Towards a farmer-feasible soil health assessment that is globally applicable.

Globally, agriculture has had a significant and often detrimental impact on soil. The continued capacity of soil to function as a living ecosystem that sustains microbes, plants, and animals (including humans), its metaphorical health, is of vital importance across geographic scales. Healthy soil underpins food production and ecosystem resilience against a changing climate. This paper focuses on assessing soil health, an area of increasing interest for farming communities, researchers, industry and policy-makers. Without accessible and reliable soil assessment, any management and interventions to improve soil health are likely to be sub-optimal. Here we explore available soil health assessments (SHAs) that may be feasible for farmers of varying income levels and suitable for broad geographic application. Whilst there is a range of existing approaches to SHA, we find that no one framework currently meets these broad aims. Firstly, reliance on expensive and logistically complex laboratory methods reduces viability and accessibility for many farmers. Secondly, lack of defined indicator baselines and associated thresholds or gradients for soil health prevents the assessment of soil measurements against achieving optima for a given set of local soil-climate conditions. Since soils vary greatly, these baselines and thresholds must be defined considering the local biogeographic context; it is inappropriate to simply transfer calibrated information between contexts. These shortcomings demand progress towards a feasible, globally applicable and context-relevant SHA framework. The most feasible SHAs we identified were developed locally in conjunction with farmers, who have been repeatedly found to assess the health of their soils accurately, often using relatively simple, observable indications. To progress, we propose assessment of which indicators add information to a SHA in local contexts, with a focus on sufficiency, to reduce data burden. Provision of a standardised protocol for measurement and sampling that considers the reliability and accuracy of different methods would also be extremely valuable. For greatest impact, future work should be taken forward through a cross-industry collaborative approach involving researchers, businesses, policy makers, and, above all, farmers, who are both experts and users.

Multimode dynamics and emergence of a characteristic length scale in a one-dimensional quantum system.

We study the nonequilibrium dynamics of a coherently split one-dimensional Bose gas by measuring the full probability distribution functions of matter-wave interference. Observing the system on different length scales allows us to probe the dynamics of excitations on different energy scales, revealing two distinct length-scale-dependent regimes of relaxation. We measure the crossover length scale separating these two regimes and identify it with the prethermalized phase-correlation length of the system. Our approach enables a direct observation of the multimode dynamics characterizing one-dimensional quantum systems.

S3-Guidelines for the Treatment of Inflammatory Breast Disease during the Lactation Period: AWMF Guidelines, Registry No. 015/071 (short version) AWMF Leitlinien-Register Nr. 015/071 (Kurzfassung).

Breastfeeding is widely acknowledged to be the best and most complete form of nutrition for healthy infants born at term and is associated with numerous benefits in terms of infants' health, growth, immunity and development. However, breastfeeding problems often result in early weaning. Standardized treatment recommendations for breastfeeding-related diseases are necessary to optimize the care offered to breastfeeding women. Evidence and consensus based guidelines for the treatment of puerperal mastitis, sore nipples, engorgement and blocked ducts were developed on the initiative of the National Breastfeeding Committee. These guidelines were developed in accordance with the criteria set up by the Arbeitsgemeinschaft der Wissenschaftlichen Medizinischen Fachgesellschaften (AWMF), the Association of Scientific Medical Societies in Germany. The recommendations were drawn up by an interdisciplinary group of experts and were based on a systematic search and evaluation of the literature but also took clinical experience into account. Additionally good clinical practice (GCP) in terms of expert opinion was formulated in cases where scientific investigations could not be performed or were not aimed for. This article presents a summary of the recommendations of the S3-guidelines.

Relaxation and prethermalization in an isolated quantum system.

Understanding relaxation processes is an important unsolved problem in many areas of physics. A key challenge is the scarcity of experimental tools for the characterization of complex transient states. We used measurements of full quantum mechanical probability distributions of matter-wave interference to study the relaxation dynamics of a coherently split one-dimensional Bose gas and obtained comprehensive information about the dynamical states of the system. After an initial rapid evolution, the full distributions reveal the approach toward a thermal-like steady state characterized by an effective temperature that is independent from the initial equilibrium temperature of the system before the splitting process. We conjecture that this state can be described through a generalized Gibbs ensemble and associate it with prethermalization.

