Persistent occipital posterior dystocia

Introduction to persistent post-occipital dystocia The persistent occipitoposterior is due to the connection of the fetal head to the posterior occipital position during childbirth. During the descending process, when the fetal head double top diameter reaches or approaches the middle pelvic plane, most of the internal rotation can be completed. Natural birth in the front of the pillow. 5% to 10% until the end of childbirth, the occipital portion of the fetal head can not continue to turn to the front, still behind the mother's pelvis. basic knowledge The proportion of illness: 0.04% Susceptible people: good for women Mode of infection: non-infectious complication:

Persistent post-occipital dystocia

(1) Causes of the disease

The reason for the occurrence of persistent posterior occipital position is not very clear, but in terms of the relationship between the three factors of birth canal, fetus and productivity, the formation of persistent posterior occipital position is not determined by a single factor, often It is the result of mutual influence and mutual restraint of various factors. The main influencing factors are as follows:

1. Abnormal pelvic morphology and size are important causes of posterior occipital position, especially male and sacral pelvis. The pelvic inlet is narrow in the front half, the back half is wide, and the occiput is wider. It is easy to take the occipital position. The pelvis is narrow, which makes it difficult for the fetal head to enter the basin. The second hospital of Chongqing Medical University determines the fetal position by ultrasound imaging. After observing the posterior position of the pillow, it is found that there is a male pelvis. The characteristics accounted for 26.24%, while the anterior occipital position had no male pelvic characteristics; the posterior occipital group had 35.29% of different degrees of pelvic stenosis, and only 1 case of pelvic stenosis was 6.3%.

2. The size of the head basin does not impede the rotation of the fetal head. According to the comparison of 258 cases of persistent posterior occipital position and 250 cases of anterior occipital delivery in the Second Affiliated Hospital of Chongqing Medical University, according to the head basin score, the persistent post-occipital position score is 7 The scores of 7 points or less (head basin not mentioned) accounted for 39.14%, and the anterior occipital position was only 18%. The incidence of headless basins in the persistent posterior occipital group was significantly higher than that of the anterior occipital group.

3. The poor fetal head flexion causes the fetal head to increase through the birth canal line. The diameter of the fetal head through the pelvis and the size of the pelvis are not known, which makes it difficult to rotate and descend the inner end of the fetal head, so that the fetal head continues behind the pillow. Position, the anterior position of the occipital, the fetal head flexion is good, with the anterior occipital diameter (9.5cm) through the birth canal; the posterior occipital head is poorly flexed, even without flexion, may be the pillow diameter (1l.3cm Through the birth canal, the fetal head diameter is increased by 1.8cm. If the fetal head reaches the pelvic floor with the occipital posterior position, the fetal head not only does not bend, but also slightly stretches, Greenhill calls it the goose neck, meaning Describe the extension of the fetal head in the posterior position, the first sputum is exposed first, in this case the increase of the fetal head diameter is >1.8cm, therefore, the resistance of the fetal head through the birth canal is greater than the resistance of the anterior Much, this is not conducive to the joint and rotation of the fetal head, and is not conducive to the fall of the fetal head.

4. Sustained occipital posterior position and uterine insufficiency form a causal relationship. The rotation and descending of the fetal head require uterine contraction force to complete. If the productivity is insufficient, it is difficult to promote the rotation of the fetal head, but from the Second Affiliated Hospital of Chongqing Medical University. According to clinical data, only 12.97% of the 258 persistent occipital posterior cases showed primary uterine atony, 31.8% of secondary uterine atony due to obstruction of labor, and abnormal productivity did not lead to persistence. An important reason for the posterior position of the pillow, however, once the productivity is abnormal, it is more difficult to overcome the posterior position of the pillow. Therefore, the weakness of the uterine contraction is often the consequence of abnormal fetal position.

(two) pathogenesis

In the case of no head basin and normal productivity, most of the posterior occipital position and occipital transverse position can be converted into anterior occipital natural delivery. If it can not be converted into anterior occipital position, the delivery mechanism has the following conditions:

1. The posterior occipital posterior occipital posterior posterior occipital posterior occipital posterior occipital occipital posterior occipital posterior occipital sulcus There are two types of