Presentation on theme: "ANTENATAL AND INTRAPARTUM"— Presentation transcript:
1 ANTENATAL AND INTRAPARTUM FETAL SURVEILLANCEUSGDopplerCTGECG
2 MAJOR CAUSES OF PERINATAL LOSS Fetal abnormalityPreterm deliveryChronic utero – placental insufficiencyAcute HypoxiaUnexplained intrauterine deathOthers
3 MODALITIES OF ANTENATAL FETAL SURVEILLANCE Detection of fetal abnormalitiesAssessment of fetal growthMonitoring of fetal well-beingOthers
4 APPROACH TO ANTENATAL MONITORING OF FETAL GROWTH AND WELL-BEING Confirmation of gestational ageClinical methods of monitoringInvestigations
5 DYNAMIC PARAMETERS To monitor fetal dynamic response to chronic utero-placental insufficiencyAFI – renal perfusionUmbilical arterial flow (A/B ratio)– fetal peripheral and placental circulationCerebral arterial flow (MCA) – head sparing effect
6 FETAL MONITORINGFetal distress is defined in terms of the manifestation ofthe fetal hypoxia (by changes in the fetal heart rate FHRor fetal blood pH)SIGNIFICANCES OF FETAL DISTRESSHypoxic damage to the foetus is difficult to quantify,but the effect can be devastating.- neurological abnormalities - cerebral palsy andmental retardations- fetal death – results from severe intrapartumasphyxia
7 BASIC DEFINITIONSHYPOXAEMIA - decrease in the oxygen content of the arterial blood aloneHYPOXIA - decrease in the oxygen contentthat affects the peripheral tissuesASPHYXIA - general oxygen deficiency that affects the high priority organs as well
8 PATHOPHYSIOLOGY OF FETAL HYPOXIA In the absence of stress, the fetus is neither acidoticnor hypoxic. An adequate delivery of oxygen to the tissues occurs despite the low fetal arterial partial pressure of oxygen (pO2).The transfer of oxygen across the placenta to the fetus is enhanced by following mechanisms :- fetal cardiac output and systematic blood flowrates are higher than those of the adult.- the affinity of fetal blood for the oxygen and - the fetal oxygen – caring capacity, both ofwhich are greater than those of an adult
9 PATHOPHYSIOLOGY OF CHRONIC FETAL COMPROMISE utero-placental insufficiencyreduced pO2 to fetal CNSredistribution of fetal cardiac outputperfusion to CNS & heart perfusion to peripheral & viscerarenal perfusion visceral circulationOLIGOHYDRAMNIOSbowel distension umbilical arterial resistancemeconium peritonitisnecrotising enterocolitis etc
11 A decreased amniotic fluid volume is frequently one of the first clues to an underlying fetalabnormality. The sonographer/sonologist should,therefore, have a basic understanding of themechanisms responsible for normal amnioticfluid production. Once the derivation of amnioticfluid is understood, the potential mechanismsthat can result in oligohydramnios can be betterappreciated.
12 Etiology of Oligohydramnios 1. intrauterine growth restriction post-term pregnancies preterm rupture of the membranes fetal anomalies and/or aneuploidy iatrogenic
13 30 week gestation. A single deepest pocket of amniotic fluid (7 cm),indicating a normal amniotic fluid volume.Visually normal amniotic fluidvolume at 18 weeks' gestation.1.8 cm pocket of amniotic fluid indicatingoligohydramnios. The color box confirmsthat umbilical cord is not present in thepockets of amnioticSubjective assessment of amniotic fluid volume.20 week fetus with a unilateral multicystic kidneyand congenital absence of the other kidney,resulting in anhydramnios
14 Oligohydramnios due to bilateral renal agenesis. Transabdominal ultrasound at 20 weeks' gestation.
15 An amniotic fluid index of 4.2 cm, indicating oligohydramnios there is an absence of amniotic fluid in the upper quadrants.The color box to the right of the image indicates the presenceof umbilical cord.
16 19 week fetus with Turner's syndrome, cystic hygroma (arrows) and oligohydramnios.15 week fetus with posterior urethral valves.The bladder (b) is massively distended.Enlarged "key-hole" bladder associatedwith posterior urethral valves.
17 Amniotic fluid has a number of important roles in embryo/fetal development:1. Permitting fetal movement and the developmentof the musculoskeletal system.2. Swallowing of amniotic fluid enhances the growthand development of the gastrointestinal tract.3. The ingestion of amniotic fluid provides some fetalnutrition and essential nutrients.
18 Amniotic fluid has a number of important roles in embryo/fetal development:4. Amniotic fluid volume maintains amniotic fluidpressure thereby reducing the loss of lung liquidan essential component to pulmonary development.5. Protects the fetus from external trauma.6. Protects the umbilical cord from compression.7. It's constant temperature helps to maintainthe embryo's body temperature.8. It's bacteristatic properties reduces thepotential for infection.
