[Infant mortality in Germany (2008-2012)--lower in the former German Democratic Republic?]. / Säuglingssterblichkeit in Deutschland (2008-2012)--niedriger im Osten?

BACKGROUND: German infant mortality is ranked near the median of European countries. In Germany infant mortality is significantly higher in the German Federal Republic compared with the former German Democratic Republic. This is often used as reason for a call for structural requirements and minimum caseload for the care for very low birth weight infants. METHOD: Neonatal and infant mortality were calculated for the 16 German federal states with data from the German statistical federal office for the years 2008-2012. RESULTS: Considerable variations were found for the neonatal (1.34-3.61‰, total Germany 2.31‰) and the infant (2.38-5.20‰, 3.47‰) mortality. The rate of stillborn infants was 3.56‰. A lower neonatal mortality in the former German Democratic Republic (1.62‰ vs. 2.44‰, p<0.0001, Chi-squared test) could not be confirmed for preterm infants with birth weight less than 1 500 g. In the former German Democratic Republic stillbirth was significantly more frequent in preterm infants with birth weight 500-999 g (p<0.0001). Combined stillbirth and neonatal mortality showed no difference between the German Federal Republic and former German Democratic Republic (5.45‰ and 5.29‰, respectively, n.s.; infants less than 500 g birth weight were excluded). The average number of preterm infants per perinatal centre and federal state had no influence on state specific neonatal mortality. CONCLUSION: If stillborn infants were accounted for no difference was found between the German Federal Republic and the former German Democratic Republic regarding mortality. Comparing infant mortality of different countries has to account for stillborn infants. Considerable variation of neonatal mortality is persisting throughout Germany despite structural requirements and introduction of a minimum caseload since 2005. A lower infant mortality in the former German Democratic Republic and implications drawn from are not supported by the presented nationwide data from the German statistical federal office.

Calcium and phosphor intake in preterm infants: sensitivity and specifity of 6-hour urine samples to detect deficiency.

Aim of the present study was to test whether six-hour (6 h) urine specimens predict the 24-hour (24 h) mineral homeostasis in individual infants born preterm. Urinary Calcium (Ca) and Phosphate (P) concentrations were studied in 60 stable infants; gestational age 34 (25-42) weeks. In 58 infants four 6 h urine specimens and in 2 infants all spot urine specimens obtained within 24 h were analyzed. In 39 infants born preterm coefficients of variation were 0.42 (SD 0.26) and 0.41 (SD 0.26) for Ca and P measurements in the four 6 h urine specimens obtained within 24 h, respectively, The mineral homeostasis of the infants was defined as Ca or P surplus homeostasis if the 24 h urinary concentrations were ≥1 mmol/l. The sensitivity, specificity, and PPV of a 6 h urinary specimen to predict Ca deficiency homeostasis (24 h urinary Ca <1 mmol/l) were 0.93 (0.77-0.98; 95%CI), 0.72 (0.43-0.90) and 0.90 (0.74-0.96). The sensitivity, specificity and PPV for urinary P were 0.8 (0.38-0.96), 0.97 (0.85-0.995), and 0.8 (0.38-0.96). In conclusion, in infants born preterm on regular 3 or 4 h feedings, 6 h urine sampling is sufficiently precise for prediction of Ca and P mineral deficiency homeostasis (PPV 0.92 and 0.83). However, measurements at regular intervals (twice weekly) are recommended not to miss any infant in mineral deficiency homeostasis.

[Prevention of bone mineral deficiency in premature infants: review of the literature with focus on monitoring of urinary calcium and phosphate]. / Knochenmineralmangel bei Frühgeborenen: Prävention mittels Urinmonitoring von Kalzium und Phosphat.

