Bukovinian State Medical University
“Approved”
on methodological meeting
of Department of Obstetrics and Gynecology
with course of Infant and Adolescent Gynecology
“___”______200_ year
protocol #
The Head of the department
Assistant Professor
______S.P.Poliova
Methodological instruction
for practical lesson
“Breech presentation. Malpresentations. Contracted pelvis”
Module 1: Physiology of pregnancy, labor and puerperium
Context module 2: Perinatology. Risk factors of perinatal period.
Subject: Obstetrics and Gynecology
4th year of studying
2nd medical faculty
Number of academic hours – 4
Methodological instruction developed by:
assistant Andriy Berbets
Chernivtsi – 2008
Aim: to learn the biomechanism of labor in breech presentation, recognise the breech presentation and be able to render the manual assistants in labor in the different types of breech presentation. To learn how to make the diagnosis of malpresentations. To show the causes which results in this. To learn the indications, conditions and the techniques for operation of obstetric versions.
Professional motivation: The breech presentations occur in about 3-4% of all labors. With breech presentation, compared to cephalic presentation both the mother and the fetus are at greater risk. The prognosis for the fetus in a breech presentation is considerably worse than when in a vertex presentation. The operative delivery rate is higher and may be; higher maternal morbidity and mortality. It is very important to know the biomechanism of labor in breech presentation and the correct management-1 of labor. Students have to be able to render the manual aid to avoid the complication coursed by pathological labor.
Malpresentations are very actual obstetrics problem because it results in increasing of maternal and fetal morbidity and mortality. It is also impossible to manage labors through maternal passages and needs using of obstetrics operation, in most cases cesarean section.
Contracted pelvis: learning the main types and peculiarities of labor in contracted pelvis gives a possibility to prevent the main obstetric complications, perinatal and maternal death.
Basic level:
BREECH PRESENTATION
1. Anatomy of fetal head.
2. Anatomy and topography of the uterus, pelvis and pelvic floor.
3. External and internal examination of pregnant women.
4. The structure of the fetal head.
5. Diameters of the fetal body at term.
6. The stages of the labor.
MALPRESENTATIONS
1. Anatomy and topography of the uterus
2. External and internal examination of pregnant women
3. Methods of diagnostic of different fetal positions.
4. Measuring of external pelvis sizes.
5. Kinds of obstetrics operations, indications and contraindincations for cesarean section, craniotomy and embriotomy
6. The preoperative preparing of patients. The deflexed vertex presentation — diagnosis, the cardinal movements of labor, prognosis, the management of labor.
7. The brow presentation — diagnosis, the cardinal movements of labor prognosis, the management of labor.
8. The face presentation - diagnosis, the cardinal movements of labor, prognosis, the management of labor.
9. Prognosis and complications of the labor in deflexed presentation.
10. The deforms of the fetal head in deflexed presentation.
11. The methods of operative delivery in deflexed presentation.
CONTRACTED PELVIS
1. Etiology and pathogenesis of abnormal development of pelvis.
2. Sizes of normal pelvis.
3. Principles of dispensary monitoring for the pregnant women with
contracted pelvis.
4. Methods of pregnant and puerpera investigation.
5. Estimation of external and internal pelvic sizes.
6. Clinic and management of physiologic pregnancy and labor.
7. Cardinal moments of labor in flexed and deflexed vertex presentations.
STUDENTS' INDEPENDENT STUDY PROGRAM
I. Objectives for Students' Independent Studies
You should prepare for the practical class using the existing textbooks and lectures. Special attention should be paid to the following:
BREECH PRESENTATION
1. Classification of breech presentations.
2. Diagnosis of breech presentations.
3. The biomechanism of the labor in breech presentations.
4. The cardinal movements of labor in breech presentations.
5. The manual aid by Tsovyanov I on the labor in the frank bree< presentation.
6. The classic manual aid on the labor in the complete and incomplete, breech presentation.
7. The manual aid by Tsovyanov II on the labor in the footling breech presentation.
8. The operativedelivery in the breech presentation.
9. The complications to the delivery in a breech presentation.
MALPRESENTATIONS
1. The determination of malpresentations.
2. Types oi malpresentations.
3. The making diagnosis of malpresentations, physical and instrumental
methods of investigations.
