Prediction of adverse perinatal outcome by cerebroplacental ratio in women undergoing induction of labor

OBJECTIVE

To investigate the performance of screening for adverse perinatal outcome by the cerebroplacental ratio (CPR) measured within 24 h prior to induction of labor.

METHODS

This was a prospective observational study of 1902 singleton pregnancies undergoing induction of labor at ≥ 37 weeks' gestation. Doppler ultrasound was used to measure the pulsatility index (PI) in the umbilical artery (UA) and fetal middle cerebral artery (MCA) within 24 h before induction of labor. The measured UA-PI and MCA-PI and their ratio were converted to multiples of the median after adjustment for gestational age. Univariable and multivariable logistic regression analysis was used to determine whether CPR improved the prediction of adverse perinatal outcome provided by maternal characteristics, medical history and obstetric factors. The detection rate (DR) and false-positive rate (FPR) of screening by CPR were estimated for Cesarean section for presumed fetal distress and adverse neonatal outcome, which included umbilical arterial or venous cord blood pH ≤ 7 and ≤ 7.1, respectively, 5-min Apgar score < 7, admission to the neonatal intensive care unit for > 24 h or hypoxic ischemic encephalopathy.

RESULTS

A combination of maternal and pregnancy characteristics, including age, weight, racial origin, previous obstetric history, pre-eclampsia, gestational age at delivery and amniotic fluid volume, identified 39% of pregnancies requiring Cesarean section for fetal distress at a FPR of 10%; addition of CPR did not improve the performance of screening. In screening for adverse neonatal outcome by a combination of parity and CPR, the DR was 17% at a FPR of 10%.

CONCLUSION

Low CPR, measured within 24 h prior to induction of labor, is associated with increased risk of Cesarean section for fetal distress and adverse neonatal outcome, but the performance of CPR for such surrogate measures of fetal hypoxic morbidity is poor. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Preventing deaths from complications of labour and delivery

The process of labour and delivery remains an unnecessary and preventable cause of death of women and babies around the world. Although the rates of maternal and perinatal death are declining, there are large disparities between rich and poor countries, and sub-Saharan Africa has not seen the scale of decline as seen elsewhere. In many areas, maternity services remain sparse and under-equipped, with insufficient and poorly trained staff. Priorities for reducing the mortality burden are provision of safe caesarean section, prevention of sepsis and appropriate care of women in labour in line with the current best practices, appropriately and affordably delivered. A concern is that large-scale recourse to caesarean delivery has its own dangers and may present new dominant causes for maternal mortality. An area of current neglect is newborn care. However, innovative training methods and appropriate technologies offer opportunities for affordable and effective newborn resuscitation and follow-up management in low-income settings.

[Birth hypoxia]

OBJECTIVE

Evaluation of the commonly used laboratory and clinical parameters of the newborn shortly after birth. Check thresholds acidemia, and in relation to the method of termination of pregnancy.

DESIGN

Retrospective epidemiological study.

SETTING

Department of Obstetrics and Gynecology, University Hospital, Olomouc.

METHODS

Of the 26,869 children born in the years 2000 to 2013 Inclusion criteria (complete clinical and laboratory findings after birth) fulfill 23,471 (87.4%) neonates. Methods for evaluation of newborns included Apgar score calculation and arterial umbilical cord blood pH and lactate analysis.

RESULTS

A total of 0.7% (157) of the neonates had severe acidosis pH below 7.00 arterial umbilical cord blood, its prevalence varies annually between 0.1 to 1.1%. Cutoff lactate in relation to pH < 7.00 was 6.3 mmol/l (n = 23 471, the sensitivity of 92.99%, specificity 92.15%, AUC = 0.972). For children of low weight < 2500 g the cutoff value is lower, 5.3 mmol/l (n = 2592, 89.66% sensitivity, specificity 91.10% AUC = 0.912). Suprathreshold lactate values was 8.4% (1977) newborns. Correlation of pH and lactate to Apgar evaluation is very low and in the range from 1 to 10 minutes gradually decreases. Worse Apgar evaluation in children of low birth weight do not correspond to laboratory findings acidosis, which is probably related to prematurity and lower energy reserves. Operating cesarean births in particular accounts for more than half of those with worse clinical findings Apgar and pH <7.00, but only 30% supratreshold lactate values. Also worse clinical evaluation after caesarean section is not in accordance with the laboratory findings. Vaginal surgery, especially forceps have a significant share of severe acidosis than cesarean, regardless of their frequency. Risk factor of forceps to pH less 7.00,OR = 9.28 (5.39 -15.77), P = 0.0000000, while caesarean to pH less 7,00 had OR = 1.52 (1.08 to 2.14), P = 0.01408156.

CONCLUSION

The results obtained confirm that acidosis after birth is quite common, although they may not have response on the clinical condition of the newborn after birth. Evaluation of Apgar is little objective for the detection of hypoxia during birth and is influenced by the immaturity of newborn and method of delivery. Lactate levels may contribute to an objective assessment of hypoxia during birth. Values above 6.3 mmol/l can be considered an important indicator of newborn acidosis and birth hypoxia.

Trends in the use of preconditioning to hypoxia for early prevention of future life diseases

Environmental factors during fetal life program the health outcomes regarding many diseases in future life. This idea has been supported by worldwide epidemiological studies, but the underlying mechanisms are still poorly understood. Three questions should be answered. (i) Does a common underlying cause of ordinary pathological fetal development exist? (ii) If such a cause exists, which mechanism might develop disease in later life? (iii) Is it possible to prevent this underlying cause and therefore the associated obstetric complications to primarily prevent future life diseases? The objective of this review is to attempt to answer these three questions by using PubMed (extending to October 2012) and other sources. Three data-based answers corresponding to these questions were found: (i) hypoxia, (ii) excessive stimulation of neurogenesis, and (iii) preconditioning/adaptation to hypoxia. The method for such preconditioning/adaptation is intermittent hypoxic training (IHT), in which air with low oxygen concentration is breathed through a mask to protect against subsequent strong adverse influences. Data are cited for IHT applications for the prevention/treatment of diseases in different fields, particularly in obstetrics. Data suggested that all common fetal origins of adult diseases are likely predetermined by changes in the fetal brain; therefore, early detection of these changes must be very important. The use of IHT may be a real means to primarily prevent obstetric complications and therefore, prevent future life diseases.

