Erythropoietic quality of maternal milk.
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Erythropoiesis↗
Biomedical subjects
R Huch
Publications and source records attributed to R Huch.
Unrecognised iron deficiency in critical illness.
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Anemia, Iron-Deficiency↗
[Anemia in pregnancy].
Pregnancy and postpartum anaemia occurs worldwide, particularly in developing countries where it accounts for substantial maternal and infant morbidity and mortality. The main cause is iron deficiency, primarily of dietary origin: 20% of the world population are estimated to have some degree of trace element deficiency. Even in industrialized countries iron deficiency anaemia is common in pregnancy due to the negative iron balance created by the high fetal demand for iron. It is compounded by blood loss during and after delivery, particularly in the absence of adequate prevention and treatment. The main effects of pregnancy and postpartum anaemia (defined by the WHO as hemoglobin values < 110 g/l and < 100 g/l, respectively) present for the mother an increased susceptibility to infection and premature delivery and for the baby intrauterine growth retardation and the consequences of prematurity. Diagnosis and differential diagnosis are thus a major obstetric concern. Iron deficiency can be particularly difficult to diagnose in postpartum anaemia because ferrritin is often falsely elevated due to concurrent infection. Prevention with oral iron + folic acid supplementation has proven effective, as has intravenous iron in more severe cases, while the addition of recombinant erythropoietin augments the effect of iron alone.
Anemia, Iron-Deficiency↗
Failure to demonstrate postpartum functional iron deficiency using quantitative red blood cell analysis.
OBJECTIVE: The aim of this prospective study was to assess erythropoiesis and test for functional iron deficiency in the postpartum period using quantitative red blood cell analysis. STUDY DESIGN: Parameters were determined on admission for delivery and postpartum from 82 obstetric patients at Zurich University Hospital: full blood count, hypochromic and microcytic red cells, reticulocyte count (including subsets), reticulocyte mean corpuscular volume, reticulocyte mean hemoglobin content and reticulocyte mean corpuscular hemoglobin concentration. RESULTS: Microcytic cells increased from 0.9% prepartum to 1.4% on day 42 postpartum; hypochromic cells decreased from 4.3 to 1.9%; reticulocyte mean corpuscular volume decreased from 134 to 125 fl; reticulocyte mean hemoglobin content was unchanged. CONCLUSION: To our knowledge, this is the first medium scale application of quantitative red blood cell analysis to normal pre- and postpartum women. Our data show no evidence of functional iron deficiency or increased erythropoiesis in the postpartum period.
Adult↗
Use of 3D ultrasound as a new approach to assess obstetrical trauma to the pelvic floor.
OBJECTIVE: To determine whether 3D ultrasound examination of pelvic floor anatomy after vaginal delivery allows detection of childbirth trauma. STUDY DESIGN: Pelvic floor anatomy was examined in 16 women during the puerperium with a 3D transrectal ultrasound probe. Images were acquired via the vaginal route for the assessment of anal morphology and the transrectal route to determine paravaginal fixation. Images of the anterior pelvic floor were calculated from the information stored in the volume block. Paravaginal defect is defined as a descent of the lateral vaginal wall below the suburethral vagina, whereas sphincter defects are characterised as thinning, or as gap formation of the anterior part of the internal anal sphincter. RESULTS: This new approach allowed the examination of a horizontal plane through the urethra and the periurethral tissue which is inaccessible with 2D ultrasound techniques. Morphology of the normal and traumatised anal sphincter could be demonstrated using reference planes perpendicular to the anal canal. CONCLUSIONS: Whereas in the past, defects of the vaginal attachment to the pelvic side wall could not be examined sonographically, 3D ultrasound can now be used to examine pelvic floor anatomy and to detect changes associated with trauma to the pelvic floor following vaginal delivery.
Fecal Incontinence↗
Fetal ultrasound biometry: 1. Head reference values.