4. The determination of obstetrics version. Classification.
5. The indications for external obstetrics version.
6. The contraindications and conditions for the operation of extern*
obstetrics version.
7. The indications, contraindications and requirements for the poda"
internal obstetric version.
8. The technique for the operation of the external obstetrics versio
9. The technique for the operation of the internal podalic version
10. Anesthesia for the operations.
1l. The complications caused by obstetrics versions.
12. Management of postoperative period.
CONTRACTED PELVIS
1. Pelvic classification according to form of contractions.
2. Anatomically and clinically contracted pelvis.
3. Diagnosis of contracted pelvis.
4. Pelvic classification according to degree of contraction.
5. Often occurred contracted pelvis: generally contracted pelvis, sial pelvis: simple flat pelvis, flat rachitic pelvis, generally contracted flat pelvis
6. Principles of pregnancy management in contracted pelvis.
7. Principles of labor management in contracted pelvis.
8. Cardinal moments of labor in different types of contracted pelvis-
9. Vasten's and Zangemeister sign.
Key words and phrases: biomechanism, breech presentation, frank
breech presentation, complete and uncompleted breech presentation, descent, flexion, rotation, extension, the manual assistance by Tsovyanov I and by Tsovyanov II, the classic manual assistance, transverse lie, oblique lie, long axis of the fetus, unstable lie, obstetrics versions.
Summary
BREECH PRESENTATION
There is a fundamental difference between delivery in cephalic and breech presentation. With a cephalic presentation, once the head is delivered, typically the rest of the body follows without difficulty. With a breech, however, successively larger or, in case of the head, very much less compressible parts of the fetus are born.
Spontaneous complete expulsion of the fetus that presents as a breech, as described below, is seldom successfully accomplished. As the rule, either cesarean section of vaginal delivery that requires skilled participation by the obstetrician is essential for a favorable outcome.
Etiology. Breeches are much more common at the end of the second trimester of pregnancy than at or near term. Factors other than prematurity that arrear to predispose to breech presentation include uterine relaxation association with great parity,multiple fetuses,hydramnion.hydrocephalus, anencephalus, previous breech delivery, uterine anomalies, and tumors.
Classification. The varying relations between the lower extremities and buttocks of the fetus in breech presentation form the categories of frank breech, complete breech, incomplete breech presentation, footling and kneeling presentation.
In frank breech presentation the lower extremities are flexed at the hips and extended at the knees and thus the feet lie in close proximity to the head.
In complete breech presentation the lower extremities are flexed at hips and at the knees.
In incomplete breech presentation the lower extremities are flexed at nips and at the knees and the one or both feet lie below the breech. »n footling presentation the feet lies lower than breech. 1 tie kneeling presentation is the especial form of the breech, when the fetal knees are lower than the breech.
Diagnosis. The diagnosis of the breech presentation may be making 'he help of external and internal obstetrics investigation. With the first maneuver of the external examination we identify the hard, round ballottable fetal head to occupy he fundus of the uterus. The second maneuver indicates the back to be on one side of the abdomen and the small parts in other. On the third maneuver the breech is movable above the pelvic inlet. The heart sounds of the fetus are usually heard loudest slightly above the umbilicus.
Vaginal examination. In frank breech presentation only buttocks and its characteristics components (both ischial tuberosities, the sacrum, the anus, the external genitalia) are usually palpable. In incomplete breech presentation the buttocks and the feet may be palpated. In footling the fetal feet are lower than buttocks.
Biomechanism of labor in breech presentation,
I moment - the internal breech rotation. The breech rotates and fetal intertrochanteric diameter from one of oblique size of the pelvic inlet to anteteroposterior size of the pelvic outlet.