19 STRESSED FETUSWhen perfusions is decreased because of impaired uterine or umbilical blood flow , the transfer of oxygen to the fetus is diminished, and the results is an accumulations of carbon dioxide in the fetus.1. Increased carbon dioxide causes an increase in the partial pressure of carbon dioxide (pCO2) and a concomitant fall in pH, analogous to adult respiratory acidosis.2. Continued hypoxia deprives the fetus of sufficient oxygen to perform the aerobic reactions, resulting in buildup of organic acids with the accumulation of pyruvic and lactic acids resulting in metabolic acidosis
20 STRESSED FETUS 3. Transient decreases in the fetal or uterine perfusions usually cause a short-lived respiratory acidosis, whereas more prolonged or profound decreases results in a combined respiratory and metabolic acidosis4. fetal oxygen deprivation usually results in theFHR or fetal bradycardia
21 FETAL DEFENCE MECHANISMS Increased tissue oxygen extractionReduced non-essential activityIncreased sympathetic activityRedistribution of blood flowAnaerobic metabolism with the metabolismof blood sugar – glucolysis, andglycogen - glycogenolisis
22 Hypoxia Asphyxia More effective uptake of oxygen sO2 Reduced activity Decrease in growth rateMaintained energy balancesO2HipoxaemiaHypoxiaAsphyxiadays and weeks hours minutestFETAL RESPONSE TO HYPOXAEMIA
23 Hypoxia Asphyxia sO2 Surge of stress hormones Redistribution of blood flowPeripheral tissue anaerobic metabolismMaintained energy balanceHipoxaemiaHypoxiaAsphyxiadays and weeks hours minutestFETAL RESPONSE TO HYPOXIA
24 Hypoxia Asphyxia sO2 Alarm reaction Anaerobic metabolism in the central organsThe heart fails to functionHipoxaemiaHypoxiaAsphyxiadays and weeks hours minutestFETAL RESPONSE TO ASPHYXIA
25 ANTENATAL AND INTRAPARTUM FETAL SURVEILLANCECardiotocographyContraction stress testNonstress testBiophysical profileFetal movement countsUmbilical artery Doppler velocimetryFetal electrocardiographyFetal pulse oxymetryFetal blood sampling
26 Fetal and Sequence of Fetal Deterioration Neurodevelopment CST=contraction stress test; NST=nonstress test; BPP=biophysical profile.
27 BIOPHYSICAL PROFILEbiophysical profile was first introduced in the late 1970s.It requires more expensive equipment and more highlytrained personnel than the other testing modalities.The study is based on the concept that hypoxic fetuseslose certain behavioral parameters in the reverse orderin which they were acquired in the course of fetal developmentIt evaluates indicators of chronic fetal hypoxia and placentalfunction, such as amniotic fluid volume, in addition to moreacute indicators, such as fetal breathing, movements and tone.
28 The gradual hypoxia concept Fetal CNS centres embriogenesis FT cortex PATHOPHYSIOLOGY OF BIOPHYSICAL VARIABLESThe gradual hypoxia conceptFetal CNS centres embriogenesisFT cortexFM cortex-nucleiFBM ventral surface of 4th ventricleFHR posterior hypothalamus medulla hypoxia
40 Term Definition 110-160 bpm 100-109 bpm 161-180 bpm <100 bpm Baseline fetal heart rateThe mean level of the FHR when this is stable, excluding accelerations and decelerations. It is determined over a time period of 5 or 10 minutes and expressed in bpm. Preterm fetuses tend to have values towards the upper end of this range. A trend to a progressive rise in the baseline is important as well as the absolute valuesNormal Baseline FHRbpmModerate bradycardiabpmModerate tachycardiabpmAbnormal bradycardia<100 bpmAbnormal tachycardia180 bpm
41 Normal baseline variability The minor fluctuations in baseline FHR occuring at three to five cycles per minute. It is measured by estimating the difference in beats per minute between the highest peak and lowest trough of fluctuation in a one-minute segment of the traceNormal baseline variabilityGreater than 5 bpm between contractionsNon-reassuring baseline variabilityLess than 5 bpm for 40 minutes but less than 90 minutesAbnormal baseline variabilityLess than 5 bpm for 90 minutesAccelerationsTransient increases in FHR of 15 bpm or more and lasting 15 seconds or more. The significance of no accelerations on an otherwise normal CTG is unclear
42 Decelerations Early decelerations Variable decelerations Transient episodes of slowing of FHR below the baseline level of more than 15 bpm and lasting 15 seconds or moreEarly decelerationsUniform, repetitive, periodic slowing of FHR with onset early in the contraction and return to baseline at the end of the contractionVariable decelerationsUniform, repetitive, periodic slowing of FHR with onset mid to end of the contraction and nadir more than 20 seconds after the peak of the contraction and ending after the contraction. In the presence of a non-accelerative trace with baseline variability < 5 bpm, the definition would include decelerations < 15 bpmVariable, intermittent periodic slowing of FHR with rapid onset and recovery. Time relationships with contraction cycle are variable and they may occur in isolation. Sometimes they resemble other types of deceleration patterns in timing and shape
43 Atypical variable decelerations Variable decelerations with any of the following additional components:loss of primary or secondary rise in baseline rateslow return to baseline FHR after the end of the contractionprolonged secondary rise in baseline ratebiphasic decelerationloss of variability during decelerationcontinuation of baseline rate at lower levelProlonged decelerationAn abrupt decrease in FHR to levels below the baseline that lasts at least seconds. These decelerations become pathological if they cross two contractions, i.e. greater than 3 minutesSinusoidal patterna regular oscillation of the baseline long-term variability resembling a sine wave. This smooth, undulating pattern, lasting at least 10 minutes, has a relatively fixed period of 3--5 cycles per minute and an amplitude of bpm above and below the baseline. Baseline variability is absent
45 FETAL HEART RATE FEATURES CATEGORISATION OFFETAL HEART RATE FEATURES
46 ELEMENTS OF FHR PATTERN The baseline FHR – is the steady rate fetal that occursduring and between contractions in the absence ofaccelerations and decelerations . The normal baselineFHR is beats per minute.At 16 weeks , the average baseline is 160 BPM.The baseline FHR decreases approximately 24 BPMfrom 16weeks to term .
