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© 2018 Elsevier Ltd A caesarean section (CS) can be a life-saving intervention when medically indicated, but this procedure can also lead to short-term and long-term health effects for women and children. Given the increasing use of CS, particularly without medical indication, an increased understanding of its health effects on women and children has become crucial, which we discuss in this Series paper. The prevalence of maternal mortality and maternal morbidity is higher after CS than after vaginal birth. CS is associated with an increased risk of uterine rupture, abnormal placentation, ectopic pregnancy, stillbirth, and preterm birth, and these risks increase in a dose–response manner. There is emerging evidence that babies born by CS have different hormonal, physical, bacterial, and medical exposures, and that these exposures can subtly alter neonatal physiology. Short-term risks of CS include altered immune development, an increased likelihood of allergy, atopy, and asthma, and reduced intestinal gut microbiome diversity. The persistence of these risks into later life is less well investigated, although an association between CS use and greater incidence of late childhood obesity and asthma are frequently reported. There are few studies that focus on the effects of CS on cognitive and educational outcomes. Understanding potential mechanisms that link CS with childhood outcomes, such as the role of the developing neonatal microbiome, has potential to inform novel strategies and research for optimising CS use and promote optimal physiological processes and development.

Objectives To explore if in early fetal growth restriction (FGR) the longitudinal pattern of short-term fetal heart rate (FHR) variation (STV) can be used for identifying imminent fetal distress and if abnormalities of FHR registration associate with two-year infant outcome. Methods The original TRUFFLE study assessed if in early FGR the use of ductus venosus Doppler pulsatility index (DVPI), in combination with a safety-net of very low STV and / or recurrent decelerations, could improve two-year infant survival without neurological impairment in comparison to computerised cardiotocography (cCTG) with STV calculation only. For this secondary analysis we selected women, who delivered before 32 weeks, and who had consecutive STV data for more than 3 days before delivery, and known infant two-year outcome data. Women who received corticosteroids within 3 days of delivery were excluded. Individual regression line algorithms of all STV values except the last one were calculated. Life table analysis and Cox regression analysis were used to calculate the day by day risk for a low STV or very low STV and / or FHR decelerations (DVPI group safety-net) and to assess which parameters were associated to this risk. Furthermore, it was assessed if STV pattern, lowest STV value or recurrent FHR decelerations were associated with two-year infant outcome. Results One hundred and fourty-nine women matched the inclusion criteria. Using the individual STV regression lines prediction of a last STV below the cCTG-group cut-off had a sensitivity of 0.42 and specificity of 0.91. For each day after inclusion the median risk for a low STV(cCTG criteria) was 4% (Interquartile range (IQR) 2% to 7%) and for a very low STV and / or recurrent decelerations (DVPI safety-net criteria) 5% (IQR 4 to 7%). Measures of STV pattern, fetal Doppler (arterial or venous), birthweight MoM or gestational age did not improve daily risk prediction usefully. There was no association of STV regression coefficients, a last low STV or /and recurrent decelerations with short or long term infant outcomes. Conclusion The TRUFFLE study showed that a strategy of DVPI monitoring with a safety-net delivery indication of very low STV and / or recurrent decelerations could increase infant survival without neurological impairment at two years. This post-hoc analysis demonstrates that in early FGR the day by day risk of an abnormal cCTG as defined by the DVPI protocol safety-net criteria is 5%, and that prediction of this is not possible. This supports the rationale for cCTG monitoring more often than daily in these high-risk fetuses. Low STV and/or recurrent decelerations were not associated with adverse infant outcome and it appears safe to delay intervention until such abnormalities occur, as long as DVPI is in the normal range.

