Electrohysterography for uterotonic efficiency estimation

Uvod: Poporodna krvavitev je vodilni vzrok maternalne obolevnosti in umrljivosti v svetu. Najpogostejši vzrok za njen pojav (do 90 % primerov) je atonija ali neprimerno krčenje maternice. Karbetocin je agonist oksitocinskih receptorjev, ki je po zadnjih raziskavah enakovreden, oziroma še bolj učinkovit od priporočenega uterotonika oksitocina. Elektrohisterografija je objektivna, neinvazivna metoda spremljanja dinamike delovanja maternice, ki so jo v raziskovalne namene že obsežno uporabili v nosečnosti, med porodom. Zaenkrat še ni znane raziskave, kjer bi s pomočjo elektrohisterografije preverjali učinkovitost uterotonikov na krčljivost maternice po porodu. Namen naše raziskave je bil primerjati spremembe v poporodnem elektrohisterogramu pri porodnicah, ki so po carskem rezu prejele preventivni odmerek oksitocina ali karbetocina. Metode: V enocentrično randomizirano raziskavo smo vključili 64 zdravih nosečnic z enoplodno nosečnostjo ob roku (? 37 tednov nosečnosti), predvidenih za elektivni carski rez, zaradi stanja po predhodnem carskem rezu. Po operaciji smo porodnicam odvzeli vzorec krvi za laboratorijske preiskave (hemogram) in posneli 15-minutni elektrohisterogram. Preiskovanke smo randomizirali v dve skupini: prva skupina je prejela enkratni odmerek karbetocina 100 µg (Pabal®) intravensko, druga skupina je prejela 5 IE oksitocina (Syntocinon®) intravensko. Po prejetem uterotoniku smo posneli 30-minutni elektrohisterogram, ki mu je sledil še tretji 30-minutni EHG dve uri po aplikaciji zdravila. Ob vsakem snemanju elektrohisterograma smo pacientke prosili, da ovrednotijo bolečino s pomočjo vizualno analogne skale. Elektrohisterograme smo snemali s pomočjo dveh parov bipolarnih elektrod na trebušni steni, uporabili smo za to namenjen snemalni aparat. Na elektrohisterogramu smo vizualno identificirali salvam podobne kontraktilne elemente (»psevdo salve«). Preko Fourierove analize smo za vsak analiziran kontraktilni element pridobili integral spektra gostote moči. Analizirali smo tudi srednjo vrednost najvišje frekvence, srednjo vrednost najvišje amplitude spektra gostote moči, pogostost in trajanje psevdo salv. Rezultati: Sprememba (med sprejemom in po dveh urah po uterotoniku) najvišje frekvence spektra gostote moči je bila statistično pomembno manjša v oksitocinski skupini (Mediana spremembe= 0,07 Hz (Interkvartilni razpon: 0,87 Hz) v primerjavi s karbetocinsko skupino (Mediana spremembe = – 0,63 Hz (Interkvartilni razpon: 0.20 Hz)p = 0,004, Wilcoxonov test predznačenih rangov). Statistično pomembno razliko smo beležili pri najvišji frekvenci spektra gostote moči dve uri po aplikaciji uterotonika, kjer smo namerili povišanje v oksitocinski skupini in znižanje v karbetocinski skupini (Mediana = 0,43 Hz (Interkvartilni razpon: 0,12 Hz) v primerjavi z Mediano = 0,39 Hz (Interkvartilni razpon: 0,08 Hz)p = 0,030, Mann-Whitneyev U test). Pri ostalih parametrih nismo beležili statistično značilnih razlik. Statistično značilne razlike v spremembi v hemoglobinu in hematokritu v 24 urah po carskem rezu nismo dokazali. Ugotovili nismo niti statistično značilnih razlik v oceni bolečine s pomočjo vizualno analogne skale med obema skupinama preiskovank, beležili smo primerljive neželene učinke. Zaključek: Izmerili smo pomembno višji elektrohisterografski parameter, najvišjo frekvenco spektra gostote moči, dve uri po aplikaciji oksitocina v primerjavi s skupino, ki je prejela karbetocin. Elektrohisterografija po porodu lahko predstavlja dodatno, objektivno metodo za preučevanje učinkovitosti uterotonikov.Introduction: Postpartum haemorrhage is the leading cause of worldwide maternal morbidity and mortality. The most frequent cause for its occurrence (90 % of cases) is uterine atony or disfunctional uterine contraction. Carbetocin is an oxytocin receptor agonist, latest studies have shown its noninferiority, some even superiority in efficiency compared to the recommended uterotonic oxytocin. Electrohysterography is an objective, noninvasive method for monitoring uterine activity dinamics, it was extensively used in research of pregnancy and labour. Until now there is no known study estimating uterotonic efficiency on the postpartal contracting uterus using electrohysterography. The aim of our study was to compare changes in postpartum electrohysterogram in women after caesarean section after preventive uterotonic application, either oxytocin or carbetocin. Methods: In our single center randomised study 64 healthy women with singleton pregnancy at term (⡥ 37 weeks of gestation) scheduled for caesarean section after a previous caesarean section were included. After the procedure, a blood sample was obtained for laboratory analysis (haemogram) and a 15-minute electrohysterogram was recorded. Women were randomised in two groups: the first received a single dose of 100 μg of carbetocin (Pabal®) intravenously, the second received 5 IU of oxytocin (Syntocinon®) intravenously. After uterotonic application a 30-minute electrohysterogram was obtained, followed by a third electrohysterogram two hours after therapy administration. While recording each electrohysterogram, we asked women to assess their pain using a visual analogue scale. Electrohysterograms were obtained using two pairs of bipolar electrodes placed on the abdominal wall, with a custom-made recording machine. On the electrohysterograms we visually identified burst like contractile elements (»pseudo bursts«). Each contractile element was analysed via Fourier transformation and a power density spectrum integral was obtained. We analysed the mean value of power density spectrum peak frequency, the mean value of power density spectrum peak amplitude, the frequency and duration of pseudo bursts. Results: The change in power density spectrum peak frequency (from admission to two hours after uterotonic application) was statistically significantly lower in the oxytocin group compared to carbetocin (Median of change = 0,07 Hz (Interquartile range: 0,87 Hz) compared to Median of change = – 0,63 Hz (Interquartile range: 0.20 Hz)p = 0,004, Wilcoxon signed-rank test). A statistically significant difference was seen in power density spectrum peak frequency two hours after uterotonic, an increase was recorded in the oxytocin and a decrease in the carbetocin group (Median = 0,43 Hz (Interquartile range: 0,12 Hz) compared to Median = 0,39 Hz (Interquartile range: 0,08 Hz)p = 0,030, Mann-Whitney U test). No statistically significant differences were observed in other parameters. A statistically significant difference in change of haemoglobin and haematocrit 24 hours after caesarean section was not obtained. There were no statystically significant differences in assessment of pain using the visual analogue scale between the two groups, while similar unwanted effects were noted. Conclusions: We found a significantly higher electrohysterographic parameter power density spectrum peak frequency two hours after oxytocin, compared to carbetocin application. Postpartal electrohysterography could represent an additional objective tool for uterotonic efficiency estimation