47 BEAT TO BEAT VARIABILITY represents the continuous interaction of the sympatheticand parasympathetic nervous system in adjusting theFHR to fetal metabolic or hemodynamic conditions.decreased variability may signify loss of fine autonomiccontrol of FHR- good variability usual predict a good fetal outcome
48 ABNORMAL FHR Asphyxia Drugs Prematurity Tachycardia DECREASEDVARIABILITYAsphyxiaDrugsPrematurityTachycardiaSleep state of fetusCardiac and CNSabnormalitiesArrythmiasFETALTACHYCARDIAAsphyxiaMaternal feverFetal infectionPrematurityDrugsFetal stimulationsArrythmiasMaternal anxietyThyreotoxicosisIdiopaticFETALBRADYCARDIAAsphyxiaDrugsReflex (pressureon fetal head)HypothermiaArrythmiasIdiopatic
51 DECELERATIONS Periodic changes in the FHR assume importance in defining the mechanism and intensity of asphyxia insults.There are 3 patterns of periodic decelerations based onthe configuration of the waveform and the timing of thedeceleration in relation to the uterine contraction.EARLY DECELERATIONSLATE DECELERATIONSVARIABLE DECELERATION
52 EARLY DECELERATIONS are not caused by systemic hypoxia do not appear to be associated with poor fetal outcomeoccur with fetal head compressionsbegin with the onset of uterine contractionsreach their lowest point at the peak of the contractionReturn to baseline as the contraction ends
54 LATE DECELERATIONS Occur in situations : - ablation of placentae maternal acute hypotensionhyper stimulation during oxitocin infusionacute decrease in the intervillous space flowAre found with increased frequency :preeclampsiahypertensiondiabetes mellitusintrauterine growth retardationother disorders associated with chronic placentalinsufficiency .
55 LATE DECELERATIONSusually are associated with acute/chronic fetoplacental insufficiencyoccur after the peak of the uterine contractionare precipitated by hypoxemia (which slows the FHR as results of CNS asphyxia) or direct myocardial depression and associated with mixed respiratory and metabolic acidosis
57 VARIABLE DECELERATIONS are inconsistent in configurationshave no uniform temporal relationship to the onsetof the contractionusually are the results of compressions of theumbilical cord between fetal parts and surroundingmaternal tissuesoften are associated with oligohydramnions (ex. PROM)may be associated with profound combined acidosis
63 In the presence of abnormal FHR patterns and uterine hypercontractility(not secondary to oxytocin infusion)tocolysis should be considered.A suggested regimen is subcutaneousterbutaline 0.25 mg.In cases of suspected or confirmed acutefetal compromise, delivery should beaccomplished as soon as possible, accountingfor the severity of the FHR abnormality andrelevant maternal factors. The accepted standardhas been that, ideally, this should be accomplishedwithin 30 minutes.
68 FETAL MOVEMENT COUNTSPerception of fetal movement is an inexpensive, noninvasivemethod of assessing fetal well-being.Generally, the patient is asked to relax on her left side 30minutes after eating and to concentrate on fetal movement.The patient should record the time that she starts the testand note each time the baby kicks or moves. A healthy fetusshould move approximately three to five times within onehour in this setting.
69 FETAL MOVEMENT COUNTSAn alternative method is the Cardiff Count-to-Ten chart,whereby the patient records fetal movements during thecourse of usual daily activity.A period of 12 hours without at least 10 perceivedmovements is considered a warning signal.If the test result is not reassuring, the patient should beevaluated and should undergo further testing, such asevaluation with a nonstress test.
70 FETAL MOVEMENT COUNTS Studies have shown that fetal movement counts are an effective screening measure,with reported reductions in fetal mortalityfrom 8.7 deaths per 1,000 live births to 2.1deaths per 1,000 live births.Although the ideal method for performing the test,including how often it should be repeated,has not been defined, it is clear that complaintsof decreased fetal movement are significant andwarrant further evaluation.
71 NONSTRESS TESTNonstress test is an indirect measurement of uteroplacentalfunction. The patient is usually seated in a reclining chair,slightly tilted to the left to avoid supine hypotension.A Doppler ultrasound transducer and a tokodynamometerare used to monitor the fetal heart rate and uterine activitysimultaneously. Fetal movements can also be recorded duringthe test.A reassuring, or reactive, nonstress test exhibits at least twoaccelerations in the fetal heart rate in a 20-minute period thatare at least 15 beats per minute above the baseline and lastat least 15 seconds.A nonreactive test does not meet these criteria.