BACKGROUND: Bone mineral deficiency of prematurity (BMDoP) is caused by the lack of simultaneous availability of calcium (Ca) and anorganic phosphate (P) during rapid skeletal growth. METHODS: Review of the literature on the prevention of BMDoP, with specific attention to the limitations of the monitoring of urinary calcium and phosphate concentrations. RESULTS: Intrauterine bone mineral accretion (BMA) can be achieved in preterm infants if urinary concentrations of Ca and P continuously show that the supplementation with these ions slightly exceeds the actual need. An individually adjusted supplementation with Ca and P appears rational because both growth velocity and enteral Ca absorption are highly variable and determine the need for enteral Ca and P administration. If, however, urinary concentrations of Ca and P are used to determine whether Ca and P supplementation is adequate, mechanisms affecting the urinary excretion of these ions other than nutrition have to be taken into account. Specifically, methylxanthines and diuretics increase the renal Ca losses, and the renal P threshold may be lowered in premature infants. A positive effect of physical activity on BMA has been shown in several studies. CONCLUSIONS: An individualized Ca and P supplementation in preterm infants aiming for supplementation in a slight excess of the actual need and guided by urinary Ca and P concentrations appears able to prevent BMDoP. Monitoring of urinary Ca and P concentrations needs to take into account non-nutritional factors affecting these concentrations. BMA may further be improved by physical activity.

[Current outcome quality in the care of preterm infants with birth weight less than 1 500 g as a basis for regionalisation of risk pregnancies]. / Aktuelle Ergebnisqualität der Versorgung von Frühgeborenen <1 500 g Geburtsgewicht als Grundlage für eine Regionalisierung der Risikogeburten.

BACKGROUND: For preterm infants an association between patient volume and mortality has been described. METHODS: Outcome variables were evaluated for 28 hospitals in Baden-Württemberg for the years 2004-2008. Hospitals with high patient volume were compared to hospitals with a lower patient volume. RESULTS: Outcomes for 1 164 infants in 2008 and for 4 775 infants in 2004-2008 were analysed. In 2008, mortality of preterm infants less than 32 weeks gestational age (GA) was 9.2% (n=402) in the 5 major hospitals compared to 6.5% (n=520) in the other hospitals (combined mortality 7.7%, n. s., chi-square test). In the years 2004-2008, mortality showed a greater variation in hospitals with a patient volume below 50 and mean mortality was 21.1% higher for infants less than 500 g BW. Hospitals with a patient volume >or= 50 had a lower mortality for infants with BW below 500 g and between 500 g and 749 g (18% and 11%, chi-square test: p<0.05 and <0.01, respectively). For preterm infants with GA below 24 weeks and between 24 and 25 weeks, patient volume and mortality were negatively correlated (p<0.01 and <0.0001, respectively). For infants with a BW >or= 750 g or a GA >or= 26 weeks patient volume had no effect on outcome. CONCLUSION: Regionalisation of preterm infants with BW less than 750 g and a GA less than 26 weeks may contribute to reduce mortality. Infants with BW >or= 750 g and a GA >or= 26 weeks may not benefit from indirect quality indicators such as patient volume.

[Thoracic alterations after surgical closure of the ductus arteriosus botallo in preterm infants]. / Thoraxveränderungen nach operativem Ductus-arteriosus-Botallo-Verschluss bei Frühgeborenen.

BACKGROUND: Left-sided thoracotomy for ligation of patent ductus arteriosus (PDA) dissects the musculus latissimus dorsi and notches a small part of the musculus trapezius. After ductal closure the 4 (th) and 5 (th) rib are adapted. This follow-up study investigated if mid- or long-term consequences on the thorax occur after this procedure. PATIENTS AND METHODS: Status of the thoracic scar, functionality of the shoulder and presence of scapulata alata or scoliosis was evaluated at median age of 6 years (range: 2.9-11.9) in 57 pre-term infants (30 male; gestational age 26 weeks (24-32); birth weight 805 g (450-2140)). RESULTS: Scoliosis was diagnosed in 1 patient (=1.8%) with Rubinstein-Taybi syndrome. The length of the thoracic scar (13.8 cm; 9.4-25.5) correlated with the patient's age (r=0.61; p=0.001). The scar was relocatable except for one case. The distance of the ventral end of the scar to the nipple was 2 cm or less in 22% of the female patients. None of the patients showed impaired function of the shoulder. Scapula alata was found in 16 (28%) patients. CONCLUSION: Thoracotomy for PDA ligation was not associated with an increased risk for scoliosis or disturbed function of the shoulder. One quarter of all infants developed scapula alata which meant an aesthetic issue for some parents.

