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Matthias David

Publications and source records attributed to Matthias David.

13 recordsLinked to original sources
PubMed2006

Perinatal outcome in Berlin (Germany) among immigrants from Turkey.

PURPOSE: Are there differences regarding important perinatal outcome-parameters in Berlin relating to ethnicity? PATIENTS AND METHODS: A database was available covering 152,193 single deliveries in all hospitals in Berlin/Germany in the period 1993-1999, including 132,555 German women and 19,638 women of other ethnicities. Comparisons were made between a total of four pairs of sub-groups matched in terms of parity and social status (significance level P < 0.01). RESULTS: Pregnant migrants come for their first antenatal check-up significantly later, thus delaying the initiation of necessary diagnostic or therapeutic measures. Migrants show higher rates of prepartal and also postpartal anemia than the German women. In all sub-groups the German women had a significantly higher frequency of planned cesarean sections. Migrants were significantly less likely to receive an epidural anesthesia during delivery. It is also noticeable that the rate of congenital malformations of neonates is significantly higher in the migrant collectives. CONCLUSIONS: Important perinatal quality parameters such as infant and maternal mortality and rates of premature delivery have largely converged between German and Turkish migrant mothers. The differences found (e.g., rates of planned cesarean section, epidural anesthesia, or anemia) could be interpreted as indications of persistent differences in quality of care for migrants.

Congenital Abnormalities↗
PubMed2006

Emergency outpatient services in the city of Berlin: Factors for appropriate use and predictors for hospital admission.

OBJECTIVES: To determine the proportion of patients making inappropriate use of medical care at hospital emergency rooms. To identify the factors that influence appropriateness of use and the probability of subsequent hospital admission. METHODS: Data were collected from 815 patients at three gynaecological/internal medicine emergency clinics in Berlin, Germany using multiple data sources: (i) standardized interviews covered service use history, psychosocial variables, migration history and sociodemographics; (ii) medical data were retrieved from patients' medical records, including case histories, diagnoses and therapies; (iii) emergency room physicians were asked to evaluate patients' language comprehension, physician-patient relationship and treatment urgency. Statistical analyses included chi tests, correlational and logistic regression analyses. RESULTS: According to a self-constructed index measuring appropriateness of emergency service use, about half of the patients' visits would have to be classified as inappropriate. Age, chronic illness and the time of day of the emergency service attendance were significantly associated with appropriateness of use. The probability of a hospital admission following the emergency treatment increased with patients' age and the physician's evaluation of treatment urgency. Remarkably, and contrary to the results of international studies, the patient's ethnicity played no significant role with respect to the appropriateness of use of emergency outpatient services or the likelihood of subsequent hospital admission.

Adolescent↗
PubMed2006

Effect of a lung recruitment maneuver by high-frequency oscillatory ventilation in experimental acute lung injury on organ blood flow in pigs.