72 NONSTRESS TESTFetal heart rate reactivity is a reflection of the balance between thefetus's sympathetic and parasympathetic tone. It is an acquiredneurologic reflex and is therefore dependent on gestational age:about 65 % of healthy fetuses will have a reactive nonstress test at28 weeks of gestation, 85 %t at 32 weeks of gestation and 95 % at34 weeks of gestation.Fetal heart rate accelerations are coupled to fetal movement as thefetus matures; consequently, they will be seen more frequentlywhen the fetus is awake or in an active sleep state. Since fetusescan have normal sleep cycles lasting up to 40 minutes, a nonstresstest might require over an hour to complete if it is initially nonreactive. It is important to differentiate whether a nonreactive tracing trulyrepresents a compromised fetus or merely reflects a temporarybehavioral state.
74 Doppler ultrasound in high risk pregnancies (Protocol for a Cochrane Systematic Review) Department of Obstetrics and Gynaecologyof the Center for Integral Attention to Women’s Health (CAISM)State University of Campinas (UNICAMP), Brazil
75 The first Doppler ultrasound report using continuous wave assessment of umbilical artery flow was published in 1977 (Fitzgerald 1977).With the use of colour Doppler, in 1987, it was possible to study the middlecerebral artery in fetuses and compare to umbilical artery pulsatility index (PI)ratio to demonstrate centralization of the fetal circulation (Wladimiroff 1987).Waveforms in the ductus venosus, was recognized as a key examinationto predict right heart failure in the hypoxic fetus and an important indicatorof imminent fetal demise (Kiserud 1991).The relationship between abnormal uterine artery Doppler velocimetry andpre-eclampsia, intra-uterine growth retardation and adverse pregnancyoutcome is well established (Aquilina 1996).
76 When the fetus is hypoxic, the cerebral arteries tend to become dilated in order to preserve the blood flowto the brain. In the middle cerebral artery, the systolicto diastolic (A/B) ratio will decrease (due to an increasein diastolic flow) in the presence of chronic hypoxic insultto the fetus. This increase in blood flow can be evidencedby Doppler ultrasound of the middle cerebral artery.This effect has been called "brain sparing effect" and isdemonstrated by a lower value of the pulsatility index.
77 UMBILICAL ARTERY DOPPLER VELOCIMETRY ... is based on the observation that flow velocity waveforms in the umbilical artery of normally growing fetuses differ from those of growth-restricted fetuses.Specifically, the umbilical flow velocity waveform of normally growing fetuses is characterized by high-velocity diastolic flow, whereas with intrauterine growthrestriction, there is diminution of umbilical artery diastolic flow. In some cases of extreme intrauterine growth restriction, flow is absent or even reversed.
93 Suspicious CTG Pathological CTG Inadequate quality CTG poor contact from externaltranducer?FSE not workingor detached?Uterine hypercontactilityIs the mather receiving oxytocin?Has the mother recently receivedvaginal prostaglandins?Maternal tachycardia/pyrexiamaternal infection?Tocolytic infusion?Dehydrated?Other maternal factorswhat is the maternal position ?Is the mother hypotensive?Has she just had a vaginal examination?Has she had a vasovagal episode?Has she just had an epidural?Stop oxytocin infusionconsider tocolysisIF T>38 consider screeningand treatementIf pulse >140/min. reduceTocolytic infusionCheck blood pressuregive crystalloid if appropriateCheck: maternal pulse,position of transducer,consider applying FSE.Suspicious CTGPathological CTGEncourage mother to adoptleft lateral positionCheck blood pressure give crystalloidif appropriate>7,25 FBS should be repeated if the FHR abnormality persists7,21-7,24 repeat FBS within 30 min. or consider delivery if rapidfall since last sample<7,20 Delivery indicated(all scalp pH estimations should be interpreted taking into theprevious pH measurment, the rate of progress in labour,clinical features of the mother and baby)Fetal blood samplingindicatedEncourage mother to adoptleft lateral positionCheck blood pressuregive crystalloidif appropriateFetal blood samplinginappropriateEncourage mother to adoptleft lateral positionCheck blood pressuregive crystalloidif appropriateExpeditedeliveryUrgency of delivery should take intoaccount the severity of the FHRabnormality and relevantinternal factors
94 CONTINUOUS ELECTRONIC FETAL MONITORING Are any of the following risk factors present?Maternal problems:previous cesarean sectionPre-eclampsiaPost-term pregnancy (>42weeks)Prolonged membrane rupture (>24hs)Induced labourDiabetesAntepartum haemorrhageOther maternal medical diseaseFetal problems:Fetal growth restrictionPrematurityOligohydramniosAbnormal Doppler artery velocimetryMultiple pregnancyMeconium-stained liquorBreech presentationIntremittent ausculationfor full minute after a contractionAbnormal FHR on ausculationBaseline <110bpm or > 160bpmAny decelerationsNoCardiotocograph classificationNORMAL A CTG where all four features fall into the reassuring categorySUSPICIOUS A CTG where features fall into one of the non-reassuringcategories and the remainder of the features are reassuringPATHOLOGICAL A CTG where features fall into two or more of theabnormal categoriesFetal heart rate feature classificationBaseline(bpm) variability(bpm) Deceleration AccelerationReassuring 5 none presentNon-reassuring <5 for40 early<90minutes variablesingle prolongedup to 3 minutesAbnormal <100 <5 for90 Atypical variable>180 minutes latesinusoidal single prolongedpattern for 10min. greater than 3 min.YesCONTINUOUS ELECTRONIC FETAL MONITORINGOffer and recommend continuous EFMThe absence ofaccelerations withan otherwisenormal CTGis of uncertainsignificanceIntrapartum risk factorsoxytocin augmentationepidural analgesiavaginal bleeding in labourmaternal pyrexiafresh meconium-stained liquorYesYes
95 PHYSIOLOGY OF LABOUR „ There are still those who think that the delivery of a woman is easy. ”François Mauriceau, 1694
101 ILIUM Iliac crest – provides attachments to the iliac fascia, abdominal muscles ,and fascia lata.Anterior superior and inferior spine – superior spineprovides the point of fixation of the inguinal ligamentPosterior superior and inferior spine – superior spine is thepoint of attachment for the sacrotuberous ligamentand the posterior sacral iliac ligament.Arcuate line – marks the pelvic brim and lies betweenthe first two segments of the sacrumIliopectineal eminence (linea terminalis) – the line of junctionof the ilium and the pubis.Iliac fossa – the smooth anterior concavity of the ilium,covered by the iliacus muscle.