[Regionalisation of preterm births in county districts? Yes we can!]. / Regionalisierung bei Frühgeburtsbestrebungen im ländlichen Raum? Yes we can!

BACKGROUND: In preterm labour prenatal transfer of the pregnant woman to perinatal centres or subspecialty hospitals is thought to improve outcome of very low birth weight infants (VLBW). Can preterm labour diagnosed early enough? MATERIAL: Records of the neonatal referral centre at the Ulm University Hospital (1974-2003) and of the regional neonatal working group (1986-2003). RESULTS: The rate of inborn VLBW infants increased from 40 to 95-100%. CONCLUSION: It was possible to diagnose preterm labour early enough for prenatal transfer. DISCUSSION: On the strength of past experience it may be assumed that the obstetrician's or institution's willingness to transfer mothers before delivery was the critical factor of the nearly complete regionalization.

Effect of oestradiol and progesterone replacement on bronchopulmonary dysplasia in extremely preterm infants.

OBJECTIVE: To study whether postnatal replacement of oestradiol and progesterone may help to prevent bronchopulmonary dysplasia (BPD). METHODS: This randomised placebo-controlled double-blind study enrolled 83 infants of <29 weeks gestational age and 1000 g birth weight requiring mechanical ventilation within 12 h after birth. Oestradiol (2.5 mg/kg/day) and progesterone (22.5 mg/kg/day) were given by continuous intravenous infusion of a standard lipid emulsion (15 ml/kg/day) in the replacement group (ESTRA-PRO). The placebo group received the same lipid emulsion without oestradiol or progesterone. A replacement period of at least 2 weeks but not >4 weeks was strived for and defined as "according to protocol". The primary outcome variable was the incidence of BPD or death. RESULTS: The median birth weight was 670 g (min-max 400-990 g) and the gestational age 25 weeks (23.1-28.1 weeks). The incidence of BPD or death was 48% in the placebo group and 44% in the ESTRA-PRO group (p = 0.38, one-sided testing, intention to treat analysis). In infants treated according to protocol, 32% (9 of 28) in the placebo group and 14% (3 of 21) in the ESTRA-PRO group developed BPD (p = 0.08). CONCLUSION: Replacement of oestradiol and progesterone was not effective for prevention of BPD or death in extremely preterm born infants. Better-powered trials are needed to evaluate this new approach.

Skeletal growth in fetal rats. Effects of glucose and amino acids.

The modified hyperglycemia-hyperinsulinism hypothesis, which characterizes intrauterine growth of diabetic pregnancy, was studied in fetal rats. From day 19 to day 21 postconception, pregnant rats were constantly infused with saline, amino acids, or glucose. In the fetus, serum somatomedin activity was determined, with the porcine bioassay and the incorporation of 3H-thymidine into rib cartilage and isolated chondrocytes in vivo in response to serum from normal maternal or fetal rats. In comparison with control fetuses, body weights were decreased in glucose-exposed fetuses (4.66 +/- 0.25 versus 3.75 +/- 0.99, N = 121; P less than 0.001), and increased (4.87 +/- 0.57, N = 105; P less than 0.05) in amino acid-exposed fetuses. Serum somatomedin activity (U/ml) was higher in glucose-treated (0.79 +/- 0.40, N = 11; P less than 0.05) and amino acid-treated animals (0.90 +/- 0.16, N = 10; P less than 0.001) than in controls (0.55 +/- 0.04, N = 13). In vivo labeling with thymidine resulted in a higher radioactivity of cartilage in small fetuses compared with large fetuses when the dams had been infused with saline (r = -0.531, N = 56; P less than 0.001) or amino acids (r = -0.292, N = 52; P less than 0.01). Opposite results were obtained in hyperglycemic animals (r = 0.542, N = 54; P less than 0.001). When isolated chondrocytes were incubated with serum from normal fetal rats, the incorporation of thymidine was about 10 times higher into cells from small fetuses than from large fetuses, irrespective of the infusion regimen.(ABSTRACT TRUNCATED AT 250 WORDS)

Ventilation strategies and outcome in randomised trials of high frequency ventilation.

