头位难产采用徒手胎头旋转术的时机探讨

持续性枕横位、枕后位 ,是导致头位难产的重要原因之一。适时采用手法旋转 ,可缩短产程 ,减少产妇痛苦 ,降低剖宫产率。本文对持续性枕横位及持续性枕后位的产妇在不同时期施行徒手旋转胎头纠正胎方位 ,使难产转为顺产 ,取得了不同的效果 ,现报道如下。1　资料与方法1.1　一般资料　我院自 1997年 5月至 2 0 0 0年 12月分娩总数 3 4 95例 ,难产 14 5 6例 ,发生头位难产 70 9例 ,占难产总数的 4 8 69%,其中 3 2 3例宫颈扩张进入活跃期出现延缓或停止。随机分为三组 ,Ａ组 :宫口扩张 6～ 7ｃｍ ,先露在坐骨棘平至棘下 1 5ｃｍ ,枕横位 12 2例 …     

202例纠正枕横(后)位的临床探讨

目的探讨改变体位结合徒手旋转胎头在胎方位异常时的临床意义。方法选择2010年10月至2012年5月202例单胎头位,枕横(后)位无严重合并症、并发症的产妇,将其分为研究组102例,在首次发现胎方位异常时采取改变体位,待宫口开大>6cm、胎先露>S+1手转胎头;对照组100例,发现胎方位异常时采取改变体位并严密观察产程进展。结果研究组阴道分娩率(96.08%vs83%)明显高于对照组,差异有高度统计学意义(P<0.01)。产程时间缩短[(400±65)minvs(504±98)min]、经阴道分娩的产妇产后出血≥300ml者研究组较对照组明显减少(0%vs6.02%)、软产道裂伤减少(30.61%vs54.22%)、新生儿窒息率降低(1.96%vs50%),差异均有统计学意义(P<0.05)。结论改变体位结合徒手旋转胎头可使枕横(后)位致产程异常者转化为成功的阴道分娩,阴道分娩率明显升高,产程时间缩短,母儿合并症、并发症发生率明显降低。     

产程中产妇取坐位矫正头位异常探讨

胎头方位异常是头位难产的主要原因 ,手术率极高 ,处理不当时对母婴危害大 ,争取于产程早期发现 ,并及时采用适宜的措施给予纠正 ,将难产转为顺产 ,以提高分娩质量。一、资料和方法1.资料 :1996年 3月至 1999年 6月间 ,选择宫口开大 3cm,常规人工破膜 ,了解羊水情况 ,阴道检查与 B超检查胎方位为枕后位者 30 0例 ,分为研究组和对照组 ,每组 15 0例 ,均为初产妇 ,年龄 2 1～ 35岁 ,孕周 37～ 41周 ,均为单胎头位 ,骨盆内外测量无异常 ,无严重的妊娠并发症及合并症。2 .方法 :(1)确定胎方位方法 :自然临产或计划性分娩、宫口开大 3cm时 ,行人…     

手转胎头术纠正枕位异常的临床评价

在头位难产中，以枕位异常发生率最高，为了保障母子健康，降低头位难产发生率，降低剖宫产率，我院对第一产程活跃期胎头下降阻滞的枕位异常，采用手转胎头辅以经腹推儿背联合手法纠正，取得满意效果。现报告如下。     

头、臀位难产专题座谈会纪要

中华妇产科杂志和实用妇科与产科杂志编辑部于1985年11月在辽宁省沈阳市联合召开了一次“头、臀位难产”专题座谈会。现将座谈讨论的主要内容整理如下。一、关于头位性难产会议选出头位性难产论文22篇,大会交流19篇,其余在分组会上交流。主要讨论了下列问题: 1.关于持续性枕后位及枕横位枕后位发生率占分娩总数的1.52％(北医)、1.22％(山西)及1.08％(皖南医)。关于持续性枕后位的定义有两种提法:①在第一产程晚期或第二产程初期,儿头双顶径通过坐骨棘间径而末完成内回转,枕部仍位于骨盆的側后方或后方者;②儿头以枕后位进入骨盆,经过充分试产至必须结束分娩时(不论宫口开大多少及儿头位置高低),胎头枕部持续于骨盆侧后方者,应诊为持续性枕     

