接受人工通气新生儿中吗啡对动脉血压的影响

Objective: To study the effects of continuous morphine infusion on arterial bl ood pressure in ventilated neonates. Design: Blinded randomised placebo controll ed trial. Setting: Level III neonatal intensive care unit in two centres. Patients: A total of 144 ventilated neonates. Inclusion criteria were postnatal age < 3 days, ventilation < 8 hours, and indwelling arterial line. Exclusion criteria were severe asphyxia, severe intraventricular haemorrhage, major congenital anomalies, neu romuscular blockers. Intervention: Arterial blood pressure was measured before t he start and during the first 48 hours of masked infusion of drug (morphine/plac ebo; 100 μg/kg+10 μg/kg/h). Outcome measures: Arterial blood pressure and blo od pressure variability. Results: There were no significant differences in overa ll mean arterial blood pressure between the morphine group (median (interquartil e range) 36 mm Hg (6) and the placebo group (38 mm Hg (6)) (P=0.11). Although si gnificantly more morphine treated patients (70%) showed hypotension than the pl acebo group (47%) (P=0.004), the use of volume expanders and vasopressor drugs was not significantly different (morphine group, 44%; placebo group, 48%; P=0. 87), indicating the limited clinical significance of this side effect. Blood pre ssure variability was not influenced by routine morphine analgesia (P=0.81) or a dditional morphine (P=0.80). Patients with and without intraventricular haemorrh age showed no differences in blood pressure (Mann-Whitney U test 1953; P=0.14) or incidence of hypotension (χ2 test 1.16; df 1; P=0.28). Conclusions: Overall arterial blood pressure, use of inotropes, and blood pressure variability were n ot influenced by morphine infusion. Therefore the clinical impact of hypotension as a side effect of low dosemorphine treatment in neonates is negligible.

随机对照试验:评价吗啡对新生儿血浆肾上腺素/去甲肾上腺素浓度的影响

Objectives: To determine the effects of continuous morphine infusion in ventil ated newborns on plasma concentrations of adrenaline (epinephrine) and noradrena line (norepinephrine)-and their relation to clinical outcome. Design: Blinded, randomised, placebo controlled trial. Setting: Level III neonatal intensive care units in two centres. Patients: A total of 126 ventilated neonates (inclusion c riteria: postnatal age < 3 days, duration of ventilation < 8 hours, indwelling a rterial catheter for clinical purposes; exclusion criteria: severe asphyxia, sev ere intraventricular haemorrhage, major congenital anomalies, neuromuscular bloc kers). Interventions: Plasma adrenaline and noradrenaline concentrations were de termined in patients during blinded morphine (n = 60) and placebo (n = 66) infus ion (100 μg/kg plus 10 μg/kg/h). Results: Plasma concentrations at baseline (n mol/l with interquartile range in parentheses) were comparable in infants treate d with morphine (adrenaline, 0.22 (0.31); noradrenaline, 2.52 (2.99)) or pla cebo (adrenaline, 0.29 (0.46); noradrenaline, 2.44 (3.14)). During infusion, median adrenaline concentrations were 0.12 (0.28) and 0.18 (0.35)-and medi an noradrenaline concentrations were 2.8 (3.7) and 3.8 (4.0) for the morphin e and placebo treated infants respectively. Multivariate analyses showed that no radrenaline (p = 0.029), but not adrenaline (p = 0.18), concentrations were si gnificantly lower in the morphine group than the placebo group. Furthermore, nor adrenaline concentrations were related to the length of stay in the neonatal int ensive care unit. Conclusions: Continuous morphine infusion significantly decrea sed plasma noradrenaline concentrations in ventilated newborns compared with pla cebo treatment. The results of this study support the idea that routine morphine administration decreases stress responses in ventilated neonates.