OBJECTIVE: Randomised controlled trials comparing elective use of high frequency ventilation (HFV) with conventional mechanical ventilation (CMV) in preterm infants have yielded conflicting results. We hypothesised that the variability of results may be explained by differences in study design, ventilation strategies, delay in initiation of HFV, and use of permissive hypercapnia. METHODS: Randomised controlled trials comparing the elective use of HFV with any form of CMV were identified. Trials were classified according to the ventilation strategies used for HFV and CMV and oscillator device employed. For cumulative meta-analyses, trials were arranged by the following covariables: mean duration until randomisation, Paco(2) limits, publication date, and sample size. Odds ratios (OR) and 95% confidence intervals were calculated using fixed and random effects models. RESULTS: Seventeen randomised trials enrolling 3776 patients were included. Unlike previous meta-analyses, there was no significant difference in the incidence of bronchopulmonary dysplasia or death (OR 0.87, 0.75-1.00) and severe intraventricular haemorrhage grade 3-4 (1.14, 0.96-1.37). The incidence of air leaks (OR 1.23, 1.06-1.44) was significantly increased with HFV. Subgroup analyses and cumulative meta-analyses demonstrated that trial results were related to the ventilation strategies used for HFV and CMV. No influence was found for mean time to randomisation, degree of permissive hypercapnia, or sample size. CONCLUSIONS: Heterogeneity among trials of elective HFV compared to CMV in preterm infants is mainly due to differences in ventilatory strategies. Optimising CMV strategy appeared to be as effective as using HFV in improving pulmonary outcome in preterm infants.

Effects of postnatal estradiol and progesterone replacement in extremely preterm infants.

The fetus is supplied from the placenta with estradiol (E2) and progesterone (P) in increasing amounts during gestation. After delivery of a premature infant, placental supply is disrupted, resulting in a rapid decrease in E2 and P. Replacement of these placental hormones may restore intrauterine conditions and may be beneficial for bone mineral accretion, clinical course, and outcome. Thirty female infants with a median gestational age of 26.6 weeks (between 24.1-28.7) and a birth weight of 675 g (370-990) were randomized to receive E2 and P replacement, aiming to maintain plasma levels equaling the intrauterine levels, or no replacement. The E2 and P replacement was started iv and was followed by transepidermal administration for a total duration of 6 weeks. Repeated measurements included plasma levels of E2, P, FSH, and LH; uterine volume; calcium and phosphorus in spot urine specimens; and bone mineral accretion by single photon absorption densitometry. Further, the incidence of chronic lung disease and various clinical outcome data were recorded. The plasma levels of E2 and P were within the intrauterine range with median replacements of 2.30 mg/kg x day E2 (1.13-6.23) and 21.20 mg/kg x day P (11.23-27.36), iv. Three- and 6-fold higher doses of E2 and P were needed via the transepidermal route. The uterine volumes increased, and FSH and LH as indicators for biological effectiveness were significantly lowered with replacement. The bone mineral accretion rates tended to be higher, and the incidence of chronic lung disease tended to be lower (0% vs. 29%; P = 0.097). E2 and P replacement via iv and transepidermal routes is capable of maintaining plasma levels as high as those in utero with biological effectiveness. Trends toward improved postnatal bone mineral accretion and less chronic lung disease were found with the hormone replacement. Further and more extensive studies are warranted to address the role of this new approach in the care of extremely premature infants.

Follow-up examination at the age of 15 months of extremely preterm infants after postnatal estradiol and progesterone replacement.