INTRODUCTION: The objective was to study the effects of a lung recruitment procedure by stepwise increases of mean airway pressure upon organ blood flow and hemodynamics during high-frequency oscillatory ventilation (HFOV) versus pressure-controlled ventilation (PCV) in experimental lung injury. METHODS: Lung damage was induced by repeated lung lavages in seven anesthetized pigs (23-26 kg). In randomized order, HFOV and PCV were performed with a fixed sequence of mean airway pressure increases (20, 25, and 30 mbar every 30 minutes). The transpulmonary pressure, systemic hemodynamics, intracranial pressure, cerebral perfusion pressure, organ blood flow (fluorescent microspheres), arterial and mixed venous blood gases, and calculated pulmonary shunt were determined at each mean airway pressure setting. RESULTS: The transpulmonary pressure increased during lung recruitment (HFOV, from 15 +/- 3 mbar to 22 +/- 2 mbar, P < 0.05; PCV, from 15 +/- 3 mbar to 23 +/- 2 mbar, P < 0.05), and high airway pressures resulted in elevated left ventricular end-diastolic pressure (HFOV, from 3 +/- 1 mmHg to 6 +/- 3 mmHg, P < 0.05; PCV, from 2 +/- 1 mmHg to 7 +/- 3 mmHg, P < 0.05), pulmonary artery occlusion pressure (HFOV, from 12 +/- 2 mmHg to 16 +/- 2 mmHg, P < 0.05; PCV, from 13 +/- 2 mmHg to 15 +/- 2 mmHg, P < 0.05), and intracranial pressure (HFOV, from 14 +/- 2 mmHg to 16 +/- 2 mmHg, P < 0.05; PCV, from 15 +/- 3 mmHg to 17 +/- 2 mmHg, P < 0.05). Simultaneously, the mean arterial pressure (HFOV, from 89 +/- 7 mmHg to 79 +/- 9 mmHg, P < 0.05; PCV, from 91 +/- 8 mmHg to 81 +/- 8 mmHg, P < 0.05), cardiac output (HFOV, from 3.9 +/- 0.4 l/minute to 3.5 +/- 0.3 l/minute, P < 0.05; PCV, from 3.8 +/- 0.6 l/minute to 3.4 +/- 0.3 l/minute, P < 0.05), and stroke volume (HFOV, from 32 +/- 7 ml to 28 +/- 5 ml, P < 0.05; PCV, from 31 +/- 2 ml to 26 +/- 4 ml, P < 0.05) decreased. Blood flows to the heart, brain, kidneys and jejunum were maintained. Oxygenation improved and the pulmonary shunt fraction decreased below 10% (HFOV, P < 0.05; PCV, P < 0.05). We detected no differences between HFOV and PCV at comparable transpulmonary pressures. CONCLUSION: A typical recruitment procedure at the initiation of HFOV improved oxygenation but also decreased systemic hemodynamics at high transpulmonary pressures when no changes of vasoactive drugs and fluid management were performed. Blood flow to the organs was not affected during lung recruitment. These effects were independent of the ventilator mode applied.

Acute Disease↗
PubMed2006

Alternative protocol to initiate high-frequency oscillatory ventilation: an experimental study.

INTRODUCTION: The objective was to study the effects of a novel lung volume optimization procedure (LVOP) using high-frequency oscillatory ventilation (HFOV) upon gas exchange, the transpulmonary pressure (TPP), and hemodynamics in a porcine model of surfactant depletion. METHODS: With institutional review board approval, the hemodynamics, blood gas analysis, TPP, and pulmonary shunt fraction were obtained in six anesthetized pigs before and after saline lung lavage. Measurements were acquired during pressure-controlled ventilation (PCV) prior to and after lung damage, and during a LVOP with HFOV. The LVOP comprised a recruitment maneuver with a continuous distending pressure (CDP) of 45 mbar for 2.5 minutes, and a stepwise decrease of the CDP (5 mbar every 5 minute) from 45 to 20 mbar. The TPP level was identified during the decrease in CDP, which assured a change of the PaO2/FIO2 ratio < 25% compared with maximum lung recruitment at CDP of 45 mbar (CDP45). Data are presented as the median (25th-75th percentile); differences between measurements are determined by Friedman repeated-measures analysis on ranks and multiple comparisons (Tukey's test). The level of significance was set at P < 0.05. RESULTS: The PaO2/FiO2 ratio increased from 99.1 (56.2-128) Torr at PCV post-lavage to 621 (619.4-660.3) Torr at CDP45 (CDP45) (P < 0.031). The pulmonary shunt fraction decreased from 51.8% (49-55%) at PCV post-lavage to 1.03% (0.4-3%) at CDP45 (P < 0.05). The cardiac output and stroke volume decreased at CDP45 (P < 0.05) compared with PCV, whereas the heart rate, mean arterial pressure, and intrathoracic blood volume remained unchanged. A TPP of 25.5 (17-32) mbar was required to preserve a difference in PaO2/FIO2 ratio < 25% related to CDP45; this TPP was achieved at a CDP of 35 (25-40) mbar. CONCLUSION: This HFOV protocol is easy to perform, and allows a fast determination of an adequate TPP level that preserves oxygenation. Systemic hemodynamics, as a measure of safety, showed no relevant deterioration throughout the procedure.