102 ISCHIUM Ischial spine – delineates the greater and lesser sciatic notch above and below it. It is the point of fixationfor the sacrospinous ligament. The ischial spinerepresents an important landmark in the performanceof pudental nerve block and sacrospinous ligamentvaginal suspension; vaginal palpation during laborallows detection of progressive fetal descent.Ischial ramus – joins that of the pubis to encircle theobturator foramen; provides the attachment for theinferior fascia of the urogenital diaphragm and theperineal musculofascial attachments.
103 PUBIS Body – formed by the midline fusion of the superior and inferior pubic rami.Symphysis pubis – a fibrocartilaginous symphyseal jointwhere the bodies of the pubis meet in the midline ;allows for some resilience and flexibility, which iscritical during parturition.Superior and inferior pubis rami – join the ischial rami toencircle the obturator foramen. Provide the originfor the muscles of the thigh and leg. Provide theattachment for the inferior layer of the urogenitaldiaphragm.Pubic tubercle – a lateral projection from the superior pubicramus, to which the inguinal ligament, rectusabdominis, and pyramidalis attach.
104 PELVIC DIAMETERS 1- TRUE CONJUGATE DIAMETER 2- OBSTETRIC CONJUGATE ( 10,5 - 11,5 cm )2- OBSTETRIC CONJUGATE( cm )3- DIAGONAL CONJUGATE DIAMETER( 12,5 cm )123PELVIC DIAMETERS
105 For obstetrical purposes, the pelvis is described as having 3 imaginary planes Plane of the inlet: Four diameters have been described.Anteroposterior diameter: This is the distance between the sacral promontory and the symphysis pubis; it is designated the obstetrical conjugate. This conjugate normally measures approximately 10 cm or more, but it may be shortened considerably in an abnormal pelvis.Transverse diameter: This is the greatest distance between the linea terminalis on either side of the pelvis. This imaginary line usually intersects the obstetrical conjugate at a point approximately 4 cm in front of the promontory.Two oblique diameters: Each of these diameters extends from one of the sacroiliac joints to the iliopectineal eminence on the opposite side of the pelvis. These diameters normally average less than 13 cm each.
106 Plane of the mid pelvis: This is the plane of the smallest dimensions. This plane is extremelyimportant following engagement of the head inobstructed labor. The interspinous diameter(approximately >10 cm) usually is the smallestdiameter of the pelvis.
107 Plane of the pelvic outlet: This consists of 2 triangular areas created from the connection of an imaginary line between the 2 ischial tuberosities. The apex of the posterior triangle is at the tip of the sacrum, and the apex of the anterior triangle is under the pubic arch. The following 3 diameters of the outlet are of importance:Anteroposterior diameter: This normally is cm and extends from the lower margin of the symphysis pubis to the tip of the sacrum.Transverse diameter: This commonly is 11 cm and is the distance between the inner edges of the ischial tuberosities.Posterior sagittal diameter: This usually exceeds 7 cm and extends from the tip of the sacrum to a right-angle intersection with the line between the ischial tuberosities.
114 Pelvis of Mrs H extremely distorted by Mollities Ossium, a disease of adult life, which leads to softening of the bones of the body. Brim triangular - nearly closed on the left side. Successful Caesarean section performed, May 1849.
115 Transversely Contracted Pelvis. "Robert" pelvis. Note the faulty development of the sacral alae.The patient from whom this pelvis was removed was admittedto St. Mary's Hospital in June 1867 and delivered byCaesarean Section. Mother –died Child- lived
116 Small Round Pelvis. The pelvis of Mrs B, aged 27 years who died of rupture of the uterus as a result of dystocia,1st October, 1853.
117 Kyphotic or Funnel shaped Pelvis. The transverse diameters diminish from above downwards, being most contracted at the outlet.The conjugate of the outlet is also affected owing to the tiltingforwards of thelower end of the sacrum.
118 Model of female pelvis of Mrs M. distorted by a large exostosis springing from and intimately connected with the sarum.This large bony tumour occupied the cavity of this bone and alsothat of the coccyx. Caesarean section was performedSept 1829, Woman's age at time of birth 26.Duration of Labour –about 30 hoursMother - Died Child - Dead before operation.