Objectives. The aim was to study the physiological effects of induced ventricular fibrillation and subsequent circulatory arrest for defibrillation threshold testing on the brain using the EEG, jugular bulb oxymetry and near-infrared spectroscopy. Methods. Thirteen patients undergoing surgery for implantable cardioverter-defibrillator implantation or replacement under general anesthesia were included. We continuously monitored the jugular bulb oxygen saturation (SjO2), regional oxygen saturation (rSO2) and the EEG. Results. 59 episodes of circulatory arrest were studied. In all cases the rSO2 fell instantly while the EEG changed within 12 ± 4 seconds after induction. The EEG indicated ischemic changes, ranging from occurrence of rhythmic delta activity to cessation of all electrical activity. On successful defibrillation the rSO2 increased to values in excess of pre-arrest levels and restored towards baseline; the SjO2 initially fell followed by a similar overshoot. Recovery times increased in proportion to arrest duration. Conclusion. Short lasting episodes of circulatory arrest have serious, but transient effects on brain function. The rSO2 is an effective non-invasive tool for monitoring cerebral oxygenation during DFT-testing.

Ultrasound-guided near-nerve neurography is a new tool that can be used to assess nerve regeneration before reinnervation occurs. In this study, ultrasound-guided near-nerve measurements were validated against axon diameter counts in rabbits during a 15-week regeneration period after a crush lesion of their peroneal nerve. The course of the nerve was determined ultrasonically, and the active near-nerve needle electrode was maneuvered just next to the nerve under ultrasound guidance. Measured action potentials were compared with axon diameter counts from histological sections of these same nerves. A moderate to good positive correlation was found, which reached a maximum of 0.7 at a cut-off of 3 mu m, corresponding to the minimal size of the myelinated axons. Our results suggest that, following a similar validation study in humans, ultrasound-guided near-nerve neurography may be clinically useful when early evaluation of nerve activity is needed. Muscle Nerve

The trade-off between brood size and offspring quality as predicted by life history theory, has been extensively studied in birds. However, in sexually size-dimorphic birds, where the larger sex requires more investment from the parents, the potential additional trade-off between brood sex ratio and offspring quality has received less attention. Effects of brood sex composition on nestling fitness can have implications for optimal sex allocation strategies. A harmful effect of a higher proportion of the larger sex on either one of the sexes predicts selection towards parents producing the less harmful, smaller sex. In addition to Fisherian equal allocation this should lead to considerable sex ratio biases in extremely sexually size-dimorphic birds. We tested this in the Eurasian Sparrowhawk Accipiter nisus, where female nestlings require about 40% more parental investment than male nestlings. Sex-specific nestling body mass, calculated as the relative difference with the average body mass, corrected for age, for both sexes, was used as an indicator of nestling quality. With a sample size of 120 broods, containing 483 nestlings, we found that individual nestlings were of lower body mass when they hatched in larger and female dominated broods. This effect was particularly pronounced in female nestlings. Under these conditions, sex ratio theory predicts a male bias in the population. However, this is not supported by empirical evidence from literature.

The N-15-isotope dilution technique (N-15-IDT), with either pulse-dose oral administration or continuous i.v. administration of [N-15]-L-leucine (carotid artery), both at 5 mg/(kg body weight . d), was used to measure ileal (postvalve T-cecum cannula) endogenous nitrogen recovery (ENR) in pigs (9 +/- 0.6 kg). Diets were cornstarch, enzyme-hydrolyzed casein with no (control) or high (4%) content of quebracho extract (Schinopsis spp.) rich in condensed tannins. Blood was sampled from a catheter in the external jugular vein. Mean plasma N-15-enrichment at d 8-10 was higher (P = 0.0009) after i.v. than after oral administration [0.0356 vs. 0.0379 atom% excess (APE)]. Plasma 15N-enrichment for i.v. infused pigs was 0.01117 APE higher (P