Animals↗
PubMed2005

Aromatase inhibitors and cyclooxygenase-2 (COX-2) inhibitors in endometriosis: new questions--old answers?

The medical treatment of endometriosis needs to be optimized. Therapeutic management strategies for endometriosis-associated pain or recurrent disease are primarily aimed at downregulating ovarian function or antagonizing the effect of estrogen in ectopic endometrial implants. In this context, basic research is providing important results for the development of new, specific treatment modalities. Aromatase overexpression has recently been detected in endometriotic tissue. Aromatase (p450arom) is responsible for converting C19 androgens into estrogen in several types of human tissue. Aromatase activity causes local estrogen biosynthesis, which, in turn, stimulates prostaglandin E2 production by upregulating cyclooxygenase-2 (COX-2). Thus, a positive feedback cycle develops between the two systems. Another abnormality in endometriosis, the deficient 17beta-hydroxysteroiddehydrogenase type II (17beta-HSD-Type-II) expression, impairs the inactivation of estradiol to estrone. In contrast to the eutopic endometrium, these molecular aberrations increase the amount of local estradiol and prostaglandin E2 in endometriosis. In several human cell lines, prostaglandin and estrogen concentrations are associated with proliferation, migration, angiogenesis, apoptosis resistance and even invasiveness. Consequently, aromatase and COX-2 are thought to be promising new therapeutic targets. Thus, specific aromatase inhibitors (e.g. Letrozol/Femara, Anastrozol/Arimidex or Exemestan/Aromasin) or selective COX-2 inhibitors (e.g. Celecoxib/Celebrex, Rofecoxib/Vioxx, Valdecoxib/Bextra) are of great interest and should be studied in clinical trials in premenopausal woman with endometriosis to expand the spectrum of currently available treatment options.

Aromatase Inhibitors↗
PubMed2005

Comparison of isosorbide mononitrate (Mono Mack) and misoprostol (Cytotec) for cervical ripening in the first trimester missed abortion.

OBJECTIVE: The objective of this study was to compare NO-donor isosorbide mononitrate to misoprostol, both applied as vaginal tablets for cervical ripening prior to first trimester curettage in patients with missed abortion. MATERIALS AND METHODS: Thirty women with missed abortion were assigned after a random list to be treated either with 200 microg gemeprost (Cytotec, Pfizer, Germany) or with 40 mg isosorbide mononitrate for cervical priming at least 3 h before curettage. Vaginal bleeding or the intracervical presence of products of conception was documented. The largest number of Hegar's dilator, which could be introduced without difficulty and the largest number of Hegar's dilator at which cervical dilation was performed and the ease of mechanical dilation was assessed. RESULTS: There were no significant differences in cervical ripeness before procedure nor in ease of dilation. In the misoprostol group, the cervical canal was more dilated before any procedure (median of Hegar's dilator 6 vs. 5) and after dilation (median of Hegar's dilator 11 vs. 10), although this difference was not significant. Vaginal bleeding occurred in two patients in each group. Products of conception were only found in the cervix of one patient of the misoprostol group. SYNOPSIS: Vaginal application of isosorbidemononitrate in cervical priming prior to curettage abortion is as effective as vaginal application of misoprostol.

Abortifacient Agents, Nonsteroidal↗
PubMed2005

Analysis of atelectasis, ventilated, and hyperinflated lung during mechanical ventilation by dynamic CT.