Cellular biology of end organ injury and strategies for prevention of injury

The interruption of placental blood flow induces circulatory responses to maintain cerebral, cardiac, and adrenal blood flow with reduced renal, hepatic, intestinal, and skin blood flow. If placental compromise is prolonged and/or severe, total circulatory failure is likely with cerebral hypoperfusion and resultant hypoxic ischemic cerebral injury with collateral renal, cardiac, and hepatic injury. Management strategies should be targeted at restoring cerebral perfusion and oxygen delivery and minimizing the extent of secondary injury. Specifically, the focus should include the judicious use of supplemental oxygen, avoidance of hypoglycemia and elevated temperature in the delivery room, and the early administration of therapeutic hypothermia to high-risk infants.

A maternal diet supplemented with creatine from mid-pregnancy protects the newborn spiny mouse brain from birth hypoxia

The creatine-phosphocreatine shuttle is essential for the maintenance of cellular ATP, particularly under hypoxic conditions when respiration may become anaerobic. Using a model of intrapartum hypoxia in the precocial spiny mouse (Acomys cahirinus), the present study assessed the potential for maternal creatine supplementation during pregnancy to protect the developing brain from the effects of birth hypoxia. On day 38 of gestation (term is 39 days), the pregnant uterus was isolated and placed in a saline bath for 7.5 min, inducing global hypoxia. The pups were then removed, resuscitated, and cross-fostered to a nursing dam. Control offspring were delivered by caesarean section and recovered immediately after release from the uterus. At 24 h after birth hypoxia, the brains of offspring from dams fed a normal diet showed significant increases in lipid peroxidation as measured by the amount of malondialdehyde. In the cortical subplate, thalamus and piriform cortex there were significant increases in cellular expression of the pro-apoptotic protein BAX, cytoplasmic cytochrome c and caspase-3. When pregnant dams were fed the creatine supplemented diet, the increase in malondialdehyde, BAX, cytochrome c and caspase 3 were almost completely prevented, such that they were not different from control (caesarean-delivered) neonates. This study provides evidence that the neuroprotective capacity of creatine in the hypoxic perinatal brain involves abrogation of lipid peroxidation and apoptosis, possibly through the maintenance of mitochondrial function. Further investigation into these mechanisms of protection, and the long-term development and behavioural outcomes of such neonates is warranted.

Long-distance relay transportation of a patient with twin-twin transfusion syndrome requiring early delivery by Doctor-Helicopters

In Japan, there has recently been a severe shortage of physicians in regional core hospitals, limiting the acceptance of emergency patients. Searching for available medical institutions over an extended area beyond the regular regional medical area should increase the possibility of finding medical institutions capable of accepting patients. Physician staffed helicopter ambulance system, so called the Doctor-Helicopter service is highly effective in saving patients life, since emergency doctors start to treat patients at the scene. It may be also useful to transport the critically ill patients for a long distance. A 29 year old female diagnosed twin fetus with twin-twin transfusion syndrome needs urgent delivery at about 29 weeks of gestation. The patients had to be transported to the perinatal care center which is 160 km from the hospital to where the patient was admitted because of a lack of NICU. During transportation, the maternal vital signs were stable without cervical dilatation. After arrived at the perinatal center, the patient underwent Caesarian section. Both babies had respiratory distress syndrome and admitted to NICU. With increasing cases in which medical institutions cannot accept peripartum emergency patients, it needs to search for medical institutions over an extended area and transport patients by Doctor-Helicopter.

Dilation of the ductus venosus by stent implantation increases placental blood perfusion in fetal sheep

OBJECTIVE

The reduction of resistance to flow in the ductus venous (DV) and a decrease of blood supply to the liver serve for the survival of the fetus during hypoxia. The present study investigated the influence of the increased diameter of the DV on placental blood perfusion.

STUDY DESIGN

In 15 ewes with twin pregnancies at gestational ages of 117 +/- 4 days, a stent (4 or 5 mm) was placed into the DV of 1 twin (DV(stent) group) under ultrasound guidance. Blood flow rates in the umbilical vein (UV) and DV of both fetuses were measured using Doppler ultrasound. Eight pairs of twin fetuses were included for the final analysis.

RESULTS

The dilatation of the DV increased the blood flow volume rate passed through the DV from 136.61 +/- 41.07 to 398.93 +/- 86.62 (mL/min(-1), P < .0001) and also significantly increased placental blood perfusion from 454.35 +/- 143.0 in control twin to 663.56 +/- 167.36 in the DV(stent) group (P < .05, mL/min(-1)), respectively. The DV/UV ratio increased from 30.6 +/- 11.6% in the control group to 58.9 +/- 11.6% in DV(stent) gemini (P < .0001). The positive effect of DV dilation on the placental blood perfusion was stable and could be observed up to 3 weeks after the operation.

CONCLUSION

The dilatation of the DV by means of stent implantation in the DV increased the blood flow volume rate in the umbilical vein. Fetal surviving mechanism, the increase of DV shunting rate including redistribution of the blood flow in the liver with a reduction of DV resistance to flow, could have a second effect: the improvement of reduced placental blood perfusion during hypoxia.