120 „ The pelvis of Elizabeth Thompson is in the museum of St Mary's Hospital, Manchester, and was presented by me.There is a block of oak carved on the model which, with others, I havegiven to the aforesaid hospital. I have endeavoured to bring a mutilated infant through it, but I have never succeeded. However, it is one thing to operate on an inanimate machine, a block of wood, let it be ever so accurately formed, and another topo erate on the pelvis of a living woman. I deny the possibility of bringing a mutilated full-grown child through such a pelvis, whatever appliances are used."Thomas Radford
121 The passage of a babythrough a normal pelvisduring birth. The attempted passage ofa baby through an abnormalpelvis during birth.Note how natural birth wouldhave been impossible.
122 DIAMETERS OF THE FOETAL SKULL MENTO-OCCIPITAL (13.5cm)SUBOCCIPITO-BREGMATIC (9.5 cm)FRONTO-OCCIPITAL (12.0 cm)
123 LAMBOID S.POSTERIORFONTANELSAGITAL S.ANTERIORFONTANELCORONAL S.
124 STAGES IN THE MECHANISM OF LABOUR IN THE VERTEX PRESENTATION : Descent with engagement of the head andincreased flexionInternal rotationExtension, resulting in the birth of the headRestitution, or the untwisting of the neckExternal rotation of the head, accompanied with internal rotation of the shouldersDelivery of the shouldersExpulsion of the rest of the body of the foetus
125 DESCENT The movement of descent is brought about by two factors : General contents pressure of the uterusbefore rupture of the membranes Foetal axis pressure which comes intoeffect after the rupture of the membranes
126 DESCENT In normal cases the head engages in what is known as a synclitic manner :the sagittal suture of the head lies in oneor other of the oblique diameters of thepelvic brim, so that the parietal bones oneither side are at the same level.
127 DESCENT where abnormalities of mechanism occur, the sagittal suture may be pushed towardsthe symphysis pubis (posterior asynclitism =Litzmann’s obliquity)orthe sacral promontory (anterior asynclitism =Naegeli’s obliquity)
128 The fetal head descending through the pelvis in labour
129 The concept of the fetal head descending through the pelvis in labour is checked by vaginal examination when the levelof the presenting part is assessed against the level of the ischialspines (in centimetres) vertically
130 ENGAGEMENT OF FETAL HEAD A- maximum diameter of head is above inlet of pelvisand head is not engaged;B- engagement has taken place(maximum diameter of head is below inlet of pelvis);C- head is not engaged;D- when mother sits up on her elbows,the head sinks in,an indication that the head will engage when labour starts
131 INTERNAL ROTATIONThe shape of the pelvis : the forward incline ofthe walls of the pelvic cavity helps to rotateforwards the most dependent part of thepresenting pole.The tendency to forward rotation is helped bythe contour of the musculo-fascial forming thepelvic floor.
132 INTERNAL ROTATION The impetus given by the spine of the ischium is another dominant causativefactor in this phenomenon.The effective contractions of the uterusare essential to promote internal rotation.
133 EXTENTION is the resultant of forces : the effect of the uterine contractions from aboveand the elastic resistance of the pelvic floorfrom below
134 EXTENTION The occiput hitches against the symphysis pubis, the face sweeps over the perineum,and the successive parts of the foetal headto be born are the sinciput.
135 RESTITUTION As soon as the head is free outside the vulval outlet it rotates through 1/8 of a circle, andthus the neck is untwisted and the chin rotatestowards the right (left occipito-ant. position) orthe left (right occipito-ant. position)
136 EXTERNAL ROTATION After the untwisting of the neck has occurred, the next movement is one of internal rotationof the shoulders. This brings the anteriorshoulder underneath the symphysis pubis,and with this movement occurs externalrotation of the head:the bisacromial diameter is broughtinto the antero-posterior diameter ofthe pelvic outlet.
137 EXTERNAL ROTATION Once the shoulders have rotated into the antero-posterior diameter of the outlet, descent continues with the uterine contractions, until the anterior shoulder hitches underneath the symphysis pubis and the posterior shoulder sweeps over the perineum by a process of latero flexion of the spine and is delivered first.
138 VAGINAL EXAMINATION IN LABOUR 1. Condition of the vulva, the vagina: theextent to which they are dilatable and thepressure of any lubricating mucus.2. The condition of the cervix: whether thecervical canal is dilated and the extend towhich the external os is dilated or dilatable.3. The condition of the bladder and rectum
139 VAGINAL EXAMINATION IN LABOUR 4. Whether the membranes are entire or ruptured.If present, the nature of the bag and whetherthe membranes are tough.5. The presenting part - whether it is the heador any other part of foetus, and the particulardetails concerning the presenting part.6. The presence of a caput and the degree ofmoulding in cephalic presentations.
140 VAGINAL EXAMINATION IN LABOUR 7. The exact position of the presenting partwith reference to the maternal pelvis iswhether the head is at the brim, or throughthe inlet in the cavity, or at the outlet.8. Whether in cases of cephalic presentationthe occiput has rotated, and if so, to whatextent.
