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J C Möller

Publications and source records attributed to J C Möller.

51 records · Page 3Linked to original sources
PubMed1992

Effect of extracorporeal membrane oxygenation on tobramycin pharmacokinetics in sheep.

BACKGROUND AND METHODS: Critically ill infants undergoing extracorporeal membrane oxygenation (ECMO) therapy often receive multiple pharmacologic agents. Although the disposition of many drugs has been assessed in patients undergoing cardiopulmonary bypass and in patients receiving mechanical ventilation, only limited data exist for selected medications in patients undergoing ECMO. To evaluate the potential influence of ECMO on aminoglycoside pharmacokinetics, we studied the disposition of tobramycin in ten sheep before and during ECMO therapy. Each sheep received a single iv dose of tobramycin during a control period before ECMO and on a study day during ECMO. Identically timed serial blood samples over 4 hrs were obtained after each tobramycin dose. Paired serum tobramycin concentrations were obtained pre- and postmembrane oxygenator during ECMO in six sheep. RESULTS: Alterations in specific pharmacokinetic variables for tobramycin were observed as a result of ECMO. Estimates of elimination half-life and volume of distribution for tobramycin were significantly increased during ECMO as compared with control (pre-ECMO) values (1.8 +/- 0.3 vs. 2.7 +/- 0.8 [SD] hrs [p < .01] and 0.3 +/- 0.1 vs. 0.5 +/- 0.2 L/kg [p < .005], respectively). Tobramycin body clearance was unaffected by the procedure (1.8 +/- 0.8 vs. 1.7 +/- 0.4 mL/min/kg). Paired serum tobramycin concentrations obtained pre- and postmembrane oxygenator demonstrated no drug removal. CONCLUSIONS: These data suggest that ECMO circuitry does not sequester tobramycin and that the prolonged elimination half-life observed during ECMO therapy is not due to a change in drug clearance but is due to an ECMO-induced increase in tobramycin volume of distribution. To achieve and maintain preselected target tobramycin serum concentrations during ECMO, the usual dosage interval should remain unchanged, but the dose should be increased to compensate for the alteration in the drug's volume of distribution. The clinical applicability of these findings needs to be confirmed in carefully controlled clinical studies involving infants receiving ECMO therapy.

Animals↗
PubMed1992

Prophylactic low-dose vancomycin treatment in very-low-birth-weight infants.

For the prophylaxis of septicemia with coagulase-negative staphylococci in a high-risk very-low-birth-weight population, we administered 5 mg/kg of vancomycin every 12 h. Distribution volume and half-life of vancomycin were determined. Serum peak and trough levels were obtained on day 3 of treatment. With this low-dose regimen, serum concentrations in the therapeutic range were achieved in 35 of the 45 patients. Distribution volume and half-life were 0.692 liters/kg and 7.4 h, respectively. The distribution volume was not related to the gestational age; the half-life in the group of patients with a gestational age < 30 weeks was considerably higher. The 10 small-for-gestational-age children had a significantly smaller distribution volume. The vancomycin trough levels correlated with the serum creatinine concentrations and, therefore, with the gestational age. Our study indicates that this low vancomycin dose is sufficient in very-low-birth-weight infants to achieve therapeutic serum levels, being suitable for both prophylaxis and sepsis therapy.

Creatinine↗
PubMed1992

[Poisoning with volatile hydrocarbons. 3 cases and a review].

BACKGROUND: Volatile crude oil derivates (hydrocarbons) are becoming more and more widely used in homes and during leisure activities. This leads to a high rate of intoxications with these products in children (5% of all pediatric intoxications, 25% of all lethal intoxications). Clinical courses, pathophysiology, and therapy of these intoxications are referred and studied. METHODS: Based on a literature review and 3 cases reports with different clinical courses, intoxications with volatile hydrocarbons are analyzed. RESULTS: The inhalation of volatile hydrocarbons causes an ARDS. This explains the high mortality. Early oxygen-treatment with PEEP-ventilation, however, facilitates a favourable outcome without residual defects as we demonstrate in one case. Another patient needs prolonged ventilatory support after a delayed start of therapy. A third patient cannot be saved even with ECMO. CONCLUSIONS: Initial pulmonary symptoms after hydrocarbon intoxication, such as coughing and cyanosis, are signs for a severe course. Immediate hospitalization with repetitive chest x-rays and adequate instant therapy are the only option to reduce the high mortality of this intoxication.

