Heliox non-invasive ventilation for preventing extubation failure in preterm infants.

OBJECTIVES: Our aim was to assess whether non-invasive ventilation with heliox may decrease the incidence of extubation failure in preterm infants with RDS. METHODS: Infants <29 weeks of gestation were treated immediately after extubation with heliox combined with nasal continuous airway pressure (Hx-NCPAP) or bilevel NCPAP (Hx-BiPAP) for 24 h, while infants in the control groups were treated with conventional NCPAP or BiPAP. The primary endpoint was the comparison of the extubation failure rate in the two groups, where failure was defined as the need for MV during the 24 h following extubation. RESULTS: Eighteen infants were assigned to the heliox group and 18 to the control group. The extubation failure rate was similar (p = 0.249) in the heliox (n = 6; 33%) and in the control group (n = 9; 50%), but required mean airway pressure (MAP: 4.0+1.0 vs. 4.8+1.2 cm H2O; p = 0.037) and PaCO2 (39+8 mmHg vs. 52+7 mmHg; p < 0.001) at 24 h of treatment were lower in the heliox group. CONCLUSIONS: Non-invasive ventilation with heliox was not effective in decreasing extubation failure in preterm infants with RDS, but did improve their respiratory function. Our findings might support the planning of large randomized controlled studies to evaluate the effectiveness of heliox non-invasive ventilation for decreasing extubation failure in premature infants.

Lutein and zeaxanthin supplementation in preterm infants to prevent retinopathy of prematurity: a randomized controlled study.

OBJECTIVES: Lutein and its isomer zeaxanthin (L/Z) function in the eye as antioxidant agents and blue-light filters. Our aim was to evaluate whether their administration could help decrease the occurrence of retinopathy of prematurity (ROP) in preterm infants. METHODS: Infants with gestational age ≤32 weeks were randomly assigned to receive a daily dose of L/Z (0.14 + 0.006 mg) or placebo until discharge. RESULTS: ROP occurrence was similar in the L/Z (11/58; 19%) and placebo (15/56; 27%) groups, as the occurrence of ROP at each stage and the need of eye surgery. CONCLUSION: L/Z supplementation was ineffective in preventing ROP in preterm infants and did not affect the outcome at discharge of our patients.

Phenobarbital for neonatal seizures in hypoxic ischemic encephalopathy: a pharmacokinetic study during whole body hypothermia.

PURPOSE: Therapeutic hypothermia has recently been introduced to treat term newborns with hypoxic-ischemic encephalopathy, of whom more than half have seizures. Phenobarbital is widely used to treat neonatal seizures, but it is unknown whether its pharmacokinetics is affected by hypothermia. We evaluated the influence of hypothermia on phenobarbital pharmacokinetics in asphyxiated newborns. METHODS: Nineteen term asphyxiated newborns treated with mild whole body hypothermia, started within 6 h after birth and protracted for 72 h, received phenobarbital for clinical seizures. Treatment schedule consisted of a loading dose of 20 mg/kg, titrated to response, up to a maximum dose of 40 mg/kg, followed by a maintenance dose of 2.5 or 1.5 mg/kg every 12 h. Phenobarbital concentrations were measured on 28 dried blood spots in each newborn. KEY FINDINGS: Eighteen newborns showed plasma concentrations within the reference range after receiving a loading dose of 20 mg/kg. In the remaining newborn, who had received a loading dose of 35 mg/kg, phenobarbital concentrations exceeded the upper reference limit. Phenobarbital concentrations reached a virtual steady state in all newborns. Pharmacokinetic parameters were then calculated. Minimum and maximum concentration (24.7 ± 8.8 and 30.63 ± 10.3 mg/L), average plasma concentration (27.37 ± 9.4 mg/L), and half-life (173.9 ± 62.5 h) were considerably higher than reported in literature for normothermic newborns. Pharmacokinetic parameters did not differ significantly between infants receiving different maintenance doses. SIGNIFICANCE: Phenobarbital administered to newborns under whole body hypothermia results in higher plasma concentrations and longer half-lives than expected in normothermic newborns.

Oral clonidine provocative test in the diagnosis of growth hormone deficiency in childhood: should we make the timing uniform?

INTRODUCTION: Oral clonidine is one of the most frequent drugs used for the diagnosis of growth hormone deficiency (GHD), but the duration of the test, depending on which European centres use it, is not uniform and can vary from 120 to 150 min or even 180 min. SUBJECTS AND METHODS: To standardize this test, evaluating the possibility to shorten it to 90 min, we investigated the response of GH to the oral clonidine test in 291 children evaluated for short stature (height <-2 SD). Of these, 164 were diagnosed as idiopathic short stature (ISS) and 127 as GHD. In these patients, we calculated: (1) the frequency distribution of the GH peaks to clonidine in GHD and in ISS at various times; (2) the percentage of GH peaks to clonidine before and after 90 min in all and in ISS children; (3) the percentage of the first GH value >or=10 ng/ml before 90 min and after 90 min in ISS. RESULTS: GH peak distribution varied between 30 and 180 min, even though the vast majority of peaks occurred between 30 and 60 min. There was no significant difference (p > 0.05) in the peak distribution between ISS and GHD children. The percentages of GH peaks within 90 min were 92.1% in all children and 95.7% in ISS. If considering the first value of GH >or=10 ng/ml this last percentage reaches 96.3%. CONCLUSION: Our study suggests that the oral clonidine test can be administered for only 90 min without significantly changing its validity. This test should be standardized at 90 min in European protocols just as in those currently used in the USA in order to reduce the discomfort of patients and the cost of this diagnostic procedure.