OBJECTIVE: To create reliable reference ranges and calculate Z scores for fetal head ultrasound biometry using a large sample size which is evenly distributed from 12 to 42 weeks of pregnancy. DESIGN: A prospective, cross-sectional study. SETTING: Obstetric clinics (outpatient and delivery units) at the University Hospital of Zurich. SAMPLE: The study data were obtained from 6557 pregnant women. METHODS: Only the first ultrasound examination between 12 and 42 weeks of each fetus with exactly established gestational age was used for analysis. No exclusions were made on the grounds of small-for-date birthweight, prematurity or other events several weeks after the examination. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each parameter. RESULTS: A total of 6217 fetal head biparietal diameters and 5510 occipito-frontal diameters were measured. Both head circumference and cephalic index were derived in 5462 cases where both biparietal diameter and occipito-frontal diameter could be measured on the same fetus. The centile charts, tables and regression formulae for biparietal and occipito-frontal diameters, head circumference and cephalic index are presented. An application to calculate Z scores was developed using Excel (Microsoft Corporation, USA) and macros are presented in detail in the Figure 8 footnote. The comparison of our charts with those of the two most recent studies revealed almost no differences in biparietal diameter centiles. In one publication, occipito-frontal diameter charts, and in another, head circumference charts were different from the current study. CONCLUSIONS: We have presented centile charts, tables and regression formulae for fetal head ultrasound biometry derived from a large and minimally selected sample size in a carefully designed cross-sectional study. Complete tables and regression formulae to calculate reference ranges and Z scores are presented for use in computer-aided evaluation of fetal ultrasound biometry.
Adult↗
Fetal ultrasound biometry: 2. Abdomen and femur length reference values.
OBJECTIVE: To create reliable reference ranges and calculate Z scores for fetal abdomen and femur ultrasound biometry using a large sample size which is evenly distributed from 12 to 42 weeks of pregnancy. DESIGN: A prospective, cross-sectional study. SETTING: Obstetric clinics (outpatient and delivery units) at the University Hospital of Zurich. SAMPLE: The study data were obtained from 6557 pregnant women. METHODS: Only the first ultrasound examination between 12 and 42 weeks of each fetus with certainly established gestational age was used for analysis. No exclusions were made on the grounds of small-for-date birthweight, prematurity or other events several weeks after the examination. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each parameter. RESULTS: A total of 5807 mean abdominal diameters and abdominal circumferences were derived from fetal transverse and anterio-posterior fetal abdominal diameter measurements. Fetal femur length was measured in 5860 instances. The charts, tables and regression formulae of the biometrical measurements are presented. A comparison of our charts with others showed no significant difference. Only Merz's centiles for abdominal biometry were lower and for femur length higher than ours. An application to calculate Z scores was developed using Excel (Microsoft Corporation, USA); the macros are presented in detail in the Figure 6 footnote. CONCLUSIONS: We have presented centile charts, tables and formulae for fetal abdominal diameter and circumference and femur length derived from a large and minimally selected sample size in a carefully designed cross-sectional study. Complete tables and regression formulae to calculate reference ranges and Z scores are presented to use in computer-aided evaluation of fetal ultrasound biometry.
Abdomen↗
[Air travel in pregnancy].
Women who fly during pregnancy, whether as passengers or crew, continue to fuel the debate over the potential impact on pregnancy outcome and fetal development, the two risk factors most commonly invoked being relative hypoxaemia due to the decreased cabin pressure and, more recently, cosmic radiation. On both theoretical and experimental grounds (altitude physiology and studies in pregnant women during flight), commercial flight poses no threat to the fetal oxygen supply in a normal pregnancy. As for cosmic radiation, only theoretical estimates are available of flight crew exposure: if annual doses approximate to background at ground level (3-5 mSv), the dose received during an individual pregnancy can be estimated from the fraction of annual flight time spent while pregnant. It is doubtful whether any epidemiological study could ever confirm or refute this theoretical estimate of a low increase in risk. Many airlines have opted to allow pregnant crew to continue flying. There is thus little if any ground for advising against passenger flight in pregnancy. Flying is probably the safest and most comfortable way to travel long-distance in pregnancy. The few relative contraindications include flying close to term, a history of miscarriage and premature delivery, heavy smoking, severe anemia, cardiopulmonary disease, and a serious fear of flying.
Aircraft↗
Reflectance pulse oximetry--principles and obstetric application in the Zurich system.
Transmission and reflectance are the two main modes of pulse oximetry. In obstetrics, due to the absence of a transilluminable fetal part for transmission oximetry, the only feasible option is the reflectance mode, in which sensor and detector are located on the same surface of the body part. However, none of the reflectance pulse oximeters developed for intrapartum use are fully satisfactory, as indicated by the fact that none have entered routine use. We have designed, developed, constructed and tested a reflectance pulse oximeter with the possibility to adjust the electronic circuits and signal processing in order to determine the effects of various parameters on signal amplitude and wave-form and to optimize the sensitivity and spatial arrangement of the optical elements. Following an explanation of the principles of reflectance pulse oximetry, we report our experience with the design, development, construction and field-testing of an in-house reflectance pulse oximetry system for obstetric application.
Adult↗
Pulsatility index in the fetal anterior tibial artery during the second half of normal pregnancy.