II moment - the lateral flexion of the body. The anterior hip is stemmed against the pubic arc. By lateral flexion of the fetal body the posterior hip is forced over the anterior margin of the perineum. Then anterior hip is born.
III moment - the internal shoulders rotation. Alter the birth of the breech, there is the slight external rotation as a result of the descends and rotations of the shoulders. The shoulders rotates on the pelvic floor and. diameter biacromialis occupies anteroposterior diameter of the pelvic outlet.
IV moment - the lateral flexion the body in the thoraco-brachial part. The shoulders are born.
V moment - the internal rotation of the head. The rotation begins when the fetal head descends from the plane of greatest pelvic dimensions, to the least pelvic dimensions (midpelvis). The rotation is complete when the head reaches the pelvic floor, the sagittal suture is in the anteroposterior diameter of the pelvic outlet and the small fontanel is under the symphysis
VI moment - the flexion of the fetal head. The head fixes with its, fossa suboccipitalis to the inferior margin of symphysis pubis and flexes. The face,forehead,vertex,and occiput are born.
The manual aids in breech presentations.
The manual aid by Tsovyanov I in frank breech presentations.
The aim of the manual aid: to prepare the maternal ways to the delivery of the head and shoulders and to keep the normal attitude of the fetus.
in the frank breech presentation the fetus extremities are flexed the hips and extended at the knees and thus the feet lie in close proximity to the head. The circumference of the thorax with the crossing on it arms so their circumference is larger than circumference of the head and the after-coming; which deliveries easily.
The technique. The aid begins after the delivery of the buttocks. Thephysician’s hands are applied over the buttocks, the thumbs placed on fetus sacrum and other fingers on the legs. The doctor gently supports legs to avoid its flexion. If the normal attitude of the fetus is keeping head deliveries easy.
The classic manual aid on the labor in complete and incomplete breech presentation.
The aim of the classic manual aid: to help of the shoulders and the head delivery.
The classic manual aid begins when the lower angular of the anterior scapula became visible. There are 4 moments of the classic manual aid.
I moment - the delivery of the posterior arm. The posterior shoulder must be delivered first. The feet are grasped in one hand and drawn upward over the groin of the mother toward which the ventral surface of the fetus is directed; in this manner, leverage is exerted upon the posterior shoulder, which slides out over the perineal margin, usually followed by the arm and hand.
II .and III moment - the external trunk rotation and removal of the posterior arm The aim of this moment is the reverse of the anterior shoulder to the sacrum and the delivery of second arm. The obstetrician applies his hand on the lateral sides of the fetus trunk and rotates it. The direction of the movement must be in this way: the occiput must go under the symphysis pubis. When the posterior shoulder and arm appears at the vulva the doctor put two fingers into the vagina, the fingers passed along the humorous until the elbow is reached. The fingers are now used to splint the arm, which is swept downward and delivered through the vulva.
IV moment - delivery of the head. After the shoulder' are born, th head usually occupies an oblique diameter of the pelvic with the occiput directed anteriorly. The fetal head may then be extracted by the method of Mauriceau-Levret. Employing the Mauriceau-Levre maneuver to help flex head, the doctor's middle finger of one hand are applied into the fetal mouth, while the fetal body rests upon the palm of the hand and fore arm, which is straddled the fetal legs. Two fingers of the operator's other hand are then hooked over the fetal neck and grasping the shoulders, downward
traction is applied until the suboccipital region appears under the symphysis.
The body of the fetus is then elevated toward the mother abdomen, and mouth, nose, brow and the occiput emerge over the perineum. Gentle traction should be exerted by the fingers over the shoulders.
The manual aid by Tsovyanov II in footling presentation
The aim of the manual aid: To perform the footling presentation the incomplete breech and to prepare the maternal ways to the deliver the head and shoulders.
The doctor covers the area of the vulva with the sterile napkin and puts up resistance to the delivery of the feet. The feet are flexing and the footling presentation becomes incomplete breech presentation. Than the delivery manage as in incomplete breech presentation.