A randomized controlled pilot study was performed with a sample of extremely preterm infants to evaluate the impact of postnatal estradiol and progesterone replacement on postnatal bone mineral accretion. Twenty-five of 30 infants in the pilot study survived, and of these, 24 infants were available for the follow-up examination at a median chronological age of 18.1 months (minimum-maximum, 17.0--20.6) corresponding to a corrected age of 14.8 months (minimum-maximum, 12.9--17.4). Somatic growth data and bone mineralization showed no differences between the hormone-treated and control group infants. The deviation of the skeletal age from the corrected age was 0.0 months (minimum-maximum, -7.7 to 7.4) for hormone-treated infants compared with -1.7 months (minimum-maximum, -7.5 to 5.9) for the control group. The Bayley scales mental and psychomotor developmental indexes were 89 (minimum-maximum, 71--107) and 101 (minimum-maximum, 49--121) for the hormone-treated infants and 93 (minimum-maximum, 49--111) and 71 (minimum-maximum, 49--121) for the control group infants, respectively (mental developmental index, P = 1.0; psychomotor developmental index, P = 0.14). The normal psychomotor development in the hormone-treated infants compared with the below average development in the control group infants is encouraging and indicates the potentially important integrative role of sex steroids for the developing brain. Larger studies on the effects of the postnatal replacement of estradiol and progesterone in extremely preterm infants are warranted.

Delivery room management of extremely low birth weight infants: spontaneous breathing or intubation?

OBJECTIVE: To study the effect of two different delivery room (DR) policies on the rate of endotracheal intubation and mechanical ventilation (EI/MV) and short term morbidity in extremely low birth weight infants (ELBWI; <1000 g, >/=24 weeks). METHODS: Retrospective cohort study of 123 inborn ELBWIs born in 1994 and in 1996. DR policies have changed. Until 1994, ELBWIs were intubated immediately after delivery when presenting the slightest signs of respiratory distress or asphyxia after initial resuscitation using a face mask and a handbag. During 1995, the guidelines for respiratory support were changed. In 1996, continuous (15 to 20 seconds), pressure controlled (20 to 25 cm H2O) inflation of the lungs using a nasal pharyngeal tube, followed by continuous positive airway pressure (CPAP; 4 to 6 cm H2O) was applied to all ELBWIs immediately after delivery to establish a functional residual capacity and perhaps to avoid EI/MV. In addition to the changes in respiratory support, the prevention of conductive and evaporative heat loss was improved in 1996. For analysis of morbidity and mortality, infants were matched for gestational age and birth weight. RESULTS: The rate of EI/MV in the DR decreased from 84% in 1994 to 40% in 1996. In 1996, 25% of the ELBWIs were never intubated (7% in 1994), but 35% of the ELBWIs needed secondary EI/MV, primarily because of respiratory distress syndrome (RDS). Initial ventilator settings, ventilator days, mortality, and morbidity were not different between ELBWIs with EI/MV in the DR and infants with secondary EI/MV attributable to RDS in the intensive care unit. ELBWIs with no EI/MV that was caused by RDS had a lower morbidity (ie, bronchopulmonary dysplasia, intraventricular hemorrhage >grade 2 and/or periventricular leukomalacia), mortality, and fewer hospital days (mean: 79 vs 105 days). The incidence of gastrointestinal adverse effects like feeding intolerance or necrotizing enterocolitis was not increased in 1996. PaCO2 was significantly higher at admission to the neonatal unit in ELBWIs with CPAP in 1996 (54 +/- 15 mm Hg, 7.2 +/- 2.0 kPa) compared with infants with EI/MV in 1994 (38 +/- 11 mm Hg, 5.1 +/- 1. 5 kPa. A total of 26% of spontaneously breathing infants had hypercapnia (PaCO2 >/=60 mm Hg [8.0 kPa]), compared with 7% of infants with EI/MV in 1994. Within the first few hours of life, PaCO2 decreased to 46 (32 to 57) mm Hg (6.1 [4.3 to 7.6] kPa) in never intubated ELBWIs (n = 17), but increased to 70 (57 to 81) mm Hg (9.3 [7.6 to 10.8] kPa) in ELBWIs (n = 14) with RDS and secondary EI/MV (age 5.5 [1 to 44] hours). CONCLUSIONS: In our setting, the individualized intubation strategy in the DR restricted EI/MV to those ELBWIs who ultimately needed it, without increasing morbidity or mortality in infants with secondary EI/MV attributable to RDS. We speculate that an individualized intubation strategy of the ELBWI is superior to immediate intubation of all ELBWIs with slight signs of respiratory distress after birth.