STUDY OBJECTIVE: To study the dynamics of lung compartments by dynamic CT (dCT) imaging during uninterrupted pressure-controlled ventilation (PCV) and different positive end-expiratory pressure (PEEP) settings in healthy and damaged lungs. DESIGN: Experimental animal investigation. SETTING: Experimental animal facility of a university department. INTERVENTIONS: In seven anesthetized pigs, static inspiratory pressure volume curves were obtained to identify the individual lower inflection point (LIP) before and after saline solution lung lavage. During PCV, PEEP was adjusted 5 millibars (mbar) below the individually determined LIP (LIP - 5), at the LIP, and 5 mbar above the LIP (LIP + 5). MEASUREMENTS AND RESULTS: Measurements were repeated before and after induction of lung damage. Hemodynamics, arterial and mixed venous blood gases, and dCT imaging in one juxtadiaphragmatic slice (effective temporal resolution of 100 ms) were assessed during uninterrupted PCV in series of three successive respiratory cycles. The mean fractional area (FA) of the hyperinflated lung (FA-H), mean FA of ventilated lung, mean FA of poorly ventilated lung, and mean FA of nonventilated lung (FA-NV), and the change in FA of the whole lung area (DeltaFA) were compared at different PEEP settings. Calculated pulmonary shunt (Qs/Qt) was compared to FA-NV. LIP + 5 decreased the amount of atelectasis (FA-NV) and increased hyperinflation (FA-H) in healthy and injured lungs. Cyclic changes of atelectasis (DeltaFA-NV) and hyperinflation (DeltaFA-H) were observed in both healthy and injured lungs. In the injured but not in the healthy lungs, the amount of cyclic changes of atelectasis and hyperinflation were independent from the adjusted PEEP level. FA-NV correlated with the calculated Qs/Qt, with a slight overestimation (mean +/- SEM, 2.1 +/- 4.1%). CONCLUSIONS: dCT imaging allows the following: (1) the quantification of the extent of atelectasis, ventilated, poorly ventilated, and hyperinflated lung parenchyma during ongoing mechanical ventilation; (2) the detection and quantification of repeated recruitment and derecruitment, as well as hyperinflation; and (3) an estimation of Qs/Qt. dCT adds promising functional information for the respiratory treatment of early ARDS.

Animals↗
PubMed2004

Turkish and German patients' recall of diagnosis and therapy before and following informed consent.

OBJECTIVE: Adequate patient knowledge is essential for good compliance, effective doctor-patient communications and is the basis for informed consent. The purpose of the study was to examine differences in recall of informed consent procedures between patients with different ethnicity and to identify potential explanatory factors. DESIGN: We analyzed 579 patients, attending and released from a gynecology department in Berlin, Germany, between March 1997 and October 1998. To assess actual understanding of disclosure information, Turkish and German patients' perceptions were compared with documented data of their diagnoses and therapy. RESULTS: Overall, patients correctly identified 69% of their diagnosis and 76% of their therapy. On discharge overall patients' recall decreased significantly. Whereas German patients' knowledge increased, Turkish patients showed significant decreases in diagnosis and therapy recall. CONCLUSION: The results reflect socio-demographic differences between ethnic groups and indicate deficiency of the informed consent process for patients belonging to an ethnic minority.

Adult↗
PubMed2004

Risk factors for fetal-to-maternal transfusion in Rh D-negative women--results of a prospective study on 942 pregnant women.