Favorable factors for breech delivery:
1. Gestation age of more than 36 but less than 38 weeks. If the baby small, the head will be lager than the breech and may be trapped i cervix; if too large, the difficulty is obvious.
2. Estimated fetal weight of more than 2500 but less than 3175g
3. The presenting part at or below station -1 at the onset of labor
4. The cervix soft, effaced, and dilated more than 3 cm.
5. Ample gynecoid or anthropoid pelvis (the head will enter th pelvis in the anterior position).
6. A history of a previous breech delivery of a baby weighing more than 3175g or a previous vertex delivery of baby weighing more than 3600g.
Unfavorable factors:
1. Gestation age of more than 38 weeks.
2. Estimated fetal weight of more than 3500 - 3600g.
3. The presenting part is at pelvic inlet.
4- The cervix firm, incompletely effaced, and less than 3 cm dilated
5. No history of prior vaginal delivery, or history of difficult vaginal delivery
6. Android or flat pelvis.
7. Footling or full breech presentations.
8. Extension of the fetus head is extremely unfavorable and is indication for cesarean section.
The presence of any one of the aforementioned unfavorable factors should strongly suggest the desirability of delivery by cesarean. section.
The predelivery examination: its chief purpose is to confirm the conditions for the operation.
Indications for breech extraction:
• The requirement for instant vaginal delivery;
• Cases in which one is already committed to vaginal delivery and cesarean section is not appropriate or feasible (maternal indications -preeclarnpsia, hard heart and puimonal diseases, cord prolapse; fetus indications - acute hypoxia);
• The breech extraction is committed after the operation.
The conditions for breech extraction:
• The cervix must be completely dilated and retracted high in the pelvis (although the breech - especially in footling presentation - may pass the cervix without incident, the shoulders or head will surely be trapped by incompletely dilated cervix);
• The uterus must be relaxed;
• The normal fetopelvic proportion;
• The rupture of membranes.
The techniques for breech extraction.
The techniques for the operation of extraction fetus on the two legs.
Dy\uring total breech extraction, the obstetrician's entire hand should be inserted through the vagina and both feet of the fetus grasped. The breech are held with the second finger lying between them. The feet are brought down the vagina, and gentle traction applied until they appear from the vulva. Now both feet are grasped and pulled through the vulva. As the legs commence to emerge through the vulva, they should be wrapped in sterile towel to obtain a firmer grasp, for the vernix caseosa renders them difficult to hold. Downward gentle traction is then continued.
As the legs emerge, successively higher portion are grasped, first the legs (shins) and later the thighs. When the breech appears at the vulva, gentle traction is applied until the hips are delivered. As the buttocks emerge, the hack of the infant usually rotates to the anterior. The thumbs of the operator are then placed over the sacrum and gentle downward traction is continued until the costal margins, and then, the scapulas become visible. The back of the infant tends to turn spontaneously toward the side of the mother to which it originally directed. If turning does not occur, slight rotation should he added to the traction, with the object of bringing the bisacrorrsial diameter of the fetus in the antero-posterior diameter of the pelvic outlet.
There are two methods of delivery of the shoulders: with the scapulas visible, the trunk is rotated in such a way that the anterior shoulder and the arm appear at the vulva and can easily be released and delivered first. The operator is shown rotating the trunk of the fetus counterclockwise to deliver
the right shoulder and arm. The body of the fetus is then rotated in the reverse direction to deliver the other shoulder and arm. If trunk rotation is unsuccessful, the posterior shoulder must be delivered first. The feet are grasped in one hand and drawn upward over the groin of the mother
toward which the ventral surface of the fetus is directed; in this manner, leverage is exerted upon the posterior shoulder, which slides out over the perineal margin, usually followed by the arm and hand. Then, by depressing the body of the fetus, the anterior shoulders emerges beneath the pubic arch, the arm and hand usually follow spontaneously. Thereafter, the back ends to rotate spontaneously in the direction of the mother's symphysis. If upward rotation fails to occur, it is effected by manual rotation of the body.