[Kinetic therapy of severe meconium aspiration syndrome]. / Kinetische Therapie bei einem schweren Mekoniumaspirations-Syndrom.

Recent studies showed the possible positive effect of body position changes during mechanical ventilation of severe lung diseases in adult patients. In neonatology kinetic therapy is still rarely used, therefore we present this case report. A full term newborn suffering from severe MAS and peripartal asphyxia was transferred to our NICU to perform extracorporeal lung support, if necessary. After application of a natural porcine surfactant and start of inhalative nitric oxide therapy (10 ppm) a clinical stabilisation was possible. Because of hypercapnia, high frequency oscillation ventilation was introduced later on. The PaCO2 values decreased quickly. A few days later severe pulmonary secretion problems occurred, which led to atelectasis and barotrauma due to local hyperinflation. After several different ventilation strategies had failed to improve the situation, kinetic therapy in combination with conventional mechanical ventilation was started. Under this therapy-concept it was possible to reventilate the atelectatic lung areas, and quickly an improvement of oxygenation was seen. Weaning from the respirator was possible within one week. In conclusion, we think that an important progress in therapy was due to kinetic therapy.

Serial lumbar tapping to prevent posthaemorrhagic hydrocephalus after intracranial haemorrhage in preterm infants.

Posthaemorrhagic ventricular dilation following intraventricular haemorrhage is a serious problem with high morbidity in preterm babies. No consensus exists as to the treatment of intraventricular haemorrhage and as to the treatment or prophylaxis of posthaemorrhagic ventricular dilation. Serial lumbar tapping was already in use to treat existing or being in the offing ventricular dilation. In the present study we evaluated the incidence of posthaemorrhagic hydrocephalus when lumbar tapping was initiated early, i. e. immediately before ventricular dilation had started. Between January 1989 and December 1996 37 preterm infants suffering from intraventricular haemorrhage grade III or grade III plus periventricular haemorrhage were enrolled in this study. Lumbar tapping was started as soon as possible: median (25. percentile-75. percentile) two (0-4) days after onset of haemorrhage. A median of 11 (8-17) punctures was performed in each patient. The outcome was as follows: 6 patients (16.2%) showed complete remission, 24 (64.9%) developed ventriculomegaly and 7 (18.9%) developed posthaemorrhagic hydrocephalus with subsequent need of shunt implantation. With the low incidence of shunt implantations in our study we suggest to reconsider the effectiveness of SLP performed immediately after onset of haemorrhage.

Spontaneous gastrointestinal perforation in very-low-birth-weight infants--a rare complication in a neonatal intensive care unit.

Over a 6-year period (1989-1995), gastrointestinal (GI) perforation was diagnosed in nine preterm infants (mean gestational age 27 weeks, mean birth weight 872 g). Three presented with necrotizing enterocolitis (NEC), two with indwelling-tube-induced perforation of the stomach, one with small-left-colon syndrome, and another with meconium ileus. Spontaneous intestinal perforation occurred in two similar very-low-birth-weight (VLBW) infants, in the distal ileum, on days 8 and 9 of life, respectively. The only clinical sign was extensive abdominal distension, and abdominal X-ray studies revealed free peritoneal air. All findings were distinct from those associated with NEC. Their further clinical course was complicated by reperforation on day 32 and 39, respectively. They subsequently recovered and presented without GI problems at the corrected ages of 4 and 2 months, respectively. In contrast to high mortality of 57% in the group with non-spontaneous intestinal perforations, spontaneous perforation seems to have a good prognosis even in VLBW infants if diagnosed and treated promptly.

Continuous renal replacement therapy in critically ill patients.

We describe our experience with continuous renal replacement therapy (CRRT) in critically ill neonates. From June 1995 to June 1997 36 critically ill oliguric or anuric infants and children underwent continuous arterio-venous (N = 17) or veno-venous (N = 15) renal support. In addition, four neonates were treated with continuous ultrafiltration (CUF) during extracorporeal membrane oxygenation (ECMO) because of severe diuretic-resistant hypervolemia. Their mean age was 9.8 +/- 1.5 days, their mean body weight 3.0 +/- 0.1 kg. The membrane surface area of the hemofilters ranged from 0.015 m2 to 0.2 m2 and the priming volume from 3.7 to 15 ml. For pump-driven hemofiltration a roller pump with pressure alarms, an air trap, an air bubble detector, and small blood lines was used. Fluid balance was controlled by a microprocessor controlled unit. The ultrafiltrate substitution fluid was based on bicarbonate in the majority of the patients and was partially or totally replaced according to the clinical situation. The mean duration of renal support was 97 +/- 20 hours, ranging from 14 to 720 hours. During arterio-venous and veno-venous hemofiltration the mean blood flow rates were 7.0 +/- 1.2 ml/min and 23.1 +/- 2.4 ml/min (P < 0.01), respectively, and the mean ultrafiltration rates 3.3 +/- 0.4 and 9.5 +/- 1.9 ml/min/m2 (P < 0.01), respectively. During continuous hemodiafiltration urea clearances increased by 300%. Overall survival rate was 66%. CRRT related complications included local bleeding at the catheter entrance site, partial thrombosis of the inferior or superior caval veins and transient ischemia due to femoral artery catheters. Continuous hemofiltration either driven in the arterio-venous or veno-venous mode is a very effective method of renal support for critically ill neonates to control fluid balance and metabolic derangement. Urea clearance can be improved by adding some dialysate fluid in a countercurrent direction to blood flow.