[Changes in MR images in pre-eclampsia and eclampsia]. / MR-tomografische Veränderungen bei Präeklampsie und Eklampsie.

BACKGROUND: Pre-eclampsia affects 2% of pregnancies. This multisystem disorder is a major cause of maternal, foetal and neonatal mortality and morbidity. Neurological manifestations of eclampsia are headache, nausea, vomiting, cortical blindness and recurrent seizures. OBJECTIVE: The purpose of this study was to determine whether the neurological symptoms correlate with MR imaging findings. RESULTS: In a patient with eclamptic seizure and another one with blindness due to pre-eclampsia, the white matter hyperintensities on T (2)-weighted MR and FLAIRsequence images could be demonstrated in the occipital region and in the basal ganglia. Within 3-5 days all neurological symptoms and radiological abnormalities had resolved. CONCLUSION: These cerebral lesions could be classified as posterior reversible encephalopathy syndrome (PRES) or as reversible leukoencephalopathy syndrome (PLES). Thus, MRI supports differential diagnosis regarding non pregnancy-related cerebral disease and can be helpful for therapy planning in cases of pre-eclampsia.

The use of i. v. bisphosphonate in pregnancy-associated osteoporosis--case study.

OBJECTIVE: Diagnosis of pregnancy-associated osteoporosis is often delayed and therapeutic interventions insufficient. STUDY DESIGN: A 28-year-old patient (BMI=18.6) with no additional risks for osteoporosis experienced acute lumbosacral pain two months postpartum, while lactating. After conservative therapy, thoracic and lumbar spine were X-rayed: severe pregnancy-associated osteoporosis with vertebral fractures was diagnosed. 2-year treatment with i. v. bisphosphonate ibandronate was initiated (2 mg every 3 months) and calcium and vitamin D supplementation. RESULTS: Rapid improvement was observed. Conclusion: In cases with multiple fractures i. v. bisphosphonate leads to substantial decrease of symptoms and further fractures and significant increase of bone mass density (BMD). CONCLUSION: In severe cases of pregnancy-associated osteoporosis with multiple fractures i. v. biphosphonate therapy leads to a decrease of symptoms and fracture risk and an increase of bone mass density (BMD).

[Quality of data transfer in perinatal data -- experience of a centre]. / Ubertragungsqualität von Perinataldaten -- Erfahrungen an einem Zentrum.

BACKGROUND: A sufficient quality of data transfer from written patient records to electronic data processing is a precondition for a reasonable usage of perinatal data. However the quality of data transfer of the almost 200 characteristics routinely recorded at each delivery is largely unknown. MATERIALS AND METHODS: The quality of data transfer of 33 characteristics in 350 randomly selected singleton deliveries of the women's clinic of the University of Marburg from 2002 and 2003 has been checked by comparing electronically recorded data with the original written documents. RESULTS: The quality of data transfer of the tested characteristics turned out to be heterogeneous. Characteristics necessary to calculate quality indicators show a very high data quality when excluding the characteristic attendance of a paediatrician. The quality of data transfer of characteristics denoting time as well as blood gas analysis are heterogeneous. Characteristics with a low quality of data transfer are associated with ambiguous instructions, the fact that the coding obstetrician is not dealing in the first instance with the item being encoded and the characteristics are of no immediate relevance for delivery, as well as difficult application of the software. CONCLUSION: The quality of data transfer of the characteristics collected in perinatal surveys needs to be validated. The type and amount of data being collected should be reassessed considering improvements of data quality.

Fetal lung development in pregnancies of diabetic women assessed by quantitative ultrasonic tissue characterization.