分娩期综合性干预预防持续性枕后位的研究

目的研究产程不同时相干预预防持续性枕后位的措施，以降低持续性枕后位的发生率，改善分娩结局。方法将９６例枕后位产妇随机平均分为两组，对研究组的产妇施行针对产程不同时相的一系列干预措施，包括人工破膜、纠正异常胎轴、产妇采取与胎背同侧的高坡侧俯卧位、徒手扩张宫颈及徒手旋转胎头。结果研究组活跃期及第二产程较对照组短，研究组活跃期先露下降平均速度及宫口扩张平均速度均快于对照组，研究组的持续性枕后位发生率及胎儿窘迫发生率均低于对照组，产后出血量少于对照组（Ｐ＜０．０５）。结论综合性干预措施安全、有效、易行。     

剖宫产术后子宫卒中一例

患者32岁,1986年12月13日因妊娠40周,临产,急诊入院。孕期从未做过产前检查。两年前第一胎足月,产钳助产,新生儿“颅内出血”死亡。检查:宫高33cm,腹围94cm,胎方位:LOA,胎头衔接,胎心140次/分,宫缩30″/5—6′。肛查:宫口开大5cm。入院1小时后人工破膜,羊水清。阴道检查:胎儿呈左枕横位,胎头S~(+0.5),并有轻度变形,宫口开大8cm。双侧坐骨棘不凸,骶骨岬未触及,骶骨上段较平直。产力欠佳,给予0.5%催产素静滴加强宫缩,3小时后宫口开全。查:先露部S~(+1.5),胎头变形明显,骨缝有重叠,先锋头约3cm,因倾势不均,立即行剖宫产术。     

再谈头位阴道助产术

头先露的阴道助产术包括产钳助产术和胎头负压吸引术。在第二产程中判断胎头位置及胎方位是阴道助产成功的关键。胎头最低位置于坐骨棘2 cm以下,胎方位为枕前位者,助产风险相对小。产科医生要严格把握阴道助产的手术指征,并与患者充分沟通。临床医生的判断能力,培训经历以及临床经验是助产成功的重要因素。     

胎儿体重对持续性枕后位产程特征和分娩结局影响的分析

目的:探讨胎儿体重对持续性枕后位产程特征和分娩结局的影响.方法:对2005年12月至2009年12月在本院产科住院分娩228例持续性枕后位产妇的临床资料进行回顾性分析,根据新生儿出生体重分为对照组112例(胎儿体重≥2500 g且＜3500 g)和研究组116例(胎儿体重≥3500 g且＜4250 g).并将两组产程特征、母儿结局进行分析比较.结果:两组产妇产程异常(宫口扩张延缓、停滞,胎头下降延缓、停滞)发生率、临床干预(体位矫正、手转胎头)成功率、剖宫产率、母儿并发症(产后出血、产褥病率、胎儿窘迫、新生儿窒息)发生率差异均有统计学意义(P＜0.05).结论:持续性枕后位产程处理中充分考虑胎儿的体重因素,对于胎儿估计体重≥3500 g的枕后位病例应积极临床干预,干预失败应放宽手术指征,以降低母儿并发症发生率.     

头足复合位误诊为臀位一例

患者24岁,住院号82290。因孕足月临产入院。检查:宫底位于剑下二横指,在右侧脐横线上听到胎心音,胎心率140次/分,宫缩规律。内诊检查:宫颈消失,宫口开大5cm,已破膜,先露为双足,位于棘上5cm。初步诊断臀位。患者入院后产程进展缓慢,遂行催产素静脉点滴(500ml 液体中加催产素3U)。用药后,产程略有进展,但规律宫缩20小时宫口开大9cm,双足仍位于棘上2cm。因已出现胎儿宫内窘迫(胎心率快慢不一),即决定行剖宫产术。取子宫下段横切口,取胎儿时,发现是头足复合位(即双足在宫腔右下方,胎头紧贴双足)。迅速行头位娩出一苍白窒息男婴。经急救,新生儿存活,但其右下肢外侧踝     