Comment on "Maternal oxytocin triggers a transient inhibitory switch in GABA signaling in the fetal brain during delivery"

Tyzio et al. (Reports, 15 December 2006, p. 1788) reported that maternal oxytocin triggers a transient excitatory-to-inhibitory switch of gamma-aminobutyric acid (GABA) signaling during labor, thus protecting the fetal rat brain from anoxic injury. However, a body of evidence supports the possibility that oxytocin is released from the fetal pituitary during delivery, not only from the mother, particularly under conditions of hypoxic stress.

Medical legal issues in fetal monitoring

Despite almost universal fetal monitoring during labor, debates over its role and benefits persist in the medical community and in obstetric negligence lawsuits. Irrespective, there is widespread agreement that improvement in perinatal outcome is possible and that the events of labor contribute significantly to perinatal hazards. Timely application and proper interpretation of the fetal heart rate pattern in concert with evaluations of the maternal condition and the feasibility of safe vaginal delivery permit an evaluation of the quality of care and the preventability of fetal injury whether in peer review or in malpractice cases.

Fetal cerebral oxygenation: the role of maternal hyperoxia with supplemental CO2 in sheep

OBJECTIVE

We tested the hypothesis that supplemental CO2 can enhance the effect of maternal oxygen administration on fetal cerebral oxygenation.

STUDY DESIGN

In near-term fetal sheep (n = 6), we instrumented the cerebral cortex with tissue PO2-laser Doppler flow probes, and placed arterial catheters. Following a 30-minute control period, the ewe breathed 50% O2 for 15 minutes, followed by added 6% CO2 for 15 minutes. We examined fetal cortical tissue PO2, cerebral blood flow (CBF), and fetal and maternal blood gases and related variables.

RESULTS

In response to maternal O2 administration, fetal arterial PO2, O2 content, cerebral O2 delivery, and cortical tissue PO2 increased significantly. In response to supplemental CO2 inhalation, fetal cortical tissue PO2 increased further. Fetal CBF also increased in response to the elevated arterial CO2 level.

CONCLUSION

CO2 supplementation of maternal O2 administration enhanced fetal cerebral oxygenation. In contrast, it was considered that during labor maternal hyperventilation with hypocapnia may blunt the effect of maternal O2 inhalation.

[Spontaneous pneumothorax in pregnancy. Case report]

BACKGROUND

Spontaneous pneumothorax is a rare condition during pregnancy. The most common cause is the rupture of a subpleural apical bulla or bleb, due to the increased respiratory demand of the peripartum period. The main risk for the mother is respiratory compromise; fetal risks include reduction in oxygen supply and preterm labor. The risk of recurrence is 30-40%, particularly during labor. Treatment is based on the magnitude of pneumothorax. Up to 75% of patients are treated with chest tube drainage. We present the case report of a previously healthy patient.

CASE REPORT

Our patient was a 22-year-old female at 24.2 weeks of her second pregnancy. The patient was a non-smoker, had no history of any drug addictions, and no history of previous pulmonary disease. The patient presented with sudden onset of pleuritic right-sided pleuritic chest pain associated with dyspnea. Chest examination was notable for decreased breath sounds and hyperresonance over the right hemithorax. Chest radiography showed right spontaneous pneumothorax with total lung collapse.

CONCLUSIONS

Diagnosis of pneumothorax should be considered in any pregnant woman with chest pain and dyspnea. The presented case was successfully treated with closed intercostal chest tube thoracostomy for 7 weeks.

Cesarean section on request at 39 weeks: impact on shoulder dystocia, fetal trauma, neonatal encephalopathy, and intrauterine fetal demise

PURPOSE

The purpose of this analysis was to determine the impact on specific forms of neonatal morbidity and mortality by allowing women to opt for delivery by elective cesarean section at 39 weeks of gestation (EGA). According to the National Vital Statistics Reports, over 70% of deliveries in the U.S. annually are at gestational ages>or=39 weeks EGA. Estimating that over 4 million deliveries occur annually in the United States, this would yield approximately 3 million pregnancies wherein the woman may exercise her choice for either primary or repeat cesarean section at 39 weeks EGA or at the point when labor is established.

METHODS

A search was conducted using Ovid Medline spanning the past 10 years using the following key words: fetal trauma, shoulder dystocia, brachial plexus palsy, neonatal skull fracture, obstetrical trauma, traumatic delivery, intrauterine fetal demise, stillbirth, fetal demise, and neonatal encephalopathy. Using this search technique, over 2100 articles were identified. The abstracts were reviewed and pertinent articles were chosen for further consideration. The identified articles and their applicable references were obtained for inclusion in this review. Preference was given to publications on or after the year 2000 with the exception of classical or sentinel articles, which were included without regard to year of publication.

