abnormallabour

Abnormal Labourpage 211Normal labour 3 elements :n expulsive forcen birth canaln fetusAbnormal labour Abnormalities of the expulsive forces Abnormalities of the fetus Abnormalities of the maternal pelvisAbnormal expulsive force Uterine dysfunctionwhypotonic uterine dysfunctionwhypertonic uterine dysfunctionHypotonic uterine dysfunction Effective contraction:n uterine activity is sufficient to make the cervix effacement and dilatation, fetus descent.Etiology Cephalopelvic disproportion or fetal malposition abnormal uterus psychological factors endocrinal dysfunction excessive sedation or conduction analgesiaClinical manifestation Coordinate hypotonic uterine dysfunction incoordinate hypotonic uterine dysfunction partogram: World Health Organization partographWorld Health Organization partograph A partogram was designed for use in developing countries (1992).Labour is divided into a latent phase ,which should last no longer than 8hours, and an active phase starting at 3cm dilatation, the rate of which should be no slower than 1cm per hour. A 4-hour wait(lag time) is recommended before intervention when the active phase is slow. Labor is graphed and analysis includs use of alert and action lines. The protocol was found to be beneficial in Southeast Asia.(WHO,1994)7 concepts Prolonged latent phase:16 hr prolonged active phase:8 hr arrest active phase:0cm/2hr prolonged second-stage labor:2hr/1hr arrest second-stage labor:0cm/1hr delayed descent:=0cm/hrTreatment Enhance the uterine contractibility the goal is to affect uterine activity that is sufficient to produce cervical change and fetal descent while avoiding uterine hyperstimulation and fetal distress.Hypertonic uterine contraction Localized abnormalities of uterine actionn constriction ringn pathological retraction ringw localized rings or constrictions of the uterus develop in association with prolonged labors, which is often the result of obstructed labor, with marked streching and thinning of the lower uterine segment. The ring may be seen clearly as an abdominal indentationand signifies impending rupture of the lower uterine segment.Generalized abnormalities of uterine action Precipitate labor:n extremely rapid-laborn total duration less than 3 hourswabnormally low resistancewabnormally strong uterine and abdominal contractionswvery rarely, the consequence of painful sensations and thus a lack of awareness of vigorous labor.DystociaSecond part: abnormalities of birth canalPelvic contraction Birth canaln bony canaln soft canal abnormal bony canal: pelvic contractionn any contraction of the pelvic diameters that diminishes the capacity of the pelvis can creat dystocia during laborClassification Contraction