Pregnancy loss after amniocentesis and chorionic villus sampling: Cohort study

Introduction: To estimate the procedure-related risks of pregnancy loss following chorionic villus sampling (CVS) and amniocentesis (AC) compared to pregnancies without procedure

Comparison of Oxytocin vs. Carbetocin Uterotonic Activity after Caesarean Delivery Assessed by Electrohysterography: A Randomised Trial

Electrohysterography has been used for monitoring uterine contractility in pregnancy and labour. Effective uterine contractility is crucial for preventing postpartum haemorrhage. The objective of our study was to compare postpartum electrohysterograms in women receiving oxytocin vs. carbetocin for postpartum haemorrhage prevention after caesarean delivery. The trial is registered at ClinicalTrials.gov with the identifier NCT04201665. We included 64 healthy women with uncomplicated singleton pregnancies at term scheduled for caesarean section after one previous caesarean section. After surgery, a 15 min electrohysterogram was obtained after which women were randomised to receive either five IU of oxytocin intravenously or 100 μg of carbetocin intramuscularly. A 30 min electrohysterogram was performed two hours after drug application. Changes in power density spectrum peak frequency of electrohysterogram pseudo-bursts were analysed. A significant reduction in power density spectrum peak frequency in the first two hours was observed after carbetocin but not after oxytocin (median = 0.07 (interquartile range (IQR): 0.87 Hz) compared to median = −0.63 (IQR: 0.20) Hz; p = 0.004). Electrohysterography can be used for objective comparison of uterotonic effects. We found significantly higher power density spectrum peak frequency two hours after oxytocin compared to carbetocin