OBJECTIVES: This study was performed to compare quantitative ultrasonic tissue characterization of the fetal lung at different gestational ages in uncontrolled diabetic patients with that in normal uncomplicated pregnancies. METHODS: A total of 44 women at 24-37 weeks' gestation with the diagnosis of diabetes in pregnancy were enrolled. Data were compared to those of the control group, which consisted of 140 women with uncomplicated pregnancies of the same gestational age. Longitudinal and transverse sections of the fetal thorax and upper abdomen were examined. A region of interest of constant size was defined and the tissue-specific gray scale was determined by using interactive software. RESULTS: Compared with normal pregnancies, fetal lungs of diabetic pregnancies have a higher echogenicity between 28 and 37 weeks of gestation. The lung mean gray values (MGV) only differed significantly between 30 and 31 weeks of gestation in the group with diabetes (P = 0.033) compared to the control group. The MGV of the liver in diabetic and normal pregnancies is similar during pregnancy, significant differences being found only at 30-31 weeks of gestation (P = 0.038). The lung-to-liver ratio in the control group showed a significant increase from 24 to 31 weeks and a slight non-significant decrease after 31 weeks. The ratio in the group with diabetes increased slightly up to week 33 and decreased slightly afterwards. CONCLUSION: Fetal lung MGV in uncontrolled diabetic pregnancies compared to that in uncomplicated pregnancies differs significantly only between 30 and 31 weeks of gestation.

[Dynamics of thrombin-antithrombin-III complex (TAT-III) and prothrombin fragments F1 + 2 during labour with and without aprotinin administration]. / Die Dynamik des Thrombin-Antithrombin-III-Komplexes und der Prothrombinfragmente F1 + 2 sub partu mit und ohne Aprotiningabe.

OBJECTIVE: The aim of this study was to determine if aprotinin could affect postpartal fibrinolysis when given at the latest 15 min before delivery and if there is a difference between normal delivery and caesarean section. Furthermore we wanted to examine if the thrombin-antithrombin-III-complex (TAT-III) and prothrombin fragments F1 + 2 changed in the peripartal period and if prethrombotic stages could be recognized. PATIENTS AND METHODS: 84 patients (15 - 44 years of age) have been examined (41 normal deliveries, 43 cesarean sections). After giving informed consent and randomization, 30 of these patients were administered 1 Mio KIE aprotinin (Trasylol(R)) at the latest 15 min before delivery (15 normal deliveries, 15 cesarean sections). The results of TAT-III, prothrombin fragments F1 + 2, factor VIII and partial thromboplastin-time (PTT) were collected shortly before and after delivery and 30 and 120 min after detachment of the placenta. RESULTS: Normal deliveries without aprotinin showed a significant increase of TAT-III and an evident increase of prothrombin fragments F1 + 2. After administration of aprotinin this increase was significantly lower. The increase of TAT-III and prothrombin fragments F1 + 2 in patients with caesarean sections was evidently lower than in normal deliveries and was not influenced significantly by aprotinin. Factor VIII and partial thromboplastin time (PTT) showed no relevant changes in all study groups. DISCUSSION AND CONCLUSION: The consumption of coagulation and fibrinolysis factors induced by delivery of the child and detachment of the placenta can be reduced after administration of aprotinin given at the latest 10 - 18 min before partus. This could be used in therapy and prophylactic treatment in high-risk patients (e. g., pre-eclampsia, HELLP syndrome, etc.).

[Tracheostoma valve with integrated cough lid for improvement of hands-free speech in laryngectomees - long term results]. / Tracheostomaventil mit integrierter Hustenklappe (Window) zur Verbesserung der fingerfreien Sprache des Laryngektomierten - Klinische Langzeitergebnisse.