RESULTS

Four major categories of neonatal morbidity and mortality are discussed: Shoulder dystocia: Accepting that we do not have a successful method for the prediction or prevention of shoulder dystocia, the question becomes, "What is the chance that a baby will sustain a permanent brachial plexus injury at delivery?" Additionally, is there a significant protective effect of cesarean section in reducing the risk of such injury? Currently, the occurrence rate of brachial plexus palsy at the time of vaginal delivery ranges from 0.047% to 0.6% and for cesarean section from 0.0042% to 0.095%. Using a composite estimate of the risk of 0.15% for vaginal deliveries and applying it to the 3 million deliveries>or=39 weeks EGA, approximately 4500 cases of brachial plexus palsy would occur. If only 15% of these injuries were permanent, 675 permanent brachial plexus palsies would occur annually. If the risk of permanent injury is 1 in 10,000 as reported by Chauhan, 300 permanent brachial plexus palsies would occur annually in the United States. The range then for permanent brachial plexus injury that could be avoided with cesarean section on request would appear to vary between 1 in 5000 and 1 in 10,000 vaginal births. Fetal trauma: The incidence of significant birth trauma varies from 0.2 to 1 to 2 per 1000 births. The use of sequential instruments, for example, vacuum followed by forceps or vice versa, is specifically associated with an unacceptably high injury rate. Intrapartum-related neonatal deaths of vertex singleton fetuses with birthweights>2500 g from traumatic cranial or cervical spine injury secondary to vacuum- or forceps-assisted vaginal delivery are still occurring. Overall, the frequency of significant fetal injury is significantly greater with vaginal delivery, especially operative vaginal delivery, than with cesarean section for the nonlaboring woman at 39 weeks EGA or near term when early labor has been established. Neonatal encephalopathy: The prevalence of moderate to severe neonatal encephalopathy is 3.8/1000 term live births with a neonatal fatality rate of 9.1%. In 4% to 10% of cases, the etiology appears to be pure intrapartum hypoxia. Intrapartum hypoxia superimposed on antepartum risk factors may account for up to 25% of the moderate to severe encephalopathies, according to one cohort. A paradox in the data thus far is that infants born to nonlaboring women delivered by cesarean section had an 83% reduction in the occurrence of moderate or severe encephalopathy. Considering a prevalence of moderate or severe neonatal encephalopathy of 0.38% and applying it to the 3 million deliveries occurring at >or=39 weeks EGA in the United States annually, 11,400 cases of moderate to severe encephalopathy would occur. The rate of encephalopathy observed in infants delivered by cesarean section would yield approximately 1938 cases. This net difference in moderate to severe encephalopathy would represent 9462 cases annually in the United States that could be prevented with elective cesarean section. Although cesarean delivery may be protective for the development of neonatal encephalopathy, to date it has not proven to be protective of long-term neurologic injury in the form of cerebral palsy with or without mental retardation and/or seizure disorders. Intrauterine fetal demise: Copper reported that the rate of stillbirth is consistent from 23 to 40 weeks EGA with about 5% of all stillbirths occurring at each week of gestation. Yudkin reported a rate of 0.6 stillbirths per 1000 live births from 33 to 39 weeks EGA. After 39 weeks EGA, a significant increase in the stillbirth rate was reported (1.9 per 1000 live births). Fretts reported on fetal deaths per 1000 live births from 37 to 41 weeks of gestational age, showing that the rate progressively increased from 1.3 to 4.6 with each week of gestation. It can be estimated that delivery at 39 weeks EGA would prevent 2 fetal deaths per 1000 living fetuses. This would translate into the prevention of as many as 6000 intrauterine fetal demises in the United States annually-an impact that far exceeds any other strategy implemented for stillbirth reduction thus far.

CONCLUSION

It is reasonable to inform the pregnant woman of the risk of each of the above categories, in addition to counseling her regarding the potential risks of a cesarean section for the current and any subsequent pregnancies. The clinician's role should be to provide the best evidence-based counseling possible to the pregnant woman and to respect her autonomy and decision-making capabilities when considering route of delivery.

The Current Crisis in Obstetrics

Of the issues leading to legal actions in obstetrics, the most important are events occurring before delivery that are deemed to account for the birth of a physically or mentally challenged child. In determining causation in the clinical setting, the diagnosis of fetal asphyxia can be made using blood gas and acid-base assessment. However, there are many subsidiary questions that in most cases cannot be answered, including when the asphyxia began, the severity and nature of the asphyxia during the exposure, the quality of the cardiovascular compensation, and when the brain damage occurred. When scientific proof is not available, the dilemma for the court is the requirement to reach a conclusion about the timing of brain damage on the balance of probabilities. Although it is of value, clinical risk scoring using fetal heart rate (FHR) monitoring may result in false positive predictions of fetal asphyxia. The problem in FHR monitoring is the lack of a detailed algorithm for the interpretation of FHR patterns with appropriate recommendations for management. Until such an algorithm is developed, health care workers cannot be expected to respond to fetal heart rate patterns consistently. Responsibility for the crisis in obstetrics must rest with the members of the health care disciplines who provide expert testimony. Progress made in research encourages us to assume that more is known about the causes of brain damage in the clinical setting than in fact is known. Similarly, health care professionals, parents, and lawyers often assume current methods of prediction and diagnosis to be more effective than they actually are.

Prenatal hypoxia-induced adaptation and neuroprotection that is inducible nitric oxide synthase-dependent

The incidence of perinatal stroke is approximately 0.025%. About two thirds of these patients develop long-lasting neurological deficits. Preconditioning-induced neuroprotection, a phenomenon in which application of a stimulus induces brain ischemic tolerance, is investigated to improve outcome after a perinatal stroke. We applied prenatal hypoxia to fetuses by exposing 22-day pregnant mother rats to 15% oxygen for 30 min and subjected newborns with or without this prenatal hypoxia to brain ischemia 48 h later. Newborns with the prenatal hypoxia had a lower mortality rate, less brain tissue and neuronal loss and fewer active caspase 3 (an indicator for cell apoptosis) positive brain cells than newborns with the brain ischemia only. This neuroprotection was abolished by an inhibitor of inducible nitric oxide synthase (iNOS). The expression of iNOS proteins but not endothelial and neuronal NOS proteins was increased by the prenatal hypoxia. Thus, the prenatal hypoxia-induced neuroprotection may be iNOS-dependent.

cAMP response element-binding protein activation in ligation preconditioning in neonatal brain

Perinatal hypoxic-ischemic (HI) brain injury is a major cause of permanent neurological dysfunction in children. An approach to study the treatment of neonatal HI encephalopathy that allows for neuroprotection is to investigate the states of tolerance to HI. Twenty-four-hour carotid-artery ligation preconditioning established by delaying the onset of hypoxia for 24 hours after permanent unilateral carotid ligation rats markedly diminished the cerebral injury, however, the signaling mechanisms of this carotid-artery ligation preconditioning in neonatal rats remain unknown. Ligation of the carotid artery 24 hours before hypoxia provided complete neuroprotection and produced improved performance on the Morris water maze compared with ligation performed 1 hour before hypoxia. Carotid artery ligation 6 hours before hypoxia produced intermediate benefit. The 24-hour carotid-artery ligation preconditioning was associated with a robust and sustained activation of a transcription factor, the cAMP response element-binding protein (CREB), on its phosphorylation site on Ser133. Intracerebroventricular infusions of antisense CREB oligodeoxynucleotides significantly reduced the 24-hour carotid-artery ligation-induced neuroprotection effects by decreasing CREB expressions. Pharmacological activation of the cAMP-CREB signaling with rolipram 24 hours before hypoxia protected rat pups at behavioral and pathological levels by sustained increased CREB phosphorylation. This study suggests that 24-hour carotid-artery ligation preconditioning provides important mechanisms for potential pharmacological preconditioning against neonatal HI brain injury.