Reduction of unnecessary antibiotic therapy in newborn infants using interleukin-8 and C-reactive protein as markers of bacterial infections.

OBJECTIVE: To examine whether the determination of interleukin 8 (IL-8) and C-reactive protein (CRP) in neonates with suspected nosocomial bacterial infection (NBI) is feasible and cost-effective in reducing antibiotic therapy. METHODS: Between April 1996 and May 1997, IL-8 was measured 260 times along with blood cultures, CRP, and immature-to-total-neutrophil (IT) ratio for suspected NBI in term and preterm neonates. All infants were retrospectively analyzed for NBI. Sensitivity, specificity, positive and negative predictive values, and 95% confidence intervals were calculated for IL-8, CRP, and IT ratio. Receiver-operating characteristic curves were analyzed to determine optimal thresholds. Between June 1997 and June 1998, IL-8 was measured 215 times in newborn infants with suspected NBI and the decision to start antibiotic therapy was based on increased IL-8 and/or CRP values. A cost-effectiveness analysis was performed and sensitivity, specificity, and receiver-operating characteristic curves were reevaluated. RESULTS: At the first suspicion of NBI, the combination of IL-8 >/= 53 pg/mL and/or CRP >10 mg/L detected culture-proven NBI with 96% sensitivity. The combined culture-proven and clinical NBI were detected with 93% sensitivity and 80% specificity. The use of IL-8 reduced unnecessary antibiotic therapy for suspected NBI by 73% and was cost-effective when compared with initiating antibiotic therapy based on clinical signs alone or based on clinical signs and an increased IT ratio and/or CRP. CONCLUSIONS: The combination of IL-8 and/or CRP is a reliable and early test for the diagnosis of NBI in newborn infants. Using the combination of IL-8 and/or CRP to restrict antibiotic therapy to truly infected infants reduces unnecessary antibiotic therapy and is cost-effective.

Interleukin-6: a sensitive parameter for the early diagnosis of neonatal bacterial infection.

OBJECTIVE: Early recognition is important for the successful treatment and outcome of neonatal infections. As interleukin-6 (Il-6) plays a critical role in the induction of C-reactive protein (CRP) synthesis in the liver, it was hypothesized that this cytokine could be detected earlier in blood than the CRP during the course of bacterial infection. DESIGN: In a prospective study of 298 newborns who were admitted to the nursery unit, CRP levels, blood cell count with differential, and Il-6 levels were determined at the time of admission and 24 hours after admission. Seventy-six newborns were excluded from the study because of incomplete or incorrect blood sampling. RESULTS: The remaining 222 newborns were assigned to one of five groups: 11 newborns with blood culture-positive sepsis (sensitivity of Il-6 on admission 73%), 15 newborns with clinical sepsis (sensitivity of Il-6 on admission 87%), 41 newborns with infection (sensitivity of Il-6 on admission 68%), and 54 newborns without clinical and laboratory evidence of infection (specificity 78%). The remaining 101 newborns were defined as a mixed group because the diagnosis of neonatal infection could not clearly be made. Seventy-five percent of infected newborns had negative Il-6 levels 24 hours after admission. Of the 18 infected newborns with negative Il-6 levels on admission, 10 newborns had elevated CRP levels, suggesting that Il-6 was already negative because of the short half-life of Il-6. Sensitivity of Il-6 in CRP-negative newborns on admission was 100% in newborns with blood culture-positive and clinical sepsis. Il-6 was more sensitive than CRP in infected newborns on admission (73% vs 58%). CONCLUSION: Il-6 is a sensitive parameter for diagnosing neonatal bacterial infection. The combination of CRP and Il-6 seems to be the ideal tool for the early diagnosis of neonatal infection.

