Lesiones del suelo pélvico tras parto vaginal con forceps evaluadas mediante ecografía 3/4d transperineal

Objetivos: Determinar una tasa precisa de avulsión del músculo elevador del ano (MEA) asociada al uso de fórceps, teniendo en cuenta las características de la instrumentación, evaluada por ecografía translabial tridimensional. Material y métodos: Se realiza un estudio observacional prospectivo en el periodo de tiempo comprendido entre septiembre 2016 y marzo 2017. Tras el parto, todas las primíparas con un parto vaginal eutócico o un parto instrumentado con fórceps fueron invitadas a participar en el estudio, reclutando a un total de 183 pacientes, de las cuales 176 completaron el estudio (89 en el grupo de ‘fórceps’ y 87 en el grupo de ‘eutócicos’ (96.2%). Se recogieron parámetros obstétricos generales, así como las características de instrumentación: altura de la presentación (‘medio’: III plano, ‘bajo’: IV plano de Hodge), posición (occipito-anterior, occipito-posterior, transversa), presencia de asinclitismo y si se realizó desarticulación y retirada de las ramas antes del nacimiento. Entre los 6 y 12 meses postparto se realizó una evaluación del músculo elevador del ano mediante ecografía transperineal 3-4 dimensiones (3-4D) que incluyó la captura de 6 volúmenes por paciente: 2 en reposo, 2 en Valsalva y 2 con contracción máxima. La avulsión del músculo elevador del ano se estableció utilizando el modo ‘Multiview’ (obtenido a partir del plano de mínimas dimensiones), en aquellos casos en los que se apreció discontinuidad entre las fibras del músculo puborrectal y la rama púbica inferior en los 3 cortes centrales. El microtrauma se definió como un aumento ≥ 20% en el área del hiato al Valsalva. Resultados: Se identificó una avulsión del músculo elevador del ano en 46 mujeres (26%), con 12 casos (13,8%) pertenecientes al grupo de pacientes ‘eutócicos’ y 34 (38,2%) al grupo de ‘fórceps’ (p = 0,005, OR cruda 4 (1,5-10,4) y multivariante del OR ajustada 5.46 (1.91- 15.61)). No se objetivó una diferencia significativa en la tasa de microtrauma entre grupos de estudio. Conclusiones: El uso del fórceps de forma estandarizada es un factor de riesgo para la avulsión del músculo elevador del ano

Intra and interobserver variability of intrapartum transperineal ultrasound measurements with contraction and pushing

The aim of this study was to evaluate the inter- and intraobserver correlation of the different intrapartum-transperineal-ultrasound-parameters(ITU) (angle of progression (AoP), progression-distance (PD), head-direction (HD), midline-angle (MLA) and head-perineum distance (HPD)) with contraction and pushing. We evaluated 28 nulliparous women at full dilatation under epidural analgesia. We performed a transperineal ultrasound evaluating AoP and PD in the longitudinal plane, and MLA and HPD in the transverse plane. Interclass correlation coefficients (ICC) with 95% CIs and Bland–Altman analysis were used to assess intra- and interobserver measurement’s repeatability. The ICC of the ITU for the same observer was adequate for all the parameters (p < .005) AoP 0.98 (95%CI, 0.96–0.99), PD 0.98 (95%CI, 0.97–0.99), MLA 0.99 (95%CI, 0.97–0.99), HPD 0.96 (95%CI, 0.88–0.99). The ICC of the ITU for interobserver was: AoP 0.93 (95%CI, 0.79–0.98), PD 0.92 (95%CI, 0.76–0.97), MLA 0.77 (95%CI, 0.42–0.92), HPD 0.47 (95%CI, −0.12–0.8). The HD had an interobserver correlation of 0.53 (95%CI, 0.1–0.9) (Kappa C). The mean difference of the AoP was 2.42°, of the PD 1 mm and 0.28° MLA (Bland–Altman test). ITU has an adequate intra- and interobserver correlation for its use with contraction and pushing under epidural analgesia.Impact statement What is already known on this subject: The intrapartum transperineal ultrasound parameters can be used with contraction and pushing under epidural analgesia. What the results of this study add to what we know: ITU may be used to evaluate the difficulty of instrumental delivery/to evaluate the difficulty of instrumentation in vaginal operative deliveries and this study concludes that ITU is reproducible during uterine contraction with pushing. What the implications are of these findings for clinical practice and/or further research: Therefore, ITU could be used without difficulty with an adequate intra- and interobserver correlation for the prediction of instrumentation difficulty in operative vaginal deliveries

A comparable rate of levator ani muscle injury in operative vaginal delivery (forceps and vacuum) according to the characteristics of the instrumentation.