Fetal head position during the second stage of labor: comparison of digital vaginal examination and transabdominal ultrasonographic examination

OBJECTIVE: To study the correlation between digital vaginal and transabdominal ultrasonographic examination of the fetal head position during the second stage of labor. METHODS: Patients (n = 110) carrying a singleton fetus in a vertex position were included. Every patient had ruptured membranes and a fully dilated cervix. Transvaginal examination was randomly performed either by a senior resident or an attending consultant. Immediately afterwards, transabdominal ultrasonography was performed by the same sonographer (OD). Both examiners were blind to each other's results. Sample size was determined by power analysis. Confidence intervals around observed rates were compared using chi-square analysis and Cohen's Kappa test. Logistic regression analysis was performed. RESULTS: In 70% of cases, both clinical and ultrasound examinations indicated the same position of the fetal head (95% confidence interval, 66-78). Agreement between the two methods reached 80% (95% CI, 71.3-87) when allowing a difference of up to 45 degrees in the head rotation. Logistic regression analysis revealed that gestational age, parity, birth weight, pelvic station and examiner's experience did not significantly affect the accuracy of the examination. Caput succedaneum tended to diminish (p = 0.09) the accuracy of clinical examination. The type of fetal head position significantly affected the results. Occiput posterior and transverse head locations were associated with a significantly higher rate of clinical error (p = 0.001). CONCLUSION: In 20% of the cases, ultrasonographic and clinical results differed significantly (i.e., >45 degrees). This rate reached 50% for occiput posterior and transverse locations. Transabdominal ultrasonography is a simple, quick and efficient way of increasing the accuracy of the assessment of fetal head position during the second stage of labor.     

Asynclitism: a literature review of an often forgotten clinical condition

Asynclitism is defined as the “oblique malpresentation of the fetal head in labor”. Asynclitism is a clinical diagnosis that may be difficult to make; it may be found during vaginal examination. It is significant because it may cause failure of progress operative or cesarean delivery. We reviewed all literature for asynclitism by performing an extensive electronic search of studies from 1959 to 2013. All studies were first reviewed by a single author and discussed with co-authors. The following studies were identified: 8 book chapters, 14 studies on asynclitism alone and 10 papers on both fetal occiput posterior position and asynclitism. The fetal head in a laboring patient may be associated with some degree of asynclitism; this is seen as usual way of the fetal head to adjust to maternal pelvic diameters. However, marked asynclitism is often detected in presence of a co-existing fetal head malposition, especially the transverse and occipital posterior positions. Digital diagnosis of asynclitism is enhanced by intrapartum ultrasound with transabdominal or transperineal approach. The accurate diagnosis of asynclitism, in an objective way, may provide a better assessment of the fetal head position that will help in the correct application of vacuum and forceps, allowing the prevention of unnecessary cesarean deliveries.     

Study Protocol. IDUS -- Instrumental delivery & ultrasound. A multi-centre randomised controlled trial of ultrasound assessment of the fetal head position versus standard care as an approach to prevent morbidity at instrumental delivery

ABSTRACT: BACKGROUND: Instrumental deliveries are commonly performed in the United Kingdom and Ireland, with rates of 12 -- 17% in most centres. Knowing the exact position of the fetal head is a pre-requisite for safe instrumental delivery. Traditionally, diagnosis of the fetal head position is made on transvaginal digital examination by delineating the suture lines of the fetal skull and the fontanelles. However, the accuracy of transvaginal digital examination can be unreliable and varies between 20% and 75%. Failure to identify the correct fetal head position increases the likelihood of failed instrumental delivery with the additional morbidity of sequential use of instruments or second stage caesarean section. The use of ultrasound in determining the position of the fetal head has been explored but is not part of routine clinical practice. METHODS: A multi-centre randomised controlled trial is proposed. The study will take place in two large maternity units in Ireland with a combined annual birth rate of 13,500 deliveries. It will involve 450 nulliparous women undergoing instrumental delivery after 37 weeks gestation. The main outcome measure will be incorrect diagnosis of the fetal head position. A study involving 450 women will have 80% power to detect a 10% difference in the incidence of inaccurate diagnosis of the fetal head position with two-sided 5% alpha. DISCUSSION: It is both important and timely to evaluate the use of ultrasound to diagnose the fetal head position prior to instrumental delivery before routine use can be advocated. The overall aim is to reduce the incidence of incorrect diagnosis of the fetal head position prior to instrumental delivery and improve the safety of instrumental deliveries.Trial registrationCurrent Controlled Trials ISRCTN72230496.     