Four cases of the ex utero intrapartum treatment (EXIT) procedure: anesthetic implications

The ex utero intrapartum treatment (EXIT) procedure is a method of maintaining utero-placental circulation during cesarean section to gain time to secure a potentially obstructed fetal airway. Four cases of the EXIT procedure are described with special reference to the maternal anesthetic technique. Deep volatile anesthesia (approximately 2 MAC) with isoflurane or sevoflurane for a prolonged period of time, in three cases in combination with an intravenous nitroglycerin infusion, was used to ensure a fully relaxed uterus during the procedure. All mothers were maintained hemodynamically stable with preserved utero-placentary perfusion. It was possible to intubate the tracheas of two fetuses, whereas in the other two tracheostomies had to be performed. Fetal gas exchange was not negatively affected during the EXIT procedure as evidenced by normal blood gas values in the umbilical artery at the time of delivery. After reducing the concentration of volatile anesthetic, delivery of the neonate and administration of oxytocin, uterine contractility was promptly re-established and there were no signs of uterine atony in the postoperative period. All four neonates survived the procedure without complications.

[Prevention of intrapartum fetal hypoxia by using electrocardiography]

The biophysical diagnostic methods are an unusual element of evaluation of the fetus state in the time of pregnancy and delivery. Nowadays, the applied methods of fetus supervision during labor don't ensure the permanent analysis and they don't deliver diagnostic information about fetus hypoxia. The purpose of avoiding the risk of fetus injury and its hypoxia should be developed by technologies which allow making a diagnosis of fetus condition and to detection of intralabor hypoxia, So, especially all new methods are indicated, which make easier the diagnostic in a permanent mode and which allow for hypoxia expectation and they also allow to reduce the number of unjustified medical interference. One of these methods is fetus electrocardiography.

[Aqua exercise as a prophylaxis of fetal anoxia]

The paper presents the results of the action of underwater exercises and adaptational respiratory exercise under the hypoventilation mode on health of pregnant women with threatened abortion at different terms of gestation and of their babies. The exercises led to physiological development of pregnancy, diminished intrauterine fetal hypoxia, less frequent hospitalizations of the pregnant women, good pregnancy outcomes, delivery of healthy babies. Moreover, maternal morbidity decreased 1.5-fold and perinatal morbidity 2-fold.

Is the sampling site along the umbilical artery significant?

The purpose of umbilical blood sampling is to obtain accurate reflection of fetal acid-base status at birth. The site along the umbilical artery from which blood should be sampled postpartum was not specified. We evaluated if blood gases and pH values from three sampling sites along the umbilical artery are different. After defining the range of intraobserver (method) variability, blood pO(2), pCO(2), and pH were directly determined. The data showed consistent and significant increases in arterial pH and pCO(2) values and decreases in pO(2) values from near the fetal cord insertion to the placenta. The largest difference was noted between the fetal site and the placental plate and the smallest between the site near the placental cord insertion and the placental plate. We conclude that the site of cord blood sampling should be standardized and the umbilical artery should be sampled at a site nearest to the neonate.

[Intrapartum fetal monitoring: old or new techniques?]

The objective of intrapartum fetal monitoring is to prevent fetal asphyxia and fetal death during labor. Although a large proportion of neurologic sequelae are of antepartum origin, criteria have been defined to relate cerebral palsy to an intrapartum event, including fetal asphyxia. Since the introduction of fetal heart rate monitoring, no changes in the cerebral palsy rate have been observed. Several other methods of fetal surveillance have been more or less recently developed: fetal scalp blood pH and lactates, fetal pulse oximetry and fetal electrocardiogram. The benefits and limits of these new tools are analyzed in this review.

Fetal electrocardiography in labor and neonatal outcome: data from the Swedish randomized controlled trial on intrapartum fetal monitoring

OBJECTIVE

Cardiotocography plus automatic ST analysis of the fetal electrocardiography has been shown recently to reduce both the operative delivery rate for fetal distress and the cord artery metabolic acidosis rate. The purpose of this study was to analyze findings that were related to cases with a complicated/adverse neonatal outcome in the Swedish randomized controlled trial.

STUDY DESIGN

Of the 4966 term fetuses that were included in the trial, all 351 newborn infants who required special neonatal care were identified. Cases of perinatal death, neonatal encephalopathy, or metabolic acidosis at birth were reviewed.

RESULTS

Of the 29 fetuses with adverse/complicated neonatal outcome, 22 fetuses had cardiotocography and ST patterns that indicated a need for intervention, according to the cardiotocography plus ST clinical guidelines. The number of live-born with moderate or severe neonatal encephalopathy showed a significant decrease from 0.33% (8/2447 fetuses) in the cardiotocography-only group to 0.04% (1/2519 fetuses) in the cardiotocography plus ST group.

CONCLUSION

Cardiotocography plus ST analysis provides accurate information about intrapartum hypoxia and may prevent intrapartum asphyxia and neonatal encephalopathy by giving a clear alert to the staff members who are in charge.

