Ulrich Merz

Are recurrent hyperglycemic episodes and median blood glucose level a prognostic factor for increased morbidity and mortality in premature infants </=1500 g?

Abstract Background: Tight blood glucose control with intravenous insulin reduces morbidity and mortality in adult surgical intensive care patients. This has never been investigated in premature infants weighing ≤1500 g. We investigate the relationship between blood glucose levels repeatedly elevated >150 mg/dL and median blood glucose levels in the first week of life on one hand, and morbidity and mortality in premature infants weighing ≤1500 g on the other. Patients and methods: The following data were collected from 252 premature infants weighing ≤1500 g at birth: demographic data, blood glucose levels at three set times during the day (capillary and arterial) in the first week of life, actual and relative elevation of blood glucose level ≥150 mg/dL, median blood glucose level, allocation of patients into groups according to number of elevated blood glucose levels ≥150 mg/dL (0, 1–3 or ≥4 incidents), and median blood sugar level in relation to mortality and morbidity like IVH, ROP, and sepsis. Results: A significant increase in mortality (P<0.0001) with increasing median blood glucose level and repeated (≥4) incidents of blood glucose levels ≥150 mg/dL and in infants with low gestational age (<27 weeks) were observed. There was no correlation between blood glucose level and morbidity. Conclusion: Premature infants with low gestational age (<27 weeks), elevated median blood glucose levels and/or repeatedly elevated blood glucose levels ≥150 mg/dL have a significantly increased mortality. However, further prospective studies considering the gestational age should determine the relationship between tight glucose control and mortality.

Partial Liquid Ventilation Reduces Release of Leukotriene B4 and Interleukin-6 in Bronchoalveolar Lavage in Surfactant-Depleted Newborn Pigs

Perfluorocarbons have been shown to reduce the inflammatory process generated by alveolar macrophages in vitro. The aim of this study was to evaluate the impact of different ventilator modalities such as partial liquid ventilation (PLV), conventional ventilation (CV), and high-frequency oscillatory ventilation (HFOV) on the release of inflammatory mediators in vivo. Acute lung injury was induced in 30 male piglets by repeated saline lavage (arterial oxygen tension, <60 mm Hg; fraction of inspired oxygen, 1.0). Thereafter, animals were randomly assigned to one of five groups of six animals each:1) 24 h of CV;2) 24 h of CV plus surfactant therapy (S+CV);3) 24 h of HFOV plus surfactant therapy (S+HFOV);4) 1 h of PLV followed by 23 h of CV (PLV); and 5) 24 h of CV without previous lung injury (control group). Piglets randomized to S+CV or S+HFOV received natural surfactant (100 mg/kg). PLV with FC-77 was started in an initial dose of 30 mL/kg over 30 min followed by 0.5 mL·kg−1·min−1 for another 30 min. After 1 h of PLV the animals were conventionally ventilated for 23 h. Before acute lung injury and after 24 h the number of inflammatory cells and the levels of IL-6, leukotriene B4, and tumor necrosis factor-α were measured in the bronchoalveolar lavage fluid. Additionally, the oxygenation index and the histopathologic damage were evaluated. Before acute lung injury, the number of inflammatory cells and the levels of mediators in bronchoalveolar lavage fluid were not different among the groups. After 24 h, the number of granulocytes in the PLV group was as low as in the control group. leukotriene B4 and IL-6 levels were found to be elevated in all groups except the control group (p < 0.01). The release of leukotriene B4 and IL-6 was lowest in the PLV group when compared with S+HFOV, S+CV, or CV (p < 0.05). No differences among the groups were detected for tumor necrosis factor-α. Although the concentrations of leukotriene B4 and IL-6 after PLV were lowest in the PLV group, histopathologic evidence of damage and the oxygenation index in the PLV group did not differ from that found in the S+CV or S+HFOV groups. In conclusion, PLV with perfluorocarbons may protect the lung from acute pulmonary inflammation more effectively than CV or HFOV does.

The clinical outcome after inferior vena cava thrombosis in early infancy

Abstract The clinical outcome after inferior vena cava thrombosis in early infancy is unknown. We report the clinical long-term follow-up of 12 patients presenting inferior vena cava thrombosis within their first months of life (gestational age: 24–41 weeks; follow-up: 7±3 years). Accompanying renal venous thrombosis occurred in 9, and adrenal bleeding in 4 patients. A central venous catheter was related to the thrombosis in only four patients. Heterozygous factor V Leiden mutation was found in two of the eight infants without central venous catheter. Thrombolysis was performed in seven and effective in three infants; one infant required surgical thrombectomy. In three of eight infants with ineffective or with no therapy, spontaneous recanalization occurred during follow-up. No patient died of the thrombosis. Although no long-term anticoagulatory prophylaxis was performed, none of the children with persisting occlusion (n=5) or stenosis (n=1) of the inferior vena cava developed symptomatic thrombo-embolic complications. However, extensive internal collaterals (n=6), visible varicosis (n=5), pain in the legs (n=3) and persisting renal disease (n=3) with arterial hypertension (n=2) were observed during follow-up. Conclusion Inferior vena cava thrombosis of early infancy frequently persists and may cause considerable long-term morbidity. New strategies for early and long-term therapy are necessary.