141 VAGINAL EXAMINATION IN LABOUR 9. Whether the sacral promontory can bepalpated or not.10. The presence of abnormalities, such aprolapsed cord, or placenta praevia.
142 WHEN SHOULD THE MEMBRANES BE RUPTURED ARTFICIALLY? When the cervix is fully dilated andthe bag of waters remains entire owingto tough membranes.In some cases of antepartum haemorrhage,rupturing the membranes controls bleeding.
143 WHEN SHOULD THE MEMBRANES BE RUPTURED ARTFICIALLY? As a method of induction of labourAs a preliminary to operative delivery
144 STAGES OF LABOUR II - the stage of expulsion I - the stage of dilatationII - the stage of expulsionIII - the stage of placental deliveryand uterine contractionand retraction
145 THE FIRST STAGE True uterine contractions, or labour pains A muco-sanguinous discharge or the „show”The dilatation of the cervical canal, so thatboth the internal and the external os becomecompletely dilatedThe fixation of the head at the brim of thepelvis and its progressive descentRupture of membranes
146 Latent (a) and active (b) phase of labour in a multiparous and a primiparous woman, as shown on partogram
147 Information conveyed on a partogram Fetal heart rate by intermittent auscultation orcontinuous fetal heart rate monitoringCervicogram a record of cervical dilatation and fetalhead descentUterine contractions quantification of frequency,strength, and durationAmniotic fluid (if the membranes are ruptured) stateof fluid, any meconiumMaternal urine production checked for ketones andproteinDrugs given analgesics, oxytocicsMaternal blood pressure, pulse, and temperature
148 THE SECOND STAGEThe occurrence of the characteristic uterine contractionsThe coming into action of the accessory muscles of labourThe progressive descent of the presenting partThe dilatation of the vagina and vulva with stretching of the pelvic floorThe expulsion of the foetus
149 When the cervix has dilated to 10 cm, the mother has an uncontrollable urge to push
153 THE CAUSES OF PERINEAL LACERATIONS ARE : Relative disproportion in size between the presenting part and the vaginal outlet.Too rapid expulsion of the presenting part, so that enough time is not allowed for gradual stretching of the perineumFaulty mechanism, whereby a larger diameter of the presenting part emerges through the outlet
154 THE THIRD STAGEThe separation of the placenta after the formation of a retroplacental haematomaThe expulsion of the placentaThe control of the haemorrhageThe permanent contraction and retraction of the uterus
155 A P G R Activity; muscle tone Pulse rate Grimace; reflex irritability The Apgar test is a scoring system designed by Dr. VirginiaApgar, to evaluate the condition of the newborn at one minuteand five minutes after birth.AActivity; muscle tonePPulse rateGGrimace; reflex irritabilityAppearance; skin colorRRespiration
156 THE CAESAREAN SECTIONHorizontal incision Vertical incision
166 FORCEPS 1 cm 9,5 cm 4 cm 9 cm 40,5cm 15cm Naegele type Franz Karl Naegele
167 Indications for operative vaginal deliveries are identical for forceps and vacuum extractors. The following indicationsapply when no contraindications exist:Prolonged second stage: (1) This includes nulliparous woman with failure to descend for 2 hours without, and 3 hours with, conduction anesthesia. (2) multiparous woman with failure to descend for 1 hour without, and 2 hours with, conduction anesthesia.Suspicion of immediate or potential fetal compromise is an indication.Shortening of the second stage for maternal benefits: Maternal indications include, but are not limited to, exhaustion, bleeding, cardiac or pulmonary disease, and history of spontaneous pneumothorax.In expert hands, fetal malpositions, including the after-coming head in breech vaginal delivery, can be indications for forceps delivery.
168 Prerequisites for forceps delivery include the following: The head must be engaged.The cervix must be fully dilated and retracted.The position of the head must be known.The type of pelvis should be known.The membranes must be ruptured.No disproportion should be suspected between the size ofthe head and the size of the pelvic inlet and mid pelvis.The patient must have adequate anesthesia.Adequate facilities and supportive elements should beavailable.The operator should be fully competent in the use of theinstruments and the recognition and management ofpotential complications.An operator should be present who knows when to stop, tonot force the issue, and to not aggressively use both forcepsand vacuum in combination because this has been shown toincrease morbidity for both the mother and fetus.
177 Forceps deliveryDisarticulation of the branches of the forceps; beginning modified Ritgen maneuver
178 Contraindications to forceps-assisted vaginal deliveries:Any contraindication to vaginal delivery .Refusal of the patient to consent to the procedureCervix not fully dilated or retractedInability to determine the presentation and fetalhead position or pelvic adequacySuspected cephalopelvic disproportionUnsuccessful trial of vacuum extractionAbsence of adequate anesthesiaInadequate facilities and support staffInexperienced operator
179 forceps-assisted vaginal deliveries: Maternal complications associated withforceps-assisted vaginal deliveries:Early (ie, acute) complications include (1) lacerations to the cervix, vagina, perineum, or bladder; (2) extension of episiotomies; (3) increase in blood loss; (4) hematomas;and (5) intrapartum rupture of the unscarred uterus.Late complications mainly are related to injury to the pelvic support tissues and organs and include (1) urinary stress incontinence, (2) fecal incontinence, (3), anal sphincter injuries, and (4) pelvic organ prolapse.