[New methods of monitoring the fetus during labor--detection of intrapartum fetal hypoxia by electrocardiography]

The biophysical diagnostic methods are an essential element of evaluation of the fetus state in pregnancy and delivery. Nowadays, the applied methods of fetus supervision during labour don't ensure the permanent analysis and they don't deliver diagnostic information about fetus hypoxia. With a view to avoiding the risk of fetus injury and its hypoxia technologies should be developed which allow to make a diagnosis of perils to good fetus condition and detection of intralabor hypoxia. Therefore, enhancing all new methods are indicated, which facilitate the diagnostic in a permanent mode and which allow for hypoxia prediction and the reduction of unjustified medical interferences. One of these methods is fetus electrocardiography.

The prediction and prevention of intrapartum fetal asphyxia in preterm pregnancies

OBJECTIVE

This study was undertaken to examine the contribution of electronic fetal heart rate monitoring in the prediction and prevention of intrapartum fetal asphyxia in the preterm pregnancy.

STUDY DESIGN

The outcome of 40 pregnancies with biochemically confirmed intrapartum fetal asphyxia (ie, an umbilical artery base deficit >12 mmol/L) was examined. This included 20 pregnancies that were delivered abdominally matched with 20 pregnancies that were delivered vaginally. Antepartum and intrapartum clinical risk factors and newborn complications were documented. The interpretation of the fetal heart rate record as determined by the responsible clinicians was recorded. Fetal asphyxia was classified as mild, moderate, or severe on the basis of an umbilical artery base deficit of >12 mmol/L and newborn encephalopathy and other organ system complications.

RESULTS

Fetal asphyxia was classified as mild in 21 pregnancies and as moderate or severe in 19 pregnancies. The fetal heart rate record was predictive of fetal asphyxia in 27 pregnancies and nonpredictive in 11 pregnancies. The predictive fetal heart rate record was the primary indication for intervention in 21 of the 24 pregnancies that were delivered by cesarean delivery in the first stage or operative vaginal delivery in the second stage of labor. Newborn outcome may have been influenced by intervention and delivery because of a predictive fetal heart rate record in 10 pregnancies with mild fetal asphyxia and in 9 pregnancies with moderate or severe fetal asphyxia.

CONCLUSION

Electronic fetal monitoring is a useful screening test for the prediction of intrapartum fetal asphyxia in the preterm pregnancy. A predictive fetal heart rate record was the principle indication that led to intervention and delivery. A prediction of fetal asphyxia that leads to intervention and delivery may prevent or modify moderate or severe newborn morbidity as the result of fetal asphyxia.

Hypoxic-ischemic brain injury in the newborn: pathophysiology and potential strategies for intervention

There is increasing clinical and experimental data describing the evolution of hypoxic-ischemic encephalopathy in the perinatal period. Outcome to the fetus is determined not only by the impact of gross asphyxial insult, but also external factors that sensitize the brain to injury. Delayed neuronal and glial death occurring in the hours and days after the insult by apoptotic and related processes are observed following severe injury, and offer the most promise for pharmacological intervention. Furthermore, new technologies allow the identification of subtle insults with evolving encephalopathies that have implications for long-term neurological outcome. Application of this knowledge will allow us to identify strategies for early intervention and prevent the course of damage caused by hypoxic-ischemic injury.

Hypoxic-ischemic encephalopathy

Cerebral hypoxia-ischemia (asphyxia) occurring in the fetus and newborn infant is a major cause of acute mortality and chronic neurological disability in survivors. This review highlights many practical aspects of perinatal hypoxic-ischemic brain damage, including neuropathological features, obstetrical antecedents, and clinically important aspects of identification, management, and prognosis. Diagnostic techniques, including neuro-imaging, to diagnose hypoxic-ischemic encephalopathy also are discussed. A thorough knowledge of the clinical spectrum of perinatal hypoxic-ischemic encephalopathy should enable neonatologists to undertake appropriate management strategies and prognostic indicators.

Reduced nitric oxide is involved in prenatal ischemia-induced tolerance to neonatal hypoxic-ischemic brain injury in rats

To explore the role of nitric oxide (NO) in the hypoxic-ischemic (HI) tolerance phenomenon, NO production and brain injury following neonatal hypoxia-ischemia (induced by unilateral common carotid artery ligation followed by hypoxic exposure) were assessed in rat pups with or without HI preconditioning. A previously demonstrated prenatal HI rat model of preconditioning was used in this study. On G17, rat fetuses were subjected to either HI in utero (PreHI) for 30 min or a sham operation (SH). The PreHI treatment provided significant protection against neonatal HI-induced brain injury, as indicated by decreased ipsilateral brain weight reduction, less severe tissue damage, and decreased activation of caspase-3. Concomitant with the protective effect of prenatal HI preconditioning, elevation of nitrite/nitrate content in the ipsilateral cortex of the brain, as an indirect measure of NO production, was significantly lower in the PreHI group than in the SH group following neonatal HI. The protective effect of prenatal HI preconditioning could be reversed by sodium nitroprusside (SNP), a spontaneous NO donor, while SNP had no effect on neonatal HI-induced brain injury in the SH group. Intraperitoneal administration of SNP to pups from the PreHI group (2 mg/kg, 24 and 1.5 h before neonatal HI) increased neonatal HI-induced brain injury similar to that observed in the SH group. On the other hand, L-N(G)-nitro-arginine (2 mg/kg, i.p., 1.5 h before the hypoxic exposure), an NO synthase inhibitor, significantly attenuated neonatal HI-induced brain injury in the SH group. The overall results indicate that reduced NO production in the preconditioned rat brain contributes to prenatal HI-induced tolerance to neonatal HI brain injury.