Three new cases of congenital agenesis of the trachea

Congenital absence of the trachea is a rare anomaly that might confront the obstetrician or neonatologist with an unexpected emergency. These patients present with cyanosis, severe respiratory distress, insufficient gas exchange, absence of audible crying and difficult or impossible endotracheal intubation. In more than 90% it is associated with further congenital malformations. Adequate oxygenation depends on the existence of a tracheo- or bronchooesphageal fistula and the length of the proximal trachea. We present the cases of three neonates with tracheal agenesis with tracheooesophageal fistula. Two of the neonates died within the first hour of life because endotracheal intubation was impossible and oxygenation through an oesophageally placed tube was insufficient. The third infant could be oxygenated through a tracheooesophageal fistula. The ventilation was at least insufficient and no surgical intervention was made. The diagnosis of a congenital absence of the trachea usually is made after birth because of the clinical signs and the course within the first minutes of life. The only way that the diagnosis can be made prenatally is by magnetic resonance imaging (MRI). The knowledge of this clinical picture helps to make decisions in an unexpected emergency in the immediate postpartum period and also in patients whose ventilation is very difficult right from the start.

Effects of single and multiple doses of perfluorocarbon in comparison with continuous partial liquid ventilation on gas exchange and lung pathology in newborn surfactant-depleted pigs

ObjectiveTo compare the efficacy of single, multiple, and continuous application of perfluorocarbon (PFC) FC-77 on gas exchange and lung pathology in a prolonged 24-hr study. DesignControlled animal trial. SettingResearch laboratory in a university setting. SubjectsTwenty-one newborn piglets (mean weight 1.94 kg). InterventionsAfter intubation and instrumentation, the anesthetized animals were randomized in three groups: a) animals receiving one 1-hr session of partial liquid ventilation (PLV) followed by 23 hrs of conventional ventilation (CV), designated as the single PLV (S-PLV) group; b) animals receiving multiple 1-hr sessions of PLV with intermittent CV, designated as the multiple PLV (M-PLV) group; and c) animals receiving continuous PLV over 24 hrs, designated as the continuous PLV (C-PLV) group. After lung injury was induced with repeated saline lavage, specific ventilatory treatment was initiated. The oxygenation index, Pao2/Fio2 ratio, and ventilatory efficacy index were determined before and after lung injury and during the 24-hr course. After 24 hrs, the lungs were removed for histopathologic examination. Measurements and Main Results Gas exchange variables improved within 60 mins in all groups after the initiation of the specific ventilatory treatment (p < .01). The best outcome was observed in the C-PLV group, which provided a continuously stable gas exchange over the 24-hr period. S-PLV initially improved gas exchange, but after 6 hrs all variables were impaired when compared with C-PLV (p < .01). M-PLV transiently improved gas exchange variables after each PFC application; however, M-PLV was associated with a significant deterioration of all pulmonary variables during the 24-hr course. The lungs of the animals in the M-PLV group demonstrated an increased lung injury score (p < .01) and increased morphometric values (p < .05) when compared with C-PLV. ConclusionsIn surfactant deficient lungs, single and multiple applications of PFC only transiently improved oxygenation. Multiple PFC fillings with intermittent gas ventilation led to a deterioration of gas exchange during the 24-hr study and severe lung damage. Continuous PLV provides the best gas exchange and the most favorable histopathologic outcome.

Successful Thrombolysis of Inferior Vena Cava Thrombosis in a Preterm Neonate

I nferior vena cava thrombosis accounts for an important percentage of neonatal venous thrombosesl-3 and is associated with various risk factors, such as use of central venous catheters, hereditary thrombophilia, low cardiac output, cardiac catheterization, asphyxia, infection, and hemolysis, elevated liver enzymes, and low platelet count (HELLP) syndrome. Although there may be a high risk for persisting venous occlusion and obstruction,3 guidelines for thrombolysis of neonatal inferior vena

Functional upper airway obstruction in a child with Freeman-Sheldon syndrome

Freeman-Sheldon syndrome is defined as a combination of microstomia, deep set eyes, small palpebral fissures, arthrogryposis with ulnar deviation of the hand, talipes equinovarus and generalized muscular hypertension. Respiratory and swallowing problems are frequently encountered in these patients due to small orifices of mouth and nose. Obstruction of the upper airway tract resulting in tracheostomy has only been described twice. The described child manifested the typical dysmorphic features of Freeman-Sheldon syndrome and suffered from serious respiratory distress and swallowing difficulties from birth. The boy died at the age of 7 months after accidental decannulation of the tracheostoma during sleep. He did not show anatomical or histopathological abnormalities in the pharyngeal, laryngeal or tracheal regions. We assume that the only explanation of the repeated obstructive episodes is a functional muscular obstruction.

Repeated doses of Perfluorocarbon in saline-lavaged piglets: Effects on gas exchange and lung pathology

Repeated doses of Perfluorocarbon in saline-lavaged piglets: Effects on gas exchange and lung pathology

Combination of surfactant and partial liquid ventilation (PLV) in newborn surfactant depleted piglets

Combination of surfactant and partial liquid ventilation (PLV) in newborn surfactant depleted piglets