BACKGROUND: Tracheostoma valves for laryngectomized patients were introduced to enable the laryngectomee after successful surgical voice restoration either by a voice prosthesis, a surgical shunt or microvascular laryngoplasty, to speak without using his fingers to close the tracheostoma. The basic principle of these aids is a mobile valve, which closes automatically at a certain air flow, directing the expired air of the lungs into the pharynx. In spite of the clear advantage of enabling a hands-free speech, the long term acceptance rate is still rather low, which is mainly caused by problems of an airtight fixation within or at the tracheostoma. Another important disadvantage of these tracheostoma valves is the necessity of removing the valve during coughing. The new tracheostoma valve "Window" (ADEVA Company, Lübeck, Germany) offers a clear improvement regarding this point. It is constructed with an additional coughing lid, which opens at a certain airflow and closes automatically after the coughing attack. After successful development and clinical testing of the new aid in 1999 and 2000, it was now the question, if the previously low acceptance rate of tracheostoma valves could be improved in the long term use by this new type of valve. PATIENTS: Within the last 4 years 70 patients were provided with the "Window" tracheostoma valve. Patients were followed up at regular intervals in order to evaluate the function, the acceptance and the durability of the new device. Additional to the clinical examination patients had to fill in a questionnaire in order to investigate the subjective estimation by each patient himself. 15 patients did not send back their questionnaire or did not fill it in correctly, 5 patients refused clinical supervision after adjustment of the device, so finally the long term use in 50 patients could be analysed. RESULTS: 82 % of the patients reported, that the coughing lid worked safely and opened immediately during the coughing attack. Most of the patients were satisfied with their device, but had nevertheless some proposals for a further improvement: although they cover the tracheostoma either with their clothes or a protection scarf, most of the patients would prefer a device which is smaller than the current model. Some patients reported on an insufficient stability of the plastic material, which led to a defect at the sliding mechanism of the coughing lid. The greatest problem regarding the regular use of the valve was - comparable to conventional tracheostoma valves - the occurrence of an air leakage around the tracheostoma. Although there are three different models of the "Window" tracheostoma valve available, only patients being fitted with the "standard-T-type" version could wear the device 10 hours a day or longer without any problems of air leakage. CONCLUSIONS: The "Window" tracheostoma valve with an integrated coughing lid provides further improvement in speech rehabilitation of laryngectomees. The actual rate of acceptance of 62 % for all "Window" patients (1 month daily use for at least 2 hours) is superior to other reports on the use of tracheostoma valves and probably caused by the additional comfort provided by the coughing lid. Another important factor for the long term use of tracheostoma valves is however the safe fixation of the device in or around the tracheostoma. In this point further improvement is necessary, as only the model with the fixation within the trachea (T-type) led to a satisfactory long term airtight fixation.

[Evaluation of the reproducibility of Doppler ultrasonographic measurements in obstetrics]. / Evaluierung der Reproduzierbarkeit dopplersonographischer Messungen in der Geburtshilfe.

BACKGROUND: Are obstetric doppler ultrasonographic measurements of the fetal and maternal flow parameters reproducible? PATIENTS AND METHODS: For internal quality management, doppler ultrasonographic measurements were performed on 81 patients (random screening sample) with an Acuson Sequoia Ultrasound at the Universitätsfrauenklinik Marburg. Successively two experienced investigators measured the umbilical artery, medial cerebral artery, and the uterine arteries. The correlation between the measurements of the two investigators was presented in a spread chart. In order to exclude systematic differences between the measurements, linear regression was analyzed and the distance to the abscissa was calculated. A relative divergence of more than 20% was determined as a non corresponding measurement. RESULTS: The distance of the linear regression to the abscissa was calculated for the four vessels: umbilical artery 0.4 (95% CI; 0.124 - 0.486), medial cerebral artery 0.9 (95% CI; 0.534 - 1.264), right uterine artery 0.2 (95% CI; 0.124 - 0.305), and left uterine artery 0.2 (95% CI; 0.121 - 0.317). Concerning the four arteries, a divergence of more than 20% between the two investigators was found: umbilical artery 16%, medial cerebral artery 42%, right uterine artery 28%, and left uterine artery 37%. CONCLUSIONS: Because the interobserver variability was surprisingly high and acceptable correlation could be stated only for the umbilical artery, internal quality standards are essential. Routine use of different devices should be made after careful consideration only, especially if clinical decisions are to be based on them.

[Changes of fibrinolysis during labour with and without aprotinin application]. / Veränderungen der Fibrinolyse während der Geburt mit und ohne Gabe von Aprotinin.