Mechanisms of perinatal brain injury

This article is focused on the mechanisms underlying primarily ischaemic/reperfusion brain injury in both the term and premature infant. Although the mechanisms involved include similar initiating events, principally ischaemia-reperfusion, and similar final common pathways to cell death, particularly free radical-mediated events, there are certain unique maturational factors influencing the type and pattern of cellular injury. We will therefore initially describe the physiological and cellular/molecular mechanisms of brain injury in the term infant, followed by the mechanisms in the premature infant.

Antenatal brain injury: aetiology and possibilities of prevention

Although the aetiology of antenatal brain injury is often unclear, procedures can be employed to prevent or reduce the risk of injury. Defective neuropore closure can be prevented by periconceptional administration of folic acid, and the incidence of other severe malformations and genetic disorders can be reduced by early identification and termination of pregnancy. Antenatal identification of IUGR, administration of corticosteroids to cases with pending preterm birth, and treatment of maternal/fetal infections would also reduce the incidence of injury. Mothers can decrease the risk of injury by maintaining a good diet, avoiding smoking, alcohol intake and exposure to TORCH infections during pregnancy.

Fetal biophysical profile

This article begins with an outline of the theoretic basis of the fetal biophysical profile, the method for the biophysical profile score (BPS), and the timing and frequency of testing. The article further discusses the clinical management based on test scores; modified methods of the BPS; and clinical application, predictive accuracy, and impact on outcome of BPS. The authors specifically examine the relationship between BPS and cerebral palsy. They conclude with a discussion of adult sequelae and fetal adaptation to asphyxia.

Intrapartum Fetal Surveillance. Is It Worthwhile?

Potentially significant intrapartum fetal asphyxia occurs in approximately 20 per 1000 births. Moderate and severe fetal asphyxia exposure with newborn morbidity occurs in 3 to 4 1000 births, with brain damage and subsequent disability in at least 1 per 1000 births. Although the prevalence of moderate and severe asphyxia is modest, prevention is important because of the serious implications of this complication to the child, family, and society. Because of the limited predictive value of clinical risk factors, the interpretation of patterns in a fetal heart rate record has become the primary screening test for intrapartum fetal asphyxia. Despite extensive clinic experience and numerous clinical trials, the benefits of EFM as a screening test have not been established, and harm may occur owing to unnecessary intervention. This observation raises serious ethical issues. When an intervention is initiated by the clinician rather than the patient, the clinician under greater obligation to ensure that the benefits outweigh the harm. Several factors complicate the demonstration of benefits of EFM as a screening test. There is no consensus regarding a protocol of fetal surveillance for low-risk patient who account for approximately 25% of intrapartum fetal asphyxia. Moderate and severe asphyxia cannot be prevented when asphyxial exposure has occurred before labor or before the onset of fetal surveillance. Prediction of intrapartum fetal asphyxia cannot occur when the quality of the record does not permit interpretation. Interpretation of predictive fetal heart rate patterns cannot occur unless the record is consistently and carefully scored. Prediction of most cases of intrapartum fetal asphyxia on the basis of fetal heart rate patterns is possible but difficult. Because the goal of intrapartum fetal surveillance is the prevention of moderate and severe fetal asphyxia, prediction must be achieved before fetal decompensation. Prediction must occur before absent baseline fetal heart rate variability evident in the record, which is uniformly associated with cerebral dysfunction and, in some cases, brain damage. The possibility of fetal asphyxia must be considered when, within a 1-hour window of recording, there are two or more cycles of minimal baseline fetal heart rate variability and two or more cycles of late or prolonged decelerations or both. Because approximately 9 of 10 predictive fetal heart rate patterns are false-positive, supplementary tests to confirm the diagnosis and to identify false-positives to prevent unnecessary intervention are essential. Until such time as additional fetal assessment tests are validated, blood gas and acid-base assessment of fetal blood can provide a definitive diagnosis and identify false-positive predictions.

Effects of vaginal birth versus caesarean section birth with general anesthesia on blood gases and brain energy metabolism in neonatal rats

Using a rat model, several laboratories have demonstrated long-term effects of Caesarean section (C-section) birth or of global hypoxia during C-section birth on a variety of central nervous system (CNS) parameters. These studies used C-section delivery from rapidly decapitated dams, to avoid confounding anesthetic effects, or from dams anesthetized with halothane or ether under unspecified conditions. Systemic oxygenation or cerebral energy metabolites in the pups at birth have not been systematically measured in this model. To develop and characterize a C-section model with relevance to the human situation, the present study measured arterial/venous blood gases and pH and brain ATP and lactate, a widely accepted measure of CNS hypoxia, in pups born either vaginally, by C-section from decapitated dams, or by C-section from dams anesthetized with nitrous oxide (N2O) and increasing concentrations of isoflurane under well-defined conditions. Immediately after birth, pups born vaginally, by C-section with maternal decapitation, or by C-section with 2.5% isoflurane showed no group differences in systemic pO2 or pH or brain ATP levels, but pCO2 was elevated in the C-section/2.5% isoflurane group. Pups born by C-section with 3.0, 3.5, or 4.0% isoflurane, showed progressive reductions in blood pO2 and increases in pCO2 and blood pH was reduced with 3.5% isoflurane. Relative to vaginal birth, brain lactate levels were unchanged in pups born by C-section with any concentration (2.5-4.0%) of isoflurane, but reduced in pups born by C-section from decapitated dams. At 1 h (and 4 h) after birth, in both vaginally born controls and the 2.5% isoflurane group, brain lactate fell while blood pO2 and brain ATP remained stable. In the 3.0, 3.5, or 4.0% isoflurane groups, blood gases and pH and brain lactate also normalized to control values. In conclusion, rat neonates show minimal signs of systemic or CNS hypoxia following C-section birth under 2.5% isoflurane with N2O. However, there is a rather narrow window of isoflurane concentrations which produces effective maternal anesthesia without producing respiratory compromise in the neonate. Thus the results indicate that the level of maternal anesthesia employed is an important factor influencing neonatal systemic and CNS oxygenation during C-section birth.