The objective of this prospective study was to establish reference values for the pulsatility index in the fetal anterior tibial artery during the second half of pregnancy. Pulsed Doppler waveform analysis of 203 fetuses at 23-42 weeks of pregnancy was performed, each fetus being examined just once. There were neither fetal nor maternal complications detectable at the time of the examination. In the first 14 fetuses from which recordings were taken, Doppler examination was performed on both fetal legs in order to evaluate systematic differences between the right and left legs. Intraobserver variability was analyzed by repetition of the measurements by the same examiner in the first 130 cases. There was no difference between right and left tibial circulation. The repeatability coefficient, defined as the 95% range for the difference in two repeat measurements, was 1.08. The pulsatility index of the anterior tibial artery (50th centile) increased slightly from 3.29 at 23 weeks of pregnancy to 4.09 at 42 weeks. The 5th and 95th centiles were calculated, as was the 95% confidence interval of the 5th and 95th centiles. Examination of the fetal peripheral circulation during the second half of pregnancy is possible with a high degree of precision. Whether there are changes in peripheral arterial circulation in compromised fetuses remains to be evaluated.
Female↗
[Effect of continuous intravenous tocolysis with beta 2-mimetics and magnesium sulfate on erythropoietin level].
14 pregnant women receiving continuous intravenous tocolysis for threatened miscarriage were studied for an effect of beta 2-mimetics on erythropoiesis in humans. After tocolytic therapy for 48 h, the hematokrit fell by 14%; conversely erythropoietin levels rose by 88.7%. Increased erythropoiesis was reflected in increased reticulocyte (and reticulocyte subpopulation) counts. There was a significant correlation between cumulative tocolytic dose and erythropoietin elevation at 48 h. The hypervolemia evidenced by the decreased hematocrit was due to the increased oral fluid intake and fluid retention, and was the presumed main cause of the elevated erythropoietin levels. This effect could enhance understanding of the control of erythropoietin secretion. A similar mechanism may account for the increase in erythropoietin levels in pregnancy.
Adult↗
Lethal multiple pterygium syndrome: suggestion for a consistent pathological workup and review of reported cases.
We report on 2 brothers with lethal multiple pterygium syndrome (LMPS) born to non-consanguineous parents as late spontaneous abortions. Both fetuses presented with massive nuchal edema, and facial anomalies including cleft palate and broad ribs. Apparently, several subgroups of LMPS exist. Differentiation is difficult, as there is no consistent agreement on a workup protocol for autopsies. We compared the findings in the literature on cases with LMPS, and we suggest a standardized workup as an initial step for more efficient differentiation between various subgroups.
Abnormalities, Multiple↗
Successful treatment of fetal megavesica in the first half of pregnancy.
OBJECTIVE: Our goal was to assess fetal kidney function in fetuses with megavesica diagnosed during the first half of pregnancy before treatment. STUDY DESIGN: In a prospective interventional study 9 fetuses with megavesica diagnosed during the first half of pregnancy underwent vesicocentesis. Fetal urine biochemical markers (urine electrolytes, osmolarity, and beta 2-microglobulins) were determined after diagnostic vesicocentesis of the fetal megavesica. RESULTS: Surprisingly, in four fetuses who underwent sampling at 13 to 18 postmenstrual weeks, vesicocentesis proved both diagnostic and therapeutic. Pregnancy proceeded with normal amniotic fluid volume, a normal-sized urinary bladder with normal dynamics, and normal postnatal renal function. A fifth fetus had trisomy 18. In three of the remaining four fetuses in whom sampling was performed at 16 to 20 postmenstrual weeks, biochemical markers indicated a poor prognosis. In the remaining fetus marginal results of biochemical studies prompted intrauterine treatment, but death from respiratory problems ensued after premature delivery at 31 weeks. CONCLUSIONS: Fetal megavesica in the first half of pregnancy is an indication for an immediate diagnostic vesicocentesis. This is the first report emphasizing early diagnosis of fetal megavesica with subsequent fetal vesicocentesis and demonstrating that this minimally invasive procedure can be life-saving if performed in early pregnancy.
Abdominal Muscles↗
Intrapartum reflectance pulse oximetry: effects of sensor location and fixation duration on oxygen saturation readings.
OBJECTIVE: To determine the effects of sensor location and suction fixation duration on measurements of intrapartum fetal oxygen saturation (SpO2) with a new reflectance pulse oximetry system. DESIGN: Fetal SpO2 values (n = 18) were determined in the first stage of labor before and after moving the sensor to another part of the fetal head. RESULTS: Mean fetal SpO2 values did not differ with sensor location (95% CI: -3.59 to 1.48). The duration of measurement period 1, before moving the sensor, was 104 +/- 44 (range 30-240) min. No time-dependent changes in SpO2 values were seen (r = 0.17). CONCLUSION: Suction is an effective and noninvasive method of securing the reflectance pulse oximetry sensor to the fetal head in the first stage of labor and does not interfere with reproducible SpO2 values over several hours.
