Precision of cerebral oxygenation and hemoglobin concentration measurements in neonates measured by near-infrared spectroscopy.

BACKGROUND AND AIM: One source of error with near-infrared spectroscopy (NIRS) is the assumption that the measured tissue is optically homogeneous. This is not always the case. Our aim is to assess the impact of tissue homogeneity (TH) on the precision of NIRS measurements in neonates. METHODS: On 36 term and 27 preterm neonates at least five 1-min measurements are performed on each subject using the OxiplexTS. The sensor position is slightly changed before each measurement while assessing TH. The precision for cerebral tissue oxygenation saturation (StO(2)) and total hemoglobin concentration (tHb) are calculated by repeated measures analysis of variance. RESULTS: The mean StO(2) is not significantly different between term and preterm infants. The mean tHb is significantly lower in preterm infants (p < 0.01). With increasing TH, the precision of StO(2) increase from 5.6 to 4.6% for preterm and from 11.0 to 2.0% for term infants; the precision of tHb increases from 10.1 to 7.5µM for preterm and from 16.4 to 3.5 µM for term infants. The precision for StO(2) is higher in term than in preterm infants. The precision for tHb shows no significant difference between the two groups. CONCLUSIONS: The precision of NIRS measurements correlates with tissue homogeneity.

An approach to using recombinant erythropoietin for neuroprotection in very preterm infants.

OBJECTIVE: Erythropoietin has been shown to be protective against hypoxic-ischemic and inflammatory injuries in cell culture, animal models of brain injury, and clinical trials of adult humans. The rationale for our study was that early administration of high-dose recombinant human erythropoietin may reduce perinatal brain injury (intraventricular hemorrhage and periventricular leukomalacia) in very preterm infants and improve neurodevelopmental outcome. We investigated whether administration of high-dose recombinant human erythropoietin to very preterm infants shortly after birth and subsequently during the first 2 days is safe in terms of short-term outcome. METHODS: This was a randomized, double-masked, single-center trial with a 2:1 allocation in favor of recombinant human erythropoietin. Preterm infants (gestational age: 24 to 31 weeks) were given recombinant human erythropoietin or NaCl 0.9% intravenously 3, 12 to 18, and 36 to 42 hours after birth. RESULTS: The percentage of infants who survived without brain injury or retinopathy was 53% in the recombinant human erythropoietin group and 60% in the placebo group. There were no relevant differences regarding short-term outcomes such as intraventricular hemorrhage, retinopathy, sepsis, necrotizing enterocolitis, and bronchopulmonary dysplasia. For 5 infants who were in the recombinant human erythropoietin group and had a gestational age of <26 weeks, withdrawal of intensive care was decided (3 of 5 with severe bilateral intraventricular hemorrhage, 2 of 5 with pulmonary insufficiency); no infant of the control group died. Recombinant human erythropoietin treatment did not result in significant differences in blood pressure, cerebral oxygenation, hemoglobin, leukocyte, and platelet count. CONCLUSIONS: No significant adverse effects of early high-dose recombinant human erythropoietin treatment in very preterm infants were identified. These results enable us to embark on a large multicenter trial with the aim of determining whether early high-dose administration of recombinant human erythropoietin to very preterm infants improves neurodevelopmental outcome at 24 months' and 5 years' corrected age.

Antibiotic resistance patterns among respiratory pathogens at a German university children's hospital over a period of 10 years.

UNLABELLED: Growing antimicrobial resistance among Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis is raising major concern worldwide. Strains of S. pneumoniae, H. influenzae and M. catarrhalis isolated from children with respiratory tract as well as invasive infection in a South-Western region of Germany between 1993 and 2002 were tested for susceptibility to common antibiotics including penicillins, cephalosporins and macrolides. A total of 2,362 S. pneumoniae, 2,501 H. influenzae, and 1,982 M. catarrhalis isolates were tested. Only two S. pneumoniae strains were found to be highly resistant to penicillin. The overall rate of intermediate resistance to penicillin was 3.5%. There was a significant increase in erythromycin resistance from 5% in 1993 to 12.2% in 2002 (P=0.001). No increase in ampicillin resistance was observed for H. influenzae over time. The rate of cefaclor resistance, however, increased from 4.5% to 11.8% (P<0.0001). Furthermore, a massive increase in erythromycin resistance from 26% to 40% was observed (P<0.0001). The vast majority of M. catarrhalis isolates were beta-lactamase positive, the minimal inhibitory concentration to ampicillin, however, exceeded only in 3% of all strains the cut-off of 1.5 mg/l. The erythromycin resistance rate of M. catarrhalis was 0.3%. CONCLUSION: There is still a low rate of penicillin/ampicillin resistance in S. pneumoniae, and H. influenzae, but an alarming increase in resistance to erythromycin, and in H. influenzae a significant increase in cefaclor resistance was observed over the 10-year period in South-Western Germany.

Association between resistance to erythromycin and the presence of the fibronectin binding protein F1 gene, prtF1, in Streptococcus pyogenes isolates from German pediatric patients.

A total of 301 German pediatric group A streptococcus isolates were screened for the presence of macrolide resistance and the fibronectin binding protein F1 gene (prtF1) encoding an adhesin and cell invasiveness protein. The prtF1 gene was present significantly more often among macrolide-resistant isolates. The majority of these were not clonally related.