Analysis of acylcarnitine profiles in umbilical cord blood and during the early neonatal period by electrospray ionization tandem mass spectrometry

Acylcarnitine profiling by electrospray ionization tandem mass spectrometry (ESI-MS/MS) is a potent tool for the diagnosis and screening of fatty acid oxidation and organic acid disorders. Few studies have analyzed free carnitine and acylcarnitines in dried blood spots (DBS) of umbilical cord blood (CB) and the postnatal changes in the concentrations of these analytes. We have investigated these metabolites in healthy exclusively breastfed neonates and examined possible effects of birth weight and gestational age. DBS of CB were collected from 162 adequate for gestational age neonates. Paired DBS of heel-prick blood were collected 4-8 days after birth from 106 of these neonates, the majority exclusively breastfed. Methanol extracts of DBS with deuterium-labeled internal standards were derivatized before analysis by ESI-MS/MS. Most of the analytes were measured using a full-scan method. The levels of the major long-chain acylcarnitines, palmitoylcarnitine, stearoylcarnitine, and oleoylcarnitine, increased by 27, 12, and 109%, respectively, in the first week of life. Free carnitine and acetylcarnitine had a modest increase: 8 and 11%, respectively. Propionylcarnitine presented a different behavior, decreasing 9% during the period. The correlations between birth weight or gestational age and the concentrations of the analytes in DBS were weak (r £ 0.20) or nonsignificant. Adaptation to breast milk as the sole source of nutrients can explain the increase of these metabolites along the early neonatal period. Acylcarnitine profiling in CB should have a role in the early detection of metabolic disorders in high-risk neonates.

Verapamil no tratamento da emergencia hipertensiva. / Verapamil in the treatment of hypertensive emergency

Quarenta e cinco pacientes com emergencia hipertensiva foram tratados com verapamil, na dose de 5,48 a 6,68 micrograma/min, administrado por EV em gotejamento continuo de uma solucao contendo 50 mg da droga diluidos em 200 ml de soro glicosado a 5%. Nao se observou alteracao substancial da frequencia cardiaca apos a administracao do farmaco (reducao de 9,7%). Seus efeitos na pressao arterial foram observados ja a partir de 2 min de infusao, com reducao da PA media de 169 mais ou menos 22 para 120 mais ou menos 16 mm/Hg (30%) em 2 hs. Nao houve diferenca entre a reducao da pressao arterial sistolica e diastolica. O controle imediato da pressao arterial, a obtencao de niveis tensionais adequados e a quase ausencia de efeitos colaterais justificam o uso do verapamil para o tratamento das emergencias hipertensivas