180 Fetal complications associated with forceps-assisted vaginal deliveries:Transient facial forceps marks, bruising,lacerations, and cephalohematomas are possible.Skull fractures, intracranial hemorrhage with falx,or tentorial lacerations also have been reported.Cerebral palsy, mental retardation, and behavioralproblems tend to be more related to hypoxic episodesor other intrapartum, environmental, or congenitalfactors.
181 FORCEPS AND VACUUM EXTRACTION CONDITIONS :Cervix - fully dilatedMembranes - rupturedPosition and station of fetal head –known and engagedFetus - aliveMaternal pelvis - evaluated and foundappropriate
182 FORCEPS AND VACUUM EXTRACTION INDICATIONS :Delay in the second stage of labourProphylaxis (to shorten the second stage of labour)Fetal distressMaternal distress
183 FORCEPS INJURIES BABY : MOTHER : Intracranial haemorrhage Shoulder dystociaFractures of the skullParesis of the facial nerveMOTHER :Tears of the cervix and vaginaUterine ruptureDamage of the bladder and rectumInfection
184 VACUUM INJURIES BABY : MOTHER : Abrasion to the scalp Cephalhaematoma Retinal haemorrhageMOTHER :Local injuries are significantly lesscommon then with forceps
186 VARIETIES OF BREECH PRESENTATION - Breech with extended legs- Complete breech- Footling
187 BREECH PRESENTATION- DIAGNOSIS PRESENTING PART- the head is round, hard and regular. The breech is small, softer and irregular.EXTERNAL EXAMINATION- the head in the fundus is ballotable (first Leopold maneuver).FETAL HEART is detected higher in the abdomen (above the umbilicus).
188 BREECH PRESENTATION- PROGNOSIS Perinatal mortality is 5 times that of the cephalic presentation !REASONS :HypoxiaDifficulty with delivery of the aftercoming headBirth trauma
189 BREECH PRESENTATION- MANAGEMENT What is the correct treatment ?Caesarean sectionExternal versionElective breech delivery?
190 EXTERNAL (CEPHALIC) VERSION PROFITSReduction of caesarean sectionsRISKPlacental separationPremature rupture of the membranesPremature labourEntanglement of the cordFetomaternal red cell transferFetal trauma
191 EXTERNAL (CEPHALIC) VERSION CONDITIONSRelax uterus and abdominal wallBreech mobile above brimComplete breechMultiparityThe fetal heart should be monitoredCONTRAINDICATIONSCaesarean section is to be carried out (the breech is easier then the head to deliver via a uterine incision)Antepartum bleedingMultiple pregnancyRuptured membranesOligo- and ahydramnionFetal death
192 THE SUGGESTED CRITERIA FOR A VAGINAL BREECH DELIVERY Normal labour curveEstimated fetal weight between gComplete breech presentationA reassuring fetal heart trackingAn adequate maternal pelvis by clinical pelvimetryNormally flexed fetal head
193 TRANSVERSE LIE AETIOLOGY Uterine malformations (bicornuate, subseptate uterus)PolyhydramnionPraevial attachment of the placentaMultiparityTumours of the uterusMultiple pregnancy
194 TRANSVERSE LIE DIAGNOSIS Ultrasound ! Contour of the abdomen - lateral expansionNo fetal pole in the fundus or lower uterusVaginal examination- very carefully !Possibility of placenta praevia and possibility of rupturing of membranes accidentally.
195 TRANSVERSE LIE - MANAGEMENT OF LABOUR AND DELIVERY Caesarean section - the procedure of choiceInternal version followed by breech extraction - associated with a high fetal mortality rate and the risk of uterine ruptureThere is no normal mechanism of labour. Only small babies may occasionally be delivered by spontaneous evolution
196 DEFLEXION ATTITUDES OF THE FETUS BREGMA PRESENTATION(military attitude , “Eyes front” attitude)DIAGNOSISanterior frontanelle (bregma) will be felt first, the smaller posterior frontanelle will be difficult to reach or out of touchDiameter of the fetal skull - Occipitofrontal (11-12 cm)Leading point - vertex (bregma)The prognosis for vaginal delivery is poor. Nowadays, caesarean section would be preferred to manual flexion followed by forceps delivery
197 DEFLEXION ATTITUDES OF THE FETUS BROW PRESENTATIONDIAGNOSISPalpation of the fetal trunk - the chest is pushed forward and may be on the opposite side to the breech. The fetal heart is often heard easily over the prominent chestVaginal examination - central forehead will be felt, with the frontal suture running across it.Diameter of the fetal skull - mentovertical (14 cm)Leading point - brow (sinciput)Vaginal delivery is very difficult. Nowadays Caesarean section is the preferred manoeuvre (procedure of choice)
198 DEFLEXION ATTITUDES OF THE FETUS FACE PRESENTATIONis the most extreme form of deflexionDIAGNOSISExternal examination - the deep groove between fetalbeck and occiputThe fetal heart is heart easily over the prominent chestVaginal examination - partly soft, partly firm, irregular contour will be noted (compare with breech, anencephalus)Diameter of the fetal skull - submentobregmatic(9,5 cm - the same as the most favourable when thehead is fully flexed – suboccipito-bregmatic)Leading point - face (root of the nose)