The EEG was monitored in 56 patients during implantation of an internal cardioverter defibrillator. The purpose of this study was to determine the main EEG frequency ranges that represent ischemic changes during short periods of circulatory arrest. The EEG was recorded with a 16-channel common reference montage (Cz). After onset of circulatory arrest, the log spectral changes of three-epoch moving averages were calculated relative to the baseline spectrum. For factor analysis, 17 EEG periods were selected that showed changes progressing to an isoelectrical period. Topographic differences and the time course of quantitative EEG (qEEG) changes were studied in all 56 patients. For each patient the EEG period with the longest duration of circulatory arrest was chosen. Factor analysis revealed four factors that represented the spectral EEG changes occurring during circulatory arrest and recovery. The frequency intervals of these factors were 0 to 0.5 Hz, 1.5 to 3 Hz, 7.5 to 9.5 Hz, and 15 to 20 Hz for all channels. Only minor topographic differences were found in the power of the spectral changes; the sequence of events was similar for all electrode positions. The first EEG change after circulatory arrest was an initial increase in alpha power and a decrease in beta power. On average, after approximately 15 seconds alpha power started to decrease, beta power decreased further, delta-1 power started to increase, and delta-2 power started to decrease. After approximately 25 seconds, the delta-1 power increase appeared to plateau or to decrease. A circulatory arrest longer than approximately 30 seconds resulted in an isoelectrical EEG. After restoration of the circulation, there was a fast transient increase in delta-1 and delta-2 power, followed by a decrease to baseline. alpha and beta power showed a more gradual increase in power toward baseline and were the last to restore after 60 to 90 seconds. In general, the spectral changes in the alpha and beta frequency ranges were most pronounced and consistent. In conclusion, to detect intraoperative cerebral ischemia, monitoring of changes in the four frequency ranges found is preferable to monitoring changes in the classically defined frequency bands. Furthermore, these results stress the importance of the alpha and beta ranges in detecting cerebral ischemia.

This study was designed to gain insight into the influence of spraying and cooling, during artificial incubation, on the embryo metabolic rate and hatching ability of Muscovy duck eggs. Three times a week 93 incubated eggs were sprayed and cooled for 0.5 h at room temperature. Daily embryo metabolic rate was measured in 30 eggs with a water vapor conductance ranging from 1.15 to 2.07 mg/day.kPa. Egg weight ranged from 63.73 to 84.52 g; length and breadth ranged from 59.6 to 66.4 mm and 43.2 to 48.2 mm, respectively. According to observed hatching ability, eggs were classified by three categories: eggs that hatched normally; eggs that were assisted during hatching, and nonhatched eggs. Five ducklings were assisted during hatching. Four ducklings died on Day 31, two on Day 32, and two on Day 34. Two functions were derived by discriminant analysis and accounted for 100% of the variation among the three categories of hatching ability. Collectively, these functions were able to classify 93.3% of the eggs in the correct hatching category. Egg length and metabolic rate at Days 21 and 28 of incubation were the most important predictor variables of the two functions. The results obtained in the present study indicate that an incubation temperature of 37.5 C with spraying and cooling seems to be beneficial for larger eggs.

We dissected carcasses of neonates belonging to ducks and geese (Anatidae; 8 species), shorebirds (Charadriidae and Scolopacidae; 12 species), gulls and terns (Laridae; 3 species), and nonanseriform water birds (Podicipedidae and Rallidae; 2 species) ranging in yolk-free lean wet body mass from 2.5 to 70 g. We have fitted allometric relationships between the lean wet mass of each component and the lean wet yolk-free neonatal body mass. The exponents of the relationships of the brain mass (0.73) or head mass (0.85) to neonatal body mass were significantly lower than 1. The exponents did not differ significantly from 1 for the heart, whole leg, leg bone, liver, intestines, pectoral muscles, skin, stomach, wings, feathers, yolk (wet and dry), and remainder of the body. The exponent for leg muscle mass (1.18) was significantly higher than 1. This suggests that larger chicks may have a higher potential for thermogenic heat production. At a given body mass, no differences could be detected with respect to the lean fresh leg muscle mass among ducklings, shorebirds, and the nonanseriform water birds. However, the high fractional lipid-free dry lean matter content of the leg muscles of ducklings (which might represent a high amount of contractile proteins in these muscles) could explain their observed high thermogenic heat production in response to cold stress. The exponents of feather mass and lean wet skin mass to body mass were significantly higher than 0.67 (i.e. surface-to-volume relationship of a sphere), in accordance with our previous finding that large neonates have a relatively lower minimal thermal conductance per unit surface area than smaller chicks.