromosome analyses. To evaluate donor leukocyte survival, blood was collected from female neonates who received male-donated PRBCs. RESULTS: Irradiated, leukodepleted blood had no Y chromosome detection by FISH. Irradiated, microaggregate filtered blood had Y chromosome detection in all samples by FISH but no metaphase growth. No donor chromosomes were detected in neonates after transfusion. CONCLUSIONS: Delaying chromosome or FISH analysis in transfused neonates who have received irradiated blood is unnecessary.

Inhaled nitric oxide in the treatment of moderate persistent pulmonary hypertension of the newborn: a randomized controlled, multicenter trial.

OBJECTIVE: Inhaled nitric oxide (iNO) improves oxygenation and reduces the need for extracorporeal membrane oxygenation in infants with severe persistent pulmonary hypertension of the newborn (PPHN). The effectiveness of iNO in the treatment of moderate PPHN has not been adequately defined. We therefore conducted a randomized, prospective multicenter study to assess whether iNO in patients with moderate PPHN would improve arterial p(a)O(2), prevent progression to severe PPHN, and improve outcomes. METHODS: Infants > or = 34 weeks gestation with moderate pulmonary hypertension (alveolar-arterial oxygen gradient (AaDO(2)) 500-599 Torr) were randomly assigned to continue standard medical therapy (control group) or standard medical therapy plus iNO (iNO group). For each patient in the iNO group, iNO concentration was increased in steps of 10-20 ppm every 30 minutes until there was no further improvement in arterial p(a)O(2). This concentration of iNO was then maintained while all other ventilatory support, including inspired oxygen concentration, was weaned according to a predefined protocol. RESULTS: In all, 27 of 40 control patients (58%) compared to six of 40 infants (15%) in the iNO group failed assigned therapy and developed severe PPHN (p<0.0005). Arterial p(a)O(2) improved from 112+/-48 to 133+/-100 (p=0.132) in control infants compared to an increase from 101+/-29 to 208+/-118 (p<0.0005) in iNO-treated patients. For the first 36 hours after study, entry AaDO(2) levels and ventilatory support were significantly lower in iNO-treated infants compared to control patients. CONCLUSION: In patients with moderate PPHN, treatment with iNO improves arterial p(a)O(2), reduces the amount of ventilatory support needed, and prevents progression to severe PPHN.