of the pelvic inlet contraction of the midpelvis and pelvic outlet general contraction of the pelvis pelvic deformitiesContracted pelvic inlet Anteroposterior d10cm diagonal conjugate d11.5cm external conjugate d18cmn simple flat pelvisn rickets flat pelvisContracted midpelvis Midpelvis: from inferior margin of the symphysis pubis through the ischial spines,touches the sacrum near the junction of the 4th and 5th vertebrae contraction: interischial spinous diameter is smaller than 8cm(spines are prominent, the pelvic side walls converge or the sacrosciatic notch is narrow)Contracted pelvic outlet Defination: diminition of the interischial tuberous diameter to 8cm or less. 2 triangles:n baseof both: interischial tuberous diametern anterior trianglen posterior trianglepicture1Outlet contraction without concomitant midplane contraction is rare Funnel shaped pelvis transversely contracted pelvisGeneral contraction of the pelvis2cm or more shorter than normalPelvic deformitiesosteomalacic pelvisobliquely contracted pelvisEffects on mather and fetus MOTHER:Inlet n Malpresentation and malpositionn prolonged laborn insufficient uterine contraction midpelvis and outletn persistant occipitotransverse or occipitoposterior positionn fistula formationn intrapartum infectionn threatening rupture or rupturefetus PROM Prolapse Distress (HI,IVH) Death Injury InfecionSoft birth canal Lower segment of uterus cervix vaginal Fetal malposition Occipitoanterior position 90% malposition 10%wabnormal cephalic posion 6-7%wbreech presentation 3-4%wothersPersistant occipitoposterior (transverse) position Causesn abnormal pelvis:transverse narrowing of the midpelvisn flexion not welln hypotonic uterine dysfunctionBreech presentation Incidencen breech presentation is common remote from term.n 3-4% of singleton deliveries Positionn LSA, LST LSP. RSA, RST, RAPCauses Uterine relaxation limited uterine cavity fetal head obstructedclassification Frank breech pn the lower extremities are flexed at the hips and extended at the knees, and thus the feet lie in close proximity to the head.n It appears most commonly complete breech pn differs in that one or both knees are flexed. Incomplete breech pn one or both hips are not flexed and one or both feet or knees lie below the breech, that is, a foot or knee is lowermost in the birth canal.Incomplete breech presentationEffects Maternaln greater frequency of operative deliveryn higher maternal morbidity and slightly higher mortalityn PROMn secondary hypotonic uterine dysfunctionn puerperium infectionn postpartum haemorrhagen laceration of cervixEffects Fetusn PROMn cord prolapsen fetal distress even deathn newborn asphyxian brachial plexus injuryn IVHFace presentationCompound presentation问题： 决定正常分娩的因素有哪些？ 