Occiput posterior fetal head position increases the risk of anal sphincter injury in vacuum-assisted deliveries

OBJECTIVE: The purpose of this study was to determine whether an occiput posterior (OP) fetal head position increases the risk for anal sphincter injury when compared with an occiput anterior (OA) position in vacuum-assisted deliveries. STUDY DESIGN: We conducted a retrospective cohort study of 393 vacuum-assisted singleton vaginal deliveries. Maternal demographics and obstetric and neonatal data were collected from an obstetric database and chart review. RESULTS: Within the OP group, 41.7% developed a third- or fourth-degree laceration compared with 22.0% in the OA group (OR 2.5, 95% CI 1.4-4.7). In a logistic regression model that controlled for BMI, race, nulliparity, length of second stage, episiotomy, birth weight, head circumference, and fetal head position, OP position was 4.0 times (95% CI 1.7-9.6) more likely to be associated with an anal sphincter injury than OA position. CONCLUSION: Among vacuum deliveries, an OP head position confers an incrementally increased risk for anal sphincter injury over an OA position.     

Does fetal head position at the term plus 12 scan influence induction, labor and delivery outcome?

AIMS: To assess the influence that fetal head position has on induction, labor and delivery outcome for both mother and baby. METHODS: During a one month period, in November 1999, all women attending for a post-dates scan were enrolled as the study population. In total, 91 women formed our study population for analysis of data. The sonographic, induction and labor details of all women were recorded on a dedicated data sheet. As well as documenting the maternal age, parity, liquor volume (mm) and BPS, the position of the fetal head was noted by the sonographer as occipitoanterior, occipitotransverse or occipitoposterior. All women had gestation confirmed by ultrasound early during the course of their pregnancy. Maternal, ultrasonographic, induction and labor variables were correlated with fetal head presentation at scan. RESULTS: There was no positive correlation found between fetal head position at the term plus 12 scan and associated induction, labor or delivery complications in the 91 women studied. CONCLUSIONS: Our study shows no positive correlation between fetal head position and induction, labor or delivery complications.     

Effect of location of the sensor on reflectance pulse oximetry

Objective The influence of the location of the sensor on reflectance pulse oximetry during fetal monitoring in labour was investigated using the newborn infant as a model.
Methods Seven healthy infants were studied between 19 and 48 hours after term delivery. Recordings of reflectance pulse oximetry were obtained from eight different sites on the infant's head. The relative changes in red to infrared light (R/IR) were determined. In pulse oximetry R/IR values are converted to arterial oxygen values by means of an empirically derived calibration curve.
Results Significantly lower R/IR values were found at the forehead compared with the fontanelle, the parietal and occipital position, and the temporal area. Conversion to oxygen saturation values revealed a difference of up to 13.4% in oxygen saturation between the forehead and the occipital area.
Conclusion Assuming that the arterial blood oxygen saturation did not change substantially, our findings indicate that in reflectance pulse oximetry there is no unique relation between R/IR and arterial oxygen saturation. The differences in reflectance pulse oximetry at the various sites are explained by differences in optical properties (scattering and absorption) of the tissue underneath the sensor. These will affect the red and infrared light reaching the detectors in a different way, and consequently R/IR changes. Because during intrapartum monitoring exact positioning of the sensor on the fetal head is usually impossible, the accuracy of fetal reflectance pulse oximetry is impaired.     