Assessment of lung function in neonates during extracorporeal membrane oxygenation.

We report our experience with pulmonary function testing in 11 out of 22 full-term neonates with severe respiratory failure, treated at the ECMO center Graz (Austria) during the period from 1990 to 1995. Altogether 17 out of 22 patients survived ECMO and all of them were successfully weaned from ECMO. Pulmonary function was assessed by monitoring expiratory tidal volume on the ventilator and estimating respiratory system compliance from the ratio tidal volume/(PIP-PEEP). In addition, compliance, and functional residual capacity were measured using a computerized pulmonary function system (PEDS). Compliance (mean +/- SD) decreased markedly after 24 hours of ECMO, compared with baseline values (0.20 +/- 0.12 vs 0.12 +/- 0.13 ml/cmH2O/kg) and was significantly higher (0.43 +/- 0.14 ml/cmH2O/kg, p < 0.01) before ECMO stop. When tidal volumes increased continuously ECMO blood flow could be decreased, indicating lung recovery. Most patients had a tidal volume of > 7 ml/kg prior to decannulation. Functional residual capacity and corresponding dynamic compliance, measured in 5 patients, ranged from 18.6 to 29.6 ml/kg and 0.49 to 0.57 ml/cmH2O/kg at this time. Functional residual capacity (mean +/- SD) increased significantly when surfactant was administered to promote weaning from ECMO (8.28 +/- 0.9 vs 19.0 +/- 1.0 ml/kg, p < 0.01). We conclude that the assessment of lung function has improved our understanding of pulmonary recovery during ECMO. Its clinical significance in determining the optimum time of weaning from ECMO needs further evaluation.

Venous thrombosis in and after extracorporeal membrane oxygenation: detection and follow-up by color Doppler sonography.

The purpose of our study was to evaluate thrombosis of venous vessels during and after extracorporeal membrane oxygenation (ECMO) using color Doppler sonography. We prospectively performed serial color Doppler sonography investigations in 30 ECMO patients [age: newborn to 3 years, male:female = 20:10, venoarterial (VA) ECMO = 18, venovenous (VV) ECMO = 12]. During ECMO obstruction and/or thrombosis of the superior vena cava (SVC) was observed in 2 neonates on VA ECMO. Furthermore, a thrombotic clot from an initially open duct of Arantii with partial portal vein thrombosis, reaching into the inferior vena cava (IVC), occurred despite adequate heparinization. After ECMO, late septic SVC thrombus occurred in one neonate. IVC thrombus was observed in two pediatric VV ECMO patients. The overall incidence of venous clots was 20 % (6 of 30). Routine color Doppler sonography monitoring of vessels in children on and after ECMO was found to be useful for early detection of venous thrombosis. It enabled consequent administration of appropriate therapy as well as follow-up after decannulation and reconstruction.

Activation of the clotting system during extracorporeal membrane oxygenation in term newborn infants.

OBJECTIVES: To determine the degree of clotting activation that occurs with the usual anticoagulation regimen with systemic heparinization. METHODS: To allow a standardized comparison of the patients, this study focused on the first 48 hours of extracorporeal membrane oxygenation (ECMO) in term newborn infants. The ECMO perfusion circuit consisted of a roller pump, silicone membrane lungs, and silicone rubber tubing. Coagulation was controlled routinely by measuring prothrombin time, fibrinogen, antithrombin III, and reptilase time. Platelet counts, activated clotting time, and heparin concentration were controlled regularly. The following specific activation markers of the clotting system were measured: prothrombin activation fragment 1 + 2(F1+2), thrombin-antithrombin III complexes, and D-dimer. Measurements were done before the start of ECMO, after 5 minutes, and at hours 1, 2, 3, 4, 6, 12, 24 and 48. RESULTS: All seven term infants had excessively high levels of clotting activation markers within the first 2 hours of ECMO: F1+2, 11.6(+/- O.9) nmol/L (mean +/- SEM); thrombin-antithrombin, 920(+/- 2.2) microg/L; D-dimer, 15.522(+/- 3.689) ng/L. During the next 46 hours of ECMO, F1+2 and thrombin-antithrombin III complexes decreased from those high values, whereas D-dimer did not. The increase of activation markers was accompanied by low fibrinogen, low platelet counts. and prolongation of reptilase time. CONCLUSIONS: These findings fit the pattern of consumptive coagulopathy during neonatal ECMO, especially in the first 24 hours.

[Extracorporeal membrane oxygenation in newborn infants and children]. / Die extrakorporale Membranoxygenierung bei Neugeborenen und Kindern.

