Systematic Review of Intrapartum Fetal Heart Rate Spectral Analysis and an Application in the Detection of Fetal Acidemia

It is fundamental to diagnose fetal acidemia as early as possible, allowing adequate obstetrical interventions to prevent brain damage or perinatal death. The visual analysis of cardiotocography traces has been complemented by computerized methods in order to overcome some of its limitations in the screening of fetal hypoxia/acidemia. Spectral analysis has been proposed by several studies exploring fetal heart rate recordings while referring to a great variety of frequency bands for integrating the power spectrum. In this paper, the main goal was to systematically review the spectral bands reported in intrapartum fetal heart rate studies and to evaluate their performance in detecting fetal acidemia/hypoxia. A total of 176 articles were reviewed, from MEDLINE, and 26 were included for the extraction of frequency bands and other relevant methodological information. An open-access fetal heart rate database was used, with recordings of the last half an hour of labor of 246 fetuses. Four different umbilical artery pH cutoffs were considered for fetuses' classification into acidemic or non-acidemic: 7.05, 7.10, 7.15, and 7.20. The area under the receiver operating characteristic curve (AUROC) was used to quantify the frequency bands' ability to distinguish acidemic fetuses. Bands referring to low frequencies, mainly associated with neural sympathetic activity, were the best at detecting acidemic fetuses, with the more severe definition (pH ≤ 7.05) attaining the highest values for the AUROC. This study shows that the power spectrum analysis of the fetal heart rate is a simple and powerful tool that may become an adjunctive method to CTG, helping healthcare professionals to accurately identify fetuses at risk of intrapartum hypoxia and to implement timely obstetrical interventions to reduce the incidence of related adverse perinatal outcomes.

Postpartum infection in relation to maternal characteristics, obstetric interventions and complications

The purpose was to evaluate the association between maternal characteristics, obstetrical interventions/complications and postpartum wound infections (WI), urinary tract infection (UTI) and endometritis. Furthermore, this study aimed to determine the time from delivery to onset of infections after discharge from the hospital. Three large Swedish Medical Health Registers were scrutinized for the period 2005–2012. A total of 582,576 women had 795,072 deliveries. Women with diagnosis codes for WIs, UTIs or endometritis, from delivery to 8 weeks postpartum, were compared to non-infected women. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated. Increasing age and body mass index (BMI) were both associated with increasing prevalence of postpartum infections. WIs were most strongly associated with cesarean section (CS) (OR 17.2; 95%CI 16.1–18.3), 3rd and 4th degree tears (OR 10.7%; 95%CI 9.80–11.9) and episiotomy (OR 10.2; 95%CI 8.94–11.5). Endometritis was associated with anemia (OR 3.16; 95%CI 3.01–3.31) and manual placental removal (OR 2.72; 95%CI 2.51–2.95). UTI was associated with emergency CS (OR 3.46; 95%CI 3.07–3.89) and instrumental delivery (OR 3.70; 95%CI 3.29–4.16). For women discharged from the delivery hospital the peak occurrence of UTI was 6 days postpartum, while for WIs and endometritis it was 7 days postpartum.

Factors influencing colostrum yield by sows

ABSTRACT An adequate colostrum intake, in order to ensure the survival and weight gain of piglets, depends on the sow's ability to produce enough colostrum for the whole litter. The aim of this study was to evaluate factors involved in colostrum yield (CY) variability related to the sow, the litter and the farrowing process. The experiment was conducted with 96 Camborough 25(r) sows of parities one to seven, whose farrowing was spontaneous. Colostrum production of each sow was estimated by summing up the colostrum intake of each piglet in the litter, estimated by an equation that takes into account the birth weight and weight gain during the first 24h of life. The multiple regression model explained 28% of variation in CY, with 24% and 4% respectively of variation being explained by the litter birth weight and the width of the first mammary glands. Litter birth weight was positively correlated with the number of total born (r= 0.73) and born alive piglets (r= 0.83). When categorised into two groups of colostrum yield (LOWCY; ≤3.4kg; n= 46 vs HIGHCY; >3.4kg; n= 50), LOWCY sows had fewer total born and born alive piglets and lighter litters (P<0.05). The logistic regression analysis showed that sows from parities 1, 2 and >3 had greater odds (P≤0.05) of belonging to the LOWCY group than parity 3 sows. Sows with two or more obstetrical interventions had higher odds (P<0.05) of belonging to the LOWCY group than sows without interventions during farrowing. The higher colostrum yield observed in sows of parity 3 and sows with less than two obstetrical interventions during farrowing was associated with a greater number of nursed piglets. This study showed that total birth weight of born alive piglets is the most important factor involved in colostrum yield variability, indirectly representing the number of piglets nursed by the sow.