什么情况下能出现异常分娩？分娩室内 产妇停经 39周，规律宫缩 20小时。 查体： T36.9, Bp120 85mmHg， P84次 /min ，R20次 /min ，宫缩 10 20秒 /9 6min，强度弱，胎位 LOA，胎心 156次 /min 内诊：宫颈消，宫口开大 2cm，先露头 S-2， 骨盆检查未见异常问题： 产程进展的情况如何？为什么？ 将如何避免？难产 （ dystocia） 产 力 异 常 产道 异常 胎儿 异常产产 力力 异异 常常（ abnormal uterine action）内 容 定义 (definition) 分类 (classification) 子宫收缩乏力 （ uterine inertia） 子宫收缩过强 （ uterine hypercontractility）一、定义一、定义 (definition) 产力中以 子宫收缩力 为主 在分娩过程中，子宫收缩的节律性 、 对称性 及 极性 不正常或 强度 、 频率 有改变二、分类二、分类 (classification)原发性协调性（低张性）乏力 继发性不协调性（高张性）子宫收缩力异常 急产（无阻力时） 协调性病理缩复环（有 阻力时）过强强直性子宫收缩不协调性子宫痉挛性狭窄环 (一）子宫收缩乏力 （ uterine inertia） 原因 (etiology) 临床表现 (Clinical manifestation) 诊断 (diagnosis) 母儿影响（ effect) 预防 (prevention) 处理（ management)1.原因原因 (etiology) 头盆不称或胎位异常 子宫因素 精神因素 内分泌失调 药物影响 其他2.临床表现及诊断临床表现及诊断(Clinical manifestation and diagnosis) 协调性宫缩乏力（低张性宫缩乏力 hypotonic uterine inertia） 不协调性宫缩乏力（高张性宫缩乏力 hypertonic uterine inertia )协调性宫缩乏力（低张性宫缩乏力）协调性宫缩乏力（低张性宫缩乏力） 分类： 原发性、继发性 症状： 子宫收缩有正常的节律性、对称性和极性，收缩力弱，持续短、间歇长且不规率。 体症： 宫缩高峰时，手指压宫底部出现凹陷宫腔内压力 15mmHg 常见： 中骨盆与骨盆出口平面狭窄、持续性枕横位和枕后位等，多属继发性宫缩乏力。低张性宫缩乏力低张性宫缩乏力不协调性宫缩乏力（高张性宫缩乏力） 症状： 极性倒置，节律不协调 体症： 宫口扩张缓慢，胎先露部下降停滞，属无效宫缩。 常见： 于胎位异常和头盆不称，多属原发性宫缩乏力。 鉴别方法 给予强镇静剂3.诊断（ diagnosis） 潜伏期延长 活跃期延长 活跃期停滞 第二产程延长 第二产程停滞 胎头下降延缓 胎头下降停滞 滞产 (1) 潜伏期延长潜伏期延长 （ prolonged latent phase） 从规律宫缩至宫口开大 3cm， 16小时 称为潜伏期延长 (正常 8小时 ) (2) 活跃期延长活跃期延长 （ prolonged active phase） 从宫口开 3cm至宫口开全超 8小时称为 活跃期延长 (正常 4小时 )(3)活跃期停滞活跃期停滞 （ protracted active phase） 进入 活跃期后，宫口不在扩张 2小时 ，称为活跃期停滞（ 4） 第二产程延长（第二产程延长（ prolonged second stage） 第二产程初产妇 2小时 ，经产妇 1小时 尚未分娩者，称为 第二产程延长（ 5） 第二产程停滞（ protracted second stage） 第二产程达 1小时 胎头下降无进展，称 第二产程停滞（ 6） 胎头下降延缓 （ prolonged descent） 活跃期晚期胎头至宫口扩张 9 10cm，胎头下降速度每小时 1cm，称 胎头下降延缓（ 7） 胎头下降停滞 （ protracted descent） 活跃期晚期胎头停留在原处不下降 1小时 ，称 胎头下降停滞（ 8） 滞产（ prolonged labor） 总产程 24小时 以上，称 滞产4.母儿影响（母儿影响（ effect） 产妇： 宫缩乏力、脱水、酸中毒、低钾血症、膀胱阴道瘘、尿道阴道瘘、生殖道感染、产后出血。 胎儿： 增加手术产机会、胎儿窘迫、胎死宫内5.预防预防 (prevention) 重视产前宣教，增强分娩信心 建设康乐待产室 分娩前注意补充营养 避免使用过多的镇静药 及时发现胎位异常 及时排空膀胱和直肠6.处理（处理（ management） 协调性宫缩乏力 不协调性宫缩乏力（ 1） 协调性宫缩乏力 第一产程： 一般处理 ：饮食、灌肠、排尿加强宫缩 ：人工破膜、安定静推缩宫素、前列腺素、针刺穴位 第二产程： 加强宫缩及时行助产术剖宫产 ：胎头未衔接、胎儿窘迫 第三产程： 预防产后出血抗生素预防感染（ 2）不协调性宫缩乏力 调节子宫收缩，给予 镇静剂 头盆不称 或 胎儿窘迫 ，及时行 剖宫产（二） 子宫收缩过强（ uterine hypercontractility） 协调性子宫收缩过强 不协调性子宫收缩过强1.强直性子宫收缩2.子宫痉挛性狭窄环 1.协调性子宫收缩过强【 对母儿影响 】 产妇 ：子宫破裂、软产道裂伤、产褥感染、胎盘滞留、产后出血。 胎儿及新生儿 ：胎儿窘迫，新生儿窒息、颅内出血、感染、骨折、死亡。 急产： 总产程 3小时 。1.协调性子宫收缩过强协调性子宫收缩过强【 处理 】 提前住院待产 提前作好接产准备 提前作好抢救新生儿窒息准备 预防新生儿颅内出血 及时缝合软产道裂伤 预防感染2.不协调性子宫收缩过强不协调性子宫收缩过强 强直性子宫收缩 子宫痉挛性狭窄环（ constriction ring)(1)强直性子宫收缩【 临床表现 】 产妇烦躁不安，持续性腹痛，拒按，血尿。 胎位胎心不清，病理性缩复环。【 处理 】 抑制宫缩 剖宫产(2)子宫痉挛性狭窄环 （ constriction ring)【 定义 】 子宫壁局部肌肉痉挛性不协调性收缩形成环状狭窄持续不放松，称 子宫痉挛性狭窄环【 原因 】紧张、过度疲劳、宫缩剂应用不当、操作粗暴。(2)子宫痉挛性狭窄环 （ constriction ring)【 临床表现 】持续性腹痛、产程进展缓慢、胎心时快时慢、内诊 :触及