Antioxidant role of endogenous coenzyme Q against the ischemia and reperfusion-induced lipid peroxidation in fetal rat brain

BACKGROUND

Ischemia and subsequent reperfusion induce lipid peroxidation in the cerebrum of the fetal rat. The present study evaluated the antioxidant activity of endogenous coenzyme Q in protecting against the lipid peroxidation induced in the fetal rat brain by ischemia/reperfusion.

METHODS

We used wistar rats at day 19 of pregnancy. Fetal ischemia was induced by bilateral occlusion of the utero-ovarian artery for 20 minutes. For reperfusion, the occlusion was released and the circulation was restored for 30 minutes. Control rats underwent sham operation. We determined the levels of thiobarbituric acid-reactive substances, the concentrations of coenzyme Q9, coenzyme Q10, and the mitochondrial respiratory control index in fetal brains.

RESULTS

Occlusion for 20 minutes significantly reduced the respiratory control index (p < 0.01), but did not alter the levels of thiobarbituric acid-reactive substances, coenzyme Q9 or coenzyme Q10. Subsequent reperfusion, however, significantly increased the level of thiobarbituric acid-reactive substances (from 6.53+/-1.54 to 11.46+/-3.31 nM/mg of protein, p < 0.01) and significantly decreased the level of coenzyme Q9 (from 291.73+/-108.94 to 162.44+/-56.83 pM/mg of protein, p < 0.05) and that of coenzyme Q10 (from 153.10+/-75.24 to 79.84+/-30.40 pM/mg of protein, p < 0.05). The respiratory control index was still significantly lower following reperfusion than in controls (p < 0.01). Significant negative correlations were observed between the level of thiobarbituric acid-reactive substances and the concentrations of either coenzyme Q9 (r = -0.68, p < 0.001) or coenzyme Q10 (r = -0.70, p < 0.001).

CONCLUSION

Endogenous coenzyme Q may protect the fetal rat brain against the lipid peroxidation induced by ischemia/reperfusion.

[Theoretical and experimental models of sonographic diagnosis of umbilical cord knot and their application in practice]

Modern sonographic technique allows the detection of cord complication as neck cord entanglement. Far more difficult is the detection of a real cord knot. This article describes a theoretical model for detection of a cord knot and proves it in an in-vitro model.

Anesthesia for nonobstetric surgery during pregnancy

Approximately 50,000 pregnant women undergo nonobstetric surgery each year in the United States. Administering anesthesia during such surgery is one of the only situations in which anesthesia impacts on more than one individual (mother and fetus) at the same time. Providing a safe anesthetic to the pregnant woman requires an understanding of the physiologic changes of pregnancy and the impact of anesthesia and surgery on the developing fetus. The following review will consider the risks of the mother and to the fetus during nonobstetric surgery.

The Internet and randomised controlled trials

Several factors constrain the implementation of Randomised Controlled Trials (RCTs). To obtain large sample sizes a multicentred multinational trial may be necessary or a long sampling period. The larger the trial the larger is the unit cost. To allow larger sample sizes, shorter sampling periods and lower unit costs, new methods are needed. The Internet and in particular the WWW provides such an opportunity. The WWW can provide global access, fast interaction and automation. A prototype Internet Trials Service (ITS) is currently being tested with a real international clinical trial (the Growth Restriction Intervention Trial--GRIT). The ITS is hosted on a Web server. It provides a series of HTML documents that describe the GRIT protocol. Registered centres may enter patients into the GRIT trial via ITS. Java applets are used to collect trial data before returning the study number and randomisation. ITS assumes all trial data will be intercepted by a sniffer. Therefore no information is sent that could specifically identify a patient, this must be sent later by more secure means. ITS assumes that trial centres can be spoofed. To authenticate the patients entered into the trial and the trial data sent, a regular audit report is sent to each centre by secure means for confirmation. By using Java, a full functional data entry system can be developed that runs locally within any Java enabled browser. It can perform data validation locally and also provide a sophisticated user interface.

Cerebral hemodynamics and oxygenation in the fetus. The role of intrapartum near-infrared spectroscopy

Current methods of intrapartum surveillance have made little impact on fetal mortality and morbidity while leading to increased caesarean section rates. Near-infrared spectroscopy is a powerful new technique that can continuously measure changes in fetal cerebral oxygenation and hemodynamics during labor. Data are presented suggest that near-infrared spectroscopy has potential as a new form of fetal monitoring. However, further technical developments and testing in clinical trials are necessary before its introduction into clinical practice.

[Fetal plasma erythropoietin concentration during intrauterine transfusion therapy in isoimmunohemolytic anemia due to rhesus incompatibility]

PURPOSE

Prenatal plasma concentrations of erythropoietin in fetuses with Rh disease should contribute information to the clinical course and therapeutic control of this disease.

METHOD

Fetal plasma erythropoietin (Epo) and haemoglobin (Hb) concentrations were measured in 145 umbilical venous blood samples of 30 fetuses with Rh disease at 20 to 38 weeks' gestation.

RESULTS

Both Epo and Hb concentrations were independent of the gestational age in red blood cell-isoimmunised pregnancies. The Hb concentration correlated significantly with Epo concentration without intrauterine transfusion (IUT) (r = -0.519, p = 0.005) and after IUT (i = -0.212, p = 0.01). A haemoglobin deficit of 3 g/dl at 20 weeks' gestation increased to 6 g/dl at 38 weeks' gestation in spite of IUT (p = -0.354, p < 0.001).

CONCLUSION

Even with IUT, Epo concentrations increase with gestational age during these pregnancies. This is due to increasing Hb deficits indicating fetal hypoxia which might be prevented by increasing volumes of transfusion.