持续性枕横位及枕后位的产程特点及围产儿预后

目的：探讨持续性枕横位及枕后位的产程特点及围产儿预后。方法：采用回顾性资料分析方法，对１９９５年１１月至１９９６年７月在我院分娩的持续性枕横位及枕后位孕妇的临床资料进行分析。并与同期枕位正常的９０例（对照组）孕妇进行比较。结果：枕位异常者，胎儿体重过大、宫缩乏力的比例明显增加，产程各期时间均明显延长，胎先露下降速度明显减慢，各产程异常发生率明显增加，手术产率明显增加。枕横位总手术产率为８２．８１％，枕后位为９２．３１％，胎儿宫内缺氧、新生儿窒息率明显增加。结论：持续性枕横位及枕后位是难产的主要原因之一，若处理不当，围产儿预后欠佳。     

Intrapartum sonography to determine fetal head position

Objective: To investigate the accuracy of intrapartum transvaginal digital examination in defining the position of the fetal head. Patients and methods: In 496 singleton pregnancies in labor at term, the fetal head position was determined by routine transvaginal digital examination by the attending midwife or obstetrician. Immediately before or after the clinical examination, the fetal head position was determined using transabdominal ultrasound by an appropriately trained sonographer who was not aware of the clinical findings. The digital examination was considered to be correct if the fetal head position was within 45° of the ultrasound finding. The accuracy of the digital examination was examined in relation to maternal characteristics and the progress of labor. Results: The position of the fetal head was determined by ultrasound examination in all 496 cases examined. Digital examination failed to define the fetal head position in 166 (33.5%) cases and, in 330 cases where the position was determined, the findings of the digital and sonographic examinations were in agreement in only 163 (49.4%) cases. The rate of correct identification of the fetal position by digital examination increased with cervical dilatation, from 20.5% at 3–4 cm to 44.2% at 8–10 cm, and was higher if the examination was carried out by an obstetrician than a midwife (50% versus 30%) and if there was absence rather than presence of caput (33% versus 25%). Conclusions: Routine digital examination during labor fails to identify the correct fetal position in the majority of cases.     

Randomized Controlled Trial of Hands‐and‐Knees Positioning for Occipitoposterior Position in Labor

ABSTRACT: Background: Hands‐and‐knees positioning during labor has been recommended on the theory that gravity and buoyancy may promote fetal head rotation to the anterior position and reduce persistent back pain. A Cochrane review found insufficient evidence to support the effectiveness of this intervention during labor. The purpose of this study was to evaluate the effect of maternal hands‐and‐knees positioning on fetal head rotation from occipitoposterior to occipitoanterior position, persistent back pain, and other perinatal outcomes. Methods: Thirteen labor units in university‐affiliated hospitals participated in this multicenter randomized, controlled trial. Study participants were 147 women laboring with a fetus at ≥37 weeks’ gestation and confirmed by ultrasound to be in occipitoposterior position. Seventy women were randomized to the intervention group (hands‐and‐knees positioning for at least 30 minutes over a 1‐hour period during labor) and 77 to the control group (no hands‐and‐knees positioning). The primary outcome was occipitoanterior position determined by ultrasound following the 1‐hour study period and the secondary outcome was persistent back pain. Other outcomes included operative delivery, fetal head position at delivery, perineal trauma, Apgar scores, length of labor, and women's views with respect to positioning. Results: Women randomized to the intervention group had significant reductions in persistent back pain. Eleven women (16%) allocated to use hands‐and‐knees positioning had fetal heads in occipitoanterior position following the 1‐hour study period compared with 5 (7%) in the control group (relative risk 2.4; 95% CI 0.88–6.62; number needed to treat 11). Trends toward benefit for the intervention group were seen for several other outcomes, including operative delivery, fetal head position at delivery, 1‐minute Apgar scores, and time to delivery. Conclusions: Maternal hands‐and‐knees positioning during labor with a fetus in occipitoposterior position reduces persistent back pain and is acceptable to laboring women. Given this evidence, hands‐and‐knees positioning should be offered to women laboring with a fetus in occipitoposterior position in the first stage of labor to reduce persistent back pain. Although this study demonstrates trends toward improved birth outcomes, further trials are needed to determine if hands‐and‐knees positioning promotes fetal head rotation to occipitoanterior and reduces operative delivery. (BIRTH 32:4 December 2005)