X/autosome translocation in three generations ascertained through an infant with trisomy 16p due to failure of spreading of X-inactivation.

We report on a reciprocal translocation t(X;16)(q28;p12) detected in a newborn girl with clinical manifestations of partial trisomy 16p. A balanced translocation was found in the mother and in the maternal grandmother. Replication studies on lymphocytes and fibroblasts showed nonrandom X-inactivation in both the patient and her mother. In the mother, the derivative X (der(X)) was active, whereas the normal X was late replicating. In contrast, in the patient the der(X) was late replicating, and there was no spreading of X-inactivation onto the autosomal segment, thus giving an explanation for the full clinical picture of partial trisomy 16p.

Comparison of procalcitonin with interleukin 8, C-reactive protein and differential white blood cell count for the early diagnosis of bacterial infections in newborn infants.

OBJECTIVE: To evaluate procalcitonin (PCT) as a test for early diagnosis of bacterial infections (BI) in newborn infants and to compare the results of PCT with those of interleukin 8 (IL-8), C-reactive protein (CRP) and differential white blood cell count. STUDY DESIGN: PCT was prospectively measured along with IL-8, CRP and differential white blood cell counts and blood cultures in 197 newborn infants at the first suspicion of bacterial infection. PCT, IL-8, CRP and differential white blood cell counts were analyzed for sensitivity, specificity and positive and negative predictive values after receiver operating characteristic curve analysis for best thresholds. The kinetics of PCT was determined in infants with and without BI. RESULTS: Forty-six infants were diagnosed clinically as having BI, of whom 9 had BI with positive blood cultures. At a cutoff value of 0.50 microg/l, PCT detected combined culture-proved and clinical BI with a sensitivity of 57% (95% confidence interval, 41%, 71%) and a specificity of 66% (95% confidence interval, 57%, 74%). The combination of IL-8 > or =70 ng/l and/or CRP >10 mg/l achieved a sensitivity of 91% (95% confidence interval, 79%, 98%) and a specificity of 73% (95% confidence interval, 64%, 81%). PCT values of infected and not infected infants tended to rise for 24 h after initial evaluation and then decreased. CONCLUSION: The combination of IL-8 and CRP is more reliable than PCT as a test for early diagnosis of BI in newborn infants.

Effect of the TI/TE ratio on mean intratracheal pressure in high-frequency oscillatory ventilation.

In high-frequency oscillatory ventilation (HFOV), an adequate mean airway pressure is crucial for successful ventilation and optimal gas exchange, but air trapping cannot be detected by the usual measurement at the y piece. Intratracheal pressures produced by the high-frequency oscillators HFV-Infantstar (IS), Babylog 8000 (BL), and the SensorMedics 3100A (SM) [the latter with either 30% (SM30) or 50% (SM50) inspiratory time] were investigated in four anesthetized tracheotomized female piglets that were 1 day old and weighed 1.6-1.9 kg (mean 1.76 kg). The endotracheal tube was repeatedly clamped while the piglets were ventilated with an oscillation frequency of 10 Hz, and the airway pressure distal of the clamp was recorded as a measure of average intrapulmonary pressure during oscillation. Clamping resulted in a significant decrease of mean airway pressure when the piglets were ventilated with SM30 (-0.86 cmH2O), BL (-0.66 cmH2O), and IS (-0.71 cmH2O), but airway pressure increased by a mean of 0.76 cmH2O with SM50. Intratracheal pressure, when measured by a catheter pressure transducer at various oscillation frequencies, was lower than at the y piece by 0.4-0.9 cmH2O (SM30), 0.3-3 cmH2O (BL), and 1-4.7 cmH2O (IS) but was 0.4-0.7 cmH2O higher with SM50. We conclude that the inspiratory-to-expiratory time (TI/TE) ratio influences the intratracheal and intrapulmonary pressures in HFOV and may sustain a mean pressure gradient between the y piece and the trachea. A TI/TE ratio < 1:1 may be useful to avoid air trapping when HFOV is used.