Adult↗
Reference resistance indices of the umbilical, fetal middle cerebral and uterine arteries at 24-42 weeks of gestation.
The objective of this cross-sectional study was to construct new reference ranges for Doppler flow velocity waveform resistance indices for the fetal umbilical artery, middle cerebral artery, placental and non-placental uterine arteries and the placentocerebral ratio in a large and minimally selected population attending a single clinic. Study design and data analysis adhered to a number of stringent and validated methodological recommendations derived both from the recent literature and from a review of earlier publications in this field. The final database comprised initial routine Doppler velocimetry at 24-42 weeks' gestation in 1675 pregnancies. Separate regression models were fitted to estimate the mean and standard deviation at each gestational age for each vessel. New charts, centile tables and regression equations are presented for the resistance indices of the fetal umbilical artery, middle cerebral artery, placental and non-placental uterine arteries and the mean of both uterine arteries and for the placentocerebral ratio.
Adult↗
Diaphragmatic defects, limb deficiencies, and ossification defects of the skull: a distinctive malformation syndrome.
We report on prenatal and postnatal findings in 4 consecutive fetuses with a pattern of severe congenital anomalies who were born to a healthy nonconsanguineous couple. The spectrum of malformations includes diaphragmatic defects, hypoplastic lungs, omphalocele, limb deficiencies, syndactyly of toes, and ossification defects of the skull. This specific spectrum of anomalies is not fully compatible with that of any established syndrome. No prenatal exposure to any possible teratogen was found. Family history is suggestive for autosomal recessive inheritance, even though germ-line mosaicism in one of the parents cannot completely be excluded.
Abnormalities, Multiple↗
Physical activity at altitude in pregnancy.
Advice to pregnant women wishing to exercise at altitude is based only on isolated observations and a handful of systematic studies, none of which have explored the limits of combined exercise and altitude exposure in human pregnancy (ie, at maximal exercise and maximal altitude). Guidelines must therefore be based on a variety of sources, including the physiology of permanent residence at high altitude, in particular the degree of (and hence requirement for) adaptations specific to pregnancy over and above simple altitude acclimatization, and data from the few systematic studies in human pregnancy under conditions of short-term altitude exposure with or without exercise. Because the effects of altitude and exercise may be synergistic rather than additive, and because individual altitude tolerance and exercise capacity cannot be reliably determined at sea level, advice should err on the side of caution by not allowing for the substantial safety margins by which pregnancies are probably protected. An altitude of 2,500 m (8,250 ft) should not be exceeded in the first 4 to 5 days of short-term exposure. If exercise is performed directly after exposure, this should take place at correspondingly lower altitude, especially in the first few days. Compounding risks, eg, maternal smoking, anemia or fetal growth retardation, must be carefully excluded.
Adaptation, Physiological↗
Optimal timing of repeated rh-erythropoietin administration improves its effectiveness in stimulating erythropoiesis in healthy volunteers.
We studied the effect of recombinant human erythropoietin (rhEPO) on erythropoiesis when given at different time intervals to healthy adults. 15 volunteers were randomly selected to receive rhEPO (2 x 300 U/kg) and parenteral iron (2 x 200mg) either within a 24 h or 72 h interval. Controls received parenteral iron only. Maximum EPO levels were found 24 h after the first intravenous injection (day 1) with a mean value of 364 and 390 U/l for the rhEPO-treated groups. When second rhEPO administration was after 72 h (group III), volunteers showed significantly higher absolute reticulocyte counts and a higher percentage of young RNA-rich reticulocytes (HFR ratio) over several days compared to those who received rhEPO within a 24 h interval (group II). Both rhEPO-treated groups showed an increase in the mean reticulocyte cell volume. Reticulocyte haemoglobin concentration was inversely correlated with the increasing cell size with a nadir on day 8. Reticulocyte haemoglobin content showed a significant decrease in group II after day 5. Serum ferritin levels showed an inverse pattern to the rate of erythropoiesis. After an initial rise, the serum ferritin decrease was most pronounced in group III. Contrary to previous reports with oral iron supplementation, functional iron deficiency was not seen during rhEPO stimulation, due to parenteral iron administration. Our data suggest that the time has interval between repeated administrations of rhEPO has an important influence on its pharmacodynamics. rhEPO given within an interval of 72 h was more effective in stimulating erythropoiesis than administration within 24 h interval for the same total dose.
Adult↗