Forceps delivery is associated with a high rate of levator ani muscle (LAM) trauma (avulsion) at 35%-65% whereas data on avulsion rates after vacuum delivery vary greatly. Nevertheless, a common characteristic of all previous studies carried out to evaluate the association between instrumental deliveries (forceps and vacuum) and LAM avulsion, is the fact that characteristics of the instrumentation have not been described or evaluated. The objective of this study is to compare the rate of LAM avulsion between forceps and vacuum deliveries according to the characteristics of the instrumentation. Prospective, observational study, including 263 nulliparous women, who underwent an instrumental delivery with either Malmström vacuum or Kielland forceps. The characteristics of the instrumentation, position (anterior position and other position) and height of the fetal head at the moment of instrumentation (low instrumentation [vertex at +2 station] and mid-instrumentation [head is involved but leading part above +2 station]) were assessed. Evaluation of LAM avulsion was performed at 6 months postpartum by three-/four-dimensional transperineal ultrasound. Using the multi-view mode, a complete avulsion was diagnosed when the abnormal muscle insertion was identified in all three central slices, that is, in the plane of minimal hiatal dimensions and the 2.5-mm and 5.0-mm slices cranial to this one. To detect a 30% or 15% difference in the LAM injury rate, with 80% power and 5% α-error, we needed, respectively 42 and 99 women per study group. In all, 263 nulliparous individuals have been evaluated (162 vacuum deliveries, 101 forceps deliveries). Instrumentation in an occipito-anterior position was more frequent in vacuum deliveries (75.3% vs 56.4%, P = .002), whereas other positions were more frequent in the forceps deliveries group (24.7% vs 43.6%). No statistically significant differences were noted regarding the height of the fetal head at the moment of instrumentation. No statistically significant differences were found in the presence of LAM avulsion (41.4% vs 38.6%) between vacuum and forceps deliveries. The univariate analysis of the crude odds ratio was 1.17, 95% CI 0.67-1.98, P = .70 for the avulsion of the LAM and the multivariate of the adjusted OR 0.90, 95% CI; 0.53-1.55, P = .71. We consider that, in our population, LAM avulsion rate should not be a factor taken into account when choosing the type of instrumentation (Malmström vacuum or Kielland forceps) in an operative delivery

A prospective observational study on the influence of the difficulty of forceps application and the avulsion of the levator ani muscle

Background: To compare the rate of levator ani muscle (LAM) avulsion between normal deliveries (ND) and forceps deliveries (FD) and to determine whether the difficulty of forceps application in FD is related to the occurrence of LAM avulsion. Methods: This prospective observational study included 240 primiparous patients (125 ND and 115 FD). FD were classified according to the difficulty of forceps application. The application was considered difficult if the fetal head was in a transverse position or if it was midforceps (head engaged by the leading part was above +2 stations) with the fetal head in the occipito-posterior position; otherwise, the application was considered easy. Ultrasound evaluation was performed 6 months after delivery, and complete avulsion was diagnosed when there was abnormal insertion of the LAM in all three central slices. Results: There were statistically significant differences between the ND and FD groups in the presence of LAM avulsion (15.6% vs. 38.3%;

Intrapartum transperineal ultrasound used to predict cases of complicated operative (vacuum and forceps) deliveries in nulliparous women

IntroductionThe objective of this study was to investigate the predictive value of intrapartum transperineal ultrasound in the identification of complicated operative (vacuum or forceps) deliveries in nulliparous women.Material and methodsProspective observational study of nulliparous women with an indication for operative delivery who underwent intrapartum transperineal ultrasound before fetal extraction. Managing obstetricians were blinded to the ultrasound data. Intrapartum transperineal ultrasound was performed immediately before blade application, both at rest and concurrently with contractions and active pushing. Operative delivery was classified as complicated when one or more of the following situations occurred: three or more tractions; a third-/fourth-degree perineal tear; significant bleeding during the episiotomy repair; major tear or significant traumatic neonatal lesion.ResultsA total of 143 nulliparous women were included in the study (82 vacuum-assisted deliveries and 61 forceps-assisted deliveries), with 20 fetuses in occiput posterior position. Forty-seven operative deliveries were classified as complicated deliveries (28 vacuum-assisted deliveries, 19 forceps-assisted deliveries). No differences in obstetric, intrapartum or neonatal characteristics were observed between the study groups, with the following exceptions: birthweight (3229482 uncomplicated deliveries vs. 3623 +/- 406 complicated deliveries;