AIMS: To investigate the incidence of severe fetal-to-maternal transfusion after delivery and to identify risk factors. MATERIAL AND METHODS: In a prospective study at the Department of Obstetrics, Charité, Campus Virchow-Klinikum, Berlin, Germany, we analyzed the incidence of severe fetal-to-maternal transfusion (>10 ml) and fetal-to-maternal hemorrhage (>25 ml) in Rh D-negative pregnant women after delivery of Rh D-positive infants. 942 women were included in the study and Kleihauer-Betke tests were performed. The results were compared to perinatal data. RESULTS: Fetal-to-maternal hemorrhage occurred in 13 cases out of 942 (incidence of 1.3%) and severe fetal-to-maternal transfusion in 61 cases (6.5%). In all of the cases with fetal-to-maternal hemorrhage, mothers were compatible with their infants in ABO-system. The incidence of fetal-to-maternal transfusion and its severe form was significantly higher in twin pregnancies (7/21 cases and 5/21 cases respectively, 33.3% and 23.8%) than in singleton pregnancies (22.5%, and 5.9%, P<0.001). All other factors, such as maternal age, parity, ethnicity, mode of delivery, presentation, duration of first and second stage of labor, CTG, or Apgar score were not associated with an increased risk of severe fetal-to-maternal transfusion. CONCLUSIONS: Twin pregnancy is the only independent risk factor for severe fetal-to-maternal transfusion. ABO-incompatibility between mother and infant seems to be protective against Rh D-alloimmunization.

ABO Blood-Group System↗
PubMed2003

High-frequency oscillatory ventilation in adult acute respiratory distress syndrome.

OBJECTIVE: This study examined whether ARDS patients in whom predefined ventilator settings fail to maintain oxygenation and CO2 removal can be safely transitioned to high-frequency oscillatory ventilation (HFOV), and whether HFOV use is efficacious. DESIGN AND SETTING: Prospective observational study in the 14-bed intensive care unit of a university hospital. PATIENTS AND PARTICIPANTS: 42 patients with ARDS (APACHE II score 28 (IQR 24-37) and ventilation time prior HFOV 3.0 days (0.7-9.1). MEASUREMENTS AND RESULTS: Gas exchange parameters and ventilator data were recorded before and during HFOV treatment (-12 h, -6 h, baseline, 10 min, 1 h, 6 h, 12 h, 24 h). Primary endpoints included: (a) PaO2/FIO2 ratio 24 h after start of HFOV treatment or the last point of measurement if HFOV ended within the first 24 h; (b) HFOV-related complications. Post hoc analysis assessed the relationship between outcome and the response to HFOV, and between outcome and time of mechanical ventilation prior to HFOV. At baseline the median PaO2/FIO2 ratio was 95 (IQR 62-129); after 24 h of HFOV the PaO2/FIO2 ratio had increased significantly to 165 (88-225); only one patient developed a unilateral pneumothorax. Of the 42 patients 18 (43%) had died by day 30. Subset analyses showed a significantly higher 30-day mortality rate in patients with at least 3 days of mechanical ventilation prior to HFOV (64%) and in patients without oxygenation improvement after 24 h on HFOV (71%). CONCLUSIONS: HFOV is an effective and safe method to ventilate ARDS patients. Failure to improve oxygenation within 24 h of HFOV is associated with high mortality.

Adult↗
PubMed2003

Focused ultrasound treatment of uterine fibroid tumors: safety and feasibility of a noninvasive thermoablative technique.

OBJECTIVE: The purpose of this study was to determine the safety and efficacy of focused ultrasound surgery with magnetic resonance imaging guidance for the noninvasive treatment of uterine leiomyomas. STUDY DESIGN: Fifty-five women with clinically significant uterine leiomyomas were treated. Pain and complications were assessed prospectively, and posttreatment magnetic resonance imaging was used to measure the treatment effects. Patients in three of the five centers underwent planned hysterectomy after treatment, which provided pathologic correlation of treatment. RESULTS: Seventy-six percent of the enrolled patients completed the full treatment session. All treatments were conducted in an outpatient setting with minimal discomfort for subjects and no major complications. Pathologic examination of the uterus confirmed that magnetic resonance imaging guidance provides the safe and accurate delivery of effective levels of thermal energy with a 3-fold increase in volume of histologically documented necrosis, compared with treatment volume (6.6 +/- 0.8 vs 18.4 +/- 3.9 mL, P <.005). CONCLUSION: Magnetic resonance imaging-guided focused ultrasound surgery appears to be a well-tolerated treatment for uterine leiomyomas.

Adult↗