The purpose of this report is to describe our experience with veno-arterial (VA) and veno-venous extracorporeal membrane oxygenation (VV-ECMO) for neonates and children with severe acute respiratory or cardiocirculatory failure. From 1990 to 1994 20 neonates and 12 children were treated at the ECMO center in Graz. Indications for ECMO were acute respiratory failure in 27 patients and cardiocirculatory failure in 5 patients. Mean duration of ECMO was 228 +/- 30 hours. Fifteen neonates were weaned from ECMO and were subsequently extubated. Of the 12 children 7 had severe acute respiratory failure and underwent VV-ECMO. Five of these 7 children were weaned from ECMO and subsequently extubated. Only two of 5 patients with cardiac ECMO support could be weaned from bypass; one patient subsequently died, but the other patient is a long-term survivor. All patients with cardiac ECMO support after open heart surgery had severe mediastinal bleeding. The survival rate in neonates and pediatric patients with respiratory failure treated by ECMO was 75% and 71%, respectively, whereas it was only 20% in children with cardiocirculatory failure. Major complications on ECMO were local and intracerebral bleeding. ECMO is an effective therapy for neonates and children with acute respiratory failure. It is less effective for cardiac support in children after open heart surgery, but the use of heparin-layered ECMO systems might increase the safety of the procedure.

Sonographically guided cannula positioning for extracorporeal membrane oxygenation.

Drainage problems due to catheter malpositioning are acutely life-threatening in patients undergoing extracorporeal membrane oxygenation. In order to reduce these complications we introduced sonographically guided catheter positioning. We compare the outcome in a group of patients with blind cannula positioning to that in a group with sonographically guided catheter positioning. Our results show that neonates and young infants especially are at high risk of drainage problems due to catheter malposition and that their outcome could be markedly improved by introducing sonographically guided cannula insertion.

[Successful treatment of therapy refractory shock lung in a newborn infant with congenital varicella using extracorporeal membrane oxygenation]. / Erfolgreiche Behandlung einer therapierefraktären Schocklunge bei einem Neugeborenen mit connatalen Varicellen mittels Extracorporaler Membranoxygenierung.

A newborn with congenital varicella complicated by varicella pneumonia was transferred to our hospital on day 16 of life for the consideration of extracorporeal membrane oxygenation (ECMO). The newborn received varicella zoster immunoglobulin 13 hours after birth since the mother developed a varicella exanthema two days before delivery. On day 10 of life the newborn became clinically symptomatic with red macules and pustules. The chest roentgenogram revealed reticular pulmonary infiltrates in the right upper lobe. Antibacterial chemotherapy was initiated. In the following days the cutaneous lesions progressed, and respiratory symptoms like tachypnoea and oxygen dependence occurred. Chest roentgenograms revealed diffuse reticular and patchy pulmonary infiltrates. On day 14 of life antiviral chemotherapy with acyclovir was started. ECMO was initiated in the veno-arterial mode on day 17 due to severe respiratory failure despite maximal conventional assisted ventilation and carried out for 14 days. With the age of 10 weeks he was discharged from the hospital with mild chronic lung disease without oxygen requirements and without neurological handicap. ECMO might be considered as life saving support in newborns with severe congenital varicella, considered to have a high mortality risk.

[Diagnosis of lung function in intensive care of newborn infants]. / Lungenfunktionsdiagnostik bei intensivgepflegten Neugeborenen.

We report our initial experience with pulmonary function testing in neonates during intensive care, using an automated, computerized system (PEDS), which allows non-invasive and rapid determination of pulmonary mechanics and energetics such as compliance, resistance and respiratory drive, and measurement of lung volume (functional residual capacity). This method is used for better physiological characterization and quantification of the respiratory status, to assess the effectiveness of mechanical ventilation and pharmacological therapy, and to guide weaning and extubation. Despite certain limitations with regard to direct evaluation of the respiratory status especially in very sick neonates, pulmonary function testing has contributed to a better understanding of the pathophysiological mechanisms of pulmonary dysfunction and can also be useful to optimize clinical management of neonates in intensive care.

[Artificial respiration of premature infants]. / Künstliche Beatmung beim Frühgeborenen.

Better understanding of respiratory physiology and progress in ventilator technology have contributed to improved mortality and morbidity of premature neonates. Yet, pulmonary complications remain high and there is no consensus about the optimal regimen of mechanical ventilation. We report our satisfactory 10-year experience with conventional mechanical ventilation based on a relatively low incidence of pulmonary barotrauma. The introduction of surfactant has facilitated the ventilatory management of premature neonates since the usually rapid improvement of the acute lung disease after surfactant administration allows for earlier weaning from mechanical ventilation. However, our own results and the results from most surfactant studies show no significant reduction in the incidence of intraventricular haemorrhage. Thus, though mechanical ventilation and surfactant administration are milestones in neonatal therapeutic management, the problems encountered in very low birth weight neonates both with respect to mortality and morbidity have not been generally solved and underline the role of optimal perinatal management.