Child↗
PubMed1991

[The treatment of severe pulmonary hypertension in newborn infants using extracorporeal membrane oxygenation or conventional measures. An interinstitutional comparison].

In a two years retrospective study we analyzed neonates from a US and a German neonatal center with pulmonary hypertension (persistent fetal circulation--PFC). The US patients were treated with Extracorporeal Membrane Oxygenation (ECMO) the german patients with conventional methods as hyperventilation, catecholamines, and vasodilators. Both groups fulfilled the classical ECMO entrance criteria: an alveolar-arterial oxygen difference greater than 610 mmHg and an oxygenation index (i.e. mean airway pressure x FiO2 x 100/paO2 of greater than 40 mmHg. We compared anamnestic and respiratory parameters with the t-test for independent groups or the chi-square test accordingly. With one patient in each group the mortality was not significantly different and the rate of meconium aspirations was the same. The APGAR score at 5 min was significantly lower in the US group, prenatal care was undertaken in significantly less US than german patients. Time intervals between delivery and important therapeutic interventions as intubation, hyperventilation, first catecholamines were not significantly different between both groups. Also worst paO2, pH, and paCO2 were not significantly different. Mechanical ventilation was more aggressive in the US group, i.e. higher intermittent-mandatory-ventilation-rate and peak inspiratory pressure. On the one hand our studies demonstrate that even patients fulfilling ECMO criteria still have a good chance with conventional treatment. On the other hand differences in APGAR scores and prenatal care might indicate that hypoxic-ischemic influences alter the US-group morbidity.

Apgar Score↗
PubMed1989

[The left ventricular functional parameter in M-mode echocardiography in various administration rates of a loading dose of theophylline in premature infants].

The aim of study was to show a positive effect of theophylline on the cardiac pump function immediately after i.v. bolus injection of the loading dose. Therefore we recorded m-mode echocardiograms before and immediately after bolus injection (over 2-3 min) of 6 mg/kg theophylline. On studying 12 preterm infants we observed a reduction of the left ventricular shortening fraction and circumferential shortening velocity. In the second part of the study we administered the same dose of theophylline over a period of 20 min. No significant differences in m-mode echocardiographic parameters before and after infusion were seen. We attribute these results to incalculable effects of theophylline preload, wall distension, and afterload. Nonetheless slow application of theophylline loading dose is recommended in preterm infants.

Cardiac Output↗
PubMedDate not supplied

[Preventive antibiotic administration for prevention of nosocomial septicemia in very small premature infants (VLBW infants)--preventive vancomycin administration against infections with coagulase negative streptococci--prevention of translocation with oral cefixime therapy in intestinal colonization with pathogenic gram-negative pathogens].

VLBW-infants below 1500 g of birth weight have a quite high risk to acquire a nosocomial sepsis. 20-40% of all infants exhibit signs of nosocomial infection once during neonatal intensive care. The rate of infection is related to technique and amount of used invasive devices as to gestational age. Coagulase-negative staphylococci (CONS) and gram-negative organisms contribute most to these cases of sepsis. In a three phase study we tried to demonstrate the efficacy of different mechanisms to change the rate of nosocomial sepsis. During the first phase a strict hygienical protocol was enforced as isolation, care with sterile gloves and aseptic techniques in introducing and maintaining i.v. lines. In a second phase we started a randomized controlled study of prophylactic vancomycin (10 mg/kg/day in two doses). In a third phase we added an oral antibiotic regime with cefixime for all patients with positive cultures for gramnegative organisms under the hypothesis of translocation from the gut as the way of infection. During the first phase 23.7% of 76 patients enrolled acquired CONS-sepsis, 0.52% gramnegative sepsis. During the second phase (41 patients) 6 patients in the control group acquired CONS-sepsis, none in the vancomycin-group. The rate of gramnegative infections was not different (4 and 3 cases). During the third phase (vancomycin plus cefixime eventually in cases of positive stool cultures) no case of nosocomial sepsis occurred (35 patients, 11 positive cultures). The management used in phase 3 reduced the rate of nosocomial infections in VLBW-infants drastically.

Anti-Infective Agents↗
PubMedDate not supplied

[Pathogenetic concepts of neonatal necrotizing enterocolitis].

The pathogenesis of neonatal necrotizing enterocolitis is still unknown today. Only prematurity has been confirmed as a primary risk factor. Previous studies demonstrated the special pathophysiological conditions in prematurity. Differences in intestinal permeability, blood flow in anemia and hypoxemia, the uptake, transport, delivery and consumption of oxygen, the digestion of carbohydrates and proteins and in intestinal motility between premature and term infants exist. The diving-reflex too is important for intestinal pathophysiology in these patients. The central key of the pathogenesis is the evident vascular damage. Infectious agents, inflammatory mediators, circulatory insufficiency, feeding excess is followed by the initial mucosal damage. This results in an increased intestinal permeability also for inflammatory mediators, endotoxins, bacteria and gas. Ileus, stasis and gas production cause endotoxinemia and abdominal distension. Increased intraluminal pressure with or without activation of inflammatory mediators leads to an important vascular dysregulation. Consecutively these multiple facts cause the "ischemic looking" hemorrhagic necrosis, we call necrotizing enterocolitis.

Acute-Phase Proteins↗
PubMedDate not supplied

[Transitory prolongation of QT time in severely ill premature and newborn infants].

Over 24 months in a Neonatal Intensive Care Unit 118 electrocardiograms were recorded in the first three days of life. 12 preterm and term newborns had a corrected QT-time-prolongation over 0.44 s. Measurement of the ionized calcium level in these children revealed hypocalcemia in only four as a reason for QT-time-prolongation. One child had hypokalemia, one child suffered from accidental Bupivacain injection. In the other six children no known reasons for QT-time-prolongation could be found. The QT-time-prolongation persisted for a maximum of three months, no inherited QT-syndrome existed. We discuss a correlation of these transitory QT-time-prolongation with asphyxia which preexisted in all six children. Influences on catecholamine receptors of myocardium or changes in central sympathicotonus may be assumed.

Arrhythmias, Cardiac↗
PubMedDate not supplied

[A comparative study about the therapeutic effect of theophylline and doxapram in apnoeic disorders].

The objective of this study was to prove the superiority of doxapram compared to theophylline therapy in apneas of prematurity in very low birth weight infants. Therefore all VLBW infants (gestational age < 35 weeks) were randomized if they had in a 2 hours-interval more than 2 apneas, 4 bradycardias or 4 oxygen desaturations. They received either theophylline (loading dose 5 mg/kg b. w., 3 mg/kg b. w. bid) or doxapram by continuous infusion of 0.5 mg/kg/h. Apneas, bradycardias and desaturations were recorded from the trend analysis of our monitoring system over the first 3-days and a 7 days period and compared statistically (Mann-Whitney U-test). Plasma levels of both drugs and a polysomnographic recording were obtained during steady state conditions in parallel to a behavioral observation according to Prechtl. The recorded events were again compared using the Mann-Whitney U-test. Twenty patients were treated with theophylline, 14 with doxapram. In 9 patients of each group we could perform a polysomnography and behavioral observation. The incidence of apneas, bradycardias and desaturations in a 7 days-interval was not significantly different between both groups. Analyzing the first 3 days of treatment, however, we could detect a significantly lower rate of apneas in the doxapram group (2.5 apneas compared to 7 in the theophylline group, p < 0.037). In the polysomnographic recording and in our behavioral observations we could not record any significant differences between both groups. Therefore we can conclude that theophylline and doxapram are comparable in the treatment of apneas of prematurity, however, doxapram is superior to theophylline in reducing the rate of apneas in the first 3 days of treatment.

Apgar Score↗
PubMedDate not supplied

Pramipexole, a nonergot dopamine agonist, is effective against rest tremor in intermediate to advanced Parkinson's disease.

We evaluated the efficacy of the nonergot dopamine receptor agonist pramipexole in 16 patients with advanced Parkinson's disease and marked rest tremor during an "on" period. The patients were drawn from a larger placebo-controlled, double-blind, randomized trial, which was not originally designed to investigate the effect of pramipexole on tremor. Eleven patients received pramipexole. The first effects were seen with a pramipexole dose of 0.75 mg/d with a reduction of the tremor item A of Unified Parkinson's Disease Rating Scale (UPDRS III, "on" state) by 25% and of rigidity and akinesia by 22%. Under the highest dose, 4.5 mg/d, the tremor score was improved by 61% over baseline (p < 0.0056, Wilcoxon signed rank) and the sum of rigidity and akinesia items by 66% (p < 0.0038, Wilcoxon signed rank). Five patients received placebo and did not improve. Based on this sample of patients, the nonergot dopamine receptor agonist pramipexole appears to have a potent anti-rest tremor action while being effective against akinesia and rigidity.

Aged↗