OBJECTIVE: The aim of this study was to determine (a) if alpha-2-antiplasmin, plasminogen and plasminogen-activator-inhibitors (PAI 1 - 4) change in the peripartal period, (b) if these changes are explainable by the detachment of the placenta and the release of coagulation factors, and (c) if aprotinin could affect postpartal fibrinolysis when given shortly before delivery. PATIENTS AND METHODS: 84 patients have been examined (41 normal deliveries, 43 cesarean sections). After informed consent and randomization, 30 of these patients were administered 1 million KIU aprotinin (Trasylol(R)) at the latest 15 minutes before delivery (15 normal deliveries, 15 cesarean sections). The results of PAI (1 - 4), alpha-2-antiplasmin and plasminogen were collected shortly before and after delivery and 30 and 120 min after detachment of the placenta. RESULTS: Normal deliveries and cesarean sections without aprotinin showed an evident decrease of PAI (1 - 4) after delivery while alpha-2-antiplasmin and plasminogen values did not change. After administration of aprotinin the activity of PAI (1 - 4) increased slightly after labour in normal deliveries and cesarean sections and then slowly decreased later. alpha-2-Antiplasmin levels increased post partum and then decreased to the original values. Plasminogen did not change. There were no significant differences between normal deliveries and cesarean sections with regard to the three parameters studied in this work. DISCUSSION AND CONCLUSION: Changes in PAI (1 - 4) and alpha-2-antiplasmin after administration of aprotinin could be the result of a minimal demand on the fibrinolytic system. Finally, aprotinin can reduce the consumption of coagulation and fibrinolysis factors induced by detachment of the placenta. This could be used in therapy and prophylactic treatment in high-risk patients (e.g., pre-eclampsia, HELLP syndrome, etc.).

[Fetal pulse oximetry during risk deliveries in German clinics--a representative national survey in 81 obstetric departments]. / Uber den Einsatz der fetalen Pulsoxymetrie bei Risikogeburten in deutschen Kliniken - Ergebnisse einer repräsentativen Anwenderumfrage an 81 Geburtskliniken -

BACKGROUND: The development of a new technique to evaluate the normal fetal acid-base balance in risk deliveries with pathological fetal heart rate has been seen with great expectations over the last years. The aim of this representative survey was to ask for the actual status of the fetal pulse oximetry in clinical use in German delivery rooms and to analyze hopes, expectations and system errors. PATIENTS RESPECTIVELY AND METHODS: Collecting data were done by a representative, time limited anonymous questionnaire in all German clinics who used Nellcors fetal pulse oximetry N-400 in measuring fetal arterial saturation in the years 1995 - 1999 during risk deliveries with non-reassuring fetal heart rate. RESULTS: With 66,6 % of the departments participating a number of 54 clinics returned the questionnaires. An average of 4.5 times per month fetal pulse oximetry was used per clinic and in over 90 % of all cases the handling and fixation of the sensor was without problems. There is qualified staff in every clinic and regarding the satisfaction with this system an average note of 2.8 was assigned. Fetal pulse oximetry will be established in some years to replace fetal blood analysis and to reduce operative deliveries. Technical problems in cases of insufficient sensor fixation at the fetal head and with the re-sterilization of fetal sensors must be solved in the future. CONCLUSIONS: Fetal pulse oximetry will be incorporated as the third method of monitoring the fetus during labor.

[Effect of modified labor posture on oxygenation of the fetus--a pulse oximetry study]. / Der Einfluss einer modifizierten Gebärhaltung auf die Oxygenierung des Feten--Eine pulsoxymetrische Untersuchung.

BACKGROUND: The evaluation of the birth position and its effects on maternal and fetal wellbeing has been a topic of perinatal research over the last decades. The aim of our observational study was to determine the effects of a modified and vertical maternal position on fetal oxygen saturation measured by pulse oximetry. METHODS: Fetal oxygen saturation was measured by pulse oximetry in 56 labouring women randomly and successively adopting the supine position in 96.4%, the sitting position in 25.0%, the standing position in 14.3% and the prone position in 12.5%. The statistical analysis addressed the integrated 10 minutes period of SpO2 registrations before versus after adopting the modified position. Furthermore the mean values and the standard deviation (SD) for the total registration periods of different birth position was calculated. RESULTS: While the supine position induced a reduction in oxygen saturation, sitting and prone position were favorable for fetal oxygenation as compared to horizontal position. DISCUSSION: These findings implicate a clinical benefit of the modified birth position.

24 hour-CTG monitoring: comparison of normal pregnancies and pregnancies with placenta insufficiency.

AIMS: Routinely antepartal CTG will be recorded for 30 minutes to obtain normal resting phases, a decrease of irregulatory due to hypoxia or to differentiate these from each other. In case of early onset of hypoxia first pathological findings might only be seen by chance in incidentally recorded CTG. The goal of this study was, if a continuous 24 hour-CTG will allow an earlier detection of beginning hypoxia in case of placental insufficiency compared to a routine CTG of 30 minutes. METHODS: 21 normal pregnancies and 17 patients with placental insufficiency of > or = 36 weeks had 24 hour-CTG's by means of telemetry. In both study groups fetal heart rate (FHR) tracing included a full qualitative and quantitative description. Comparison of the results of both groups was done to look for early signs of pathological findings concerning reduced fetal well-being. RESULTS: In comparison to normal pregnancies patients with placental insufficiency had in 4.5% oscillation frequency type A and an increase of saltatory and silent oscillation. The number of accelerations and Dip 0 was significantly reduced as well as accelerations in combination with undulatory oscillation. Baseline tachycardia and bradycardia showed significantly increasing quantity. CONCLUSIONS: 24 hour-CTG is a good screening method to detect early onset of hypoxia in case of beginning placental insufficiency. The failure to find any clinically significant difference in the diurnal variation of both groups suggests, that less than 24 hour testing is required. 8 hour-CTG could be a compromise and a big help to detect a fetus at risk earlier.

Changes in lymphocyte subsets during pregnancy and post-partum in cases of beginning eclampsia.

AIMS: The goal of the present retrospective study was to examine the peripheral blood lymphocytes for expression of phenotypic and activation markers concerning the development of hypertension in pregnancy. METHODS: 16 women (aged 25-43 years; mean 35.1) developing hypertension in the third trimester (week 25-34) have had blood samples taken in the first (< 14 weeks), the second (week 14-23), the third trimester (week 24-35), in late pregnancy (week 36-termination of pregnancy) and within 1 week post-partum, The control group consisted of 16 age-matched pregnant healthy women, who underwent the same regime. All blood samples were taken in the morning, stored at room temperature and stained within 6 hours and measured within 24 hours. Kruskal-Wallis analysis of variance between both groups was done with multiple comparison according to Dunn. RESULTS: Comparing both groups, the total white cell count was significantly increased in all pregnancies and post-partum. In case of hypertension in pregnancy the cell numbers of suppressor/cytotoxic (CD 8+) and CD 56(+)-activated T cells showed a significant increase in the first trimester (< 14 weeks) [p < 0.05] and decreased thereafter to normal values. In the second trimester (week 14-23) helper/inducer lymphocytes and CD 56+/CD 3+ lymphocytes decreased in case of pre-ecclampsia and cytotoxic lymphocytes elevated [p < 0.05]. In the third trimester (week 24-35) there was no difference in both study groups and in late pregnancy (week 36-termination) there were only small differences without statistical significance. Within 1 week postnatal the value of Il-2 receptor T lymphocytes decreased in the group of pre-eclampsia in comparison to normal pregnancies [p < 0.05]. CONCLUSIONS: Regarding the major changes in activated T cells in both study groups no specific pattern of lymphocyte subsets in case of pre-eclampsia could be found in comparison to healthy pregnant women. Further investigations should focus on functional activation and/or suppression of the cellular immune system. Perhaps this could lead to a screening test for pre-eclampsia in future, which is non-invasive for the patient and economic for our social community because it might reduce medical costs.

[Detection of fetal cells in maternal blood with magnetically activated cell sorging (MACS) and EGF receptor antibody MAb 425]. / Nachweis von fetalen Zellen im mütterlichen Blut mittels Magnetic-activated Cell Sorting (MACS) und EGF-Rezeptor-Antikörper MAb 425.

BACKGROUND: In this study separation and enrichment of fetal trophoblastcells have been investigated in venous blood of pregnant women, in order to see, if this non-risk method can replace invasive methods of gaining fetal cells for antenatal diagnosis. MATERIAL AND METHODS: First investigation of antigen-patterns of fetal cells, placenta-tissue and leucocytes as well as of different MAb 425-concentrations in chorioncells, A-431-cells and leucocytes was done, thereafter staining of A 431-cells, staining and evidence of A 431-leucocytes mixtures (group 1: n = 11), staining of chorioncells, staining and evidence of chorioncell-leucocytes mixtures (group 2: n = 13), staining and evidence of leucocyctes of nonpregnant (group 3: n = 18) and pregnant women (group 4: n = 6). A FACScan was used. Antigen patterns of fetal cells, placenta tissue and leucocytes were tested by means of specific antibodies. RESULTS: Almost all chorioncell-cultures have been EGF-receptor positive, whereas leucocytes were negative. For separation of trophoblastcells the EGF-receptor was the most suitable. 18 leucocyte samples of non-pregnant and 6 of pregnant women were tested. There were no significant differences either concerning staining with MAb 425 or in evidence in the MiniMACS. In pregnant women there was no sufficient number of EGF-receptor-positive cells available, in order to recognize, if these cells were of fetal origin. CONCLUSIONS: Before trophoblastcells could be used for antenatal diagnosis potential influences concerning presence time and separation of these cells should be investigated. DISCUSSION: We did not have enough fetal cells for further cytogenetic investigations. One reason for not enough evidence of fetal cells could be a lack of capacity of the MiniMACS. There were probably none or not enough trophoblastcells in the maternal blood. Which parameters could be of influence, is not yet known.

The prediction of fetal acidosis by means of intrapartum fetal pulse oximetry.

OBJECTIVES: The study's objectives were to verify a threshold value for fetal arterial oxygen saturation as the critical boundary for fetal compromise during labor and to investigate a method of predicting acidosis caused by hypoxemia. STUDY DESIGN: In a multicenter study involving 3 German obstetric centers, a total of 400 deliveries were monitored by fetal pulse oximetry (Nellcor-Puritan-Bennett Model N-400 Oxygen Saturation Monitor and FS-14 Sensor; Nellcor, Inc, Pleasanton, Calif). The durations of low (60%) fetal arterial oxygen saturations during the measurement were compared between neonates with a pH <7.15 versus >/=7.15 and a base excess <-12 mmol/L versus >-12 mmol/L in the umbilical artery post partum and in neonates with an Apgar score <7 versus >/=7 by Mann-Whitney U test. In 121 of the pulse oximetry measurements the durations of low, medium, and high fetal arterial oxygen saturations were measured from one fetal scalp blood sampling to the next and correlated with the change of scalp blood pH between samplings. Multiple regression analysis was performed to estimate the expected change of pH between 2 fetal scalp blood samplings, and receiver operating characteristic analysis was done to define a minimum duration of low fetal arterial oxygen saturation values to exclude or predict a significant decline of pH. RESULTS: Neonates with a 1-minute Apgar score <7 differed from those with 1-minute Apgar score >/=7 significantly in the duration of low fetal arterial oxygen saturation but not in the durations of medium and high fetal arterial oxygen saturations. The duration of low fetal arterial oxygen saturation had been significantly longer in children with pH <7.15 or base excess <-12 mmol/L in the umbilical artery compared with those with a pH >/=7.15 or base excess >/=-12 mmol/L. The duration of high fetal arterial oxygen saturation was significantly shorter for children with a pH <7.15 or base excess <12 mmol/L than for those with a pH >/=7.15 or base excess >/=12 mmol/L. There was no difference in the groups with respect to the duration of medium fetal arterial oxygen saturation values. The duration of low fetal arterial oxygen saturation proved to be the best predictor of a decline of scalp pH between 2 fetal scalp blood samples. The pH declined significantly with a longer duration of low fetal arterial oxygen saturation (0.02 per 10 minutes). No decrease of pH by more than 0.05 was observed unless fetal arterial oxygen saturation had remained at /=10 minutes. CONCLUSION: An arterial oxygen saturation of 30% was confirmed as the critical boundary for fetal compromise during labor. The development of acidosis seems to be predictable by the duration of hypoxemia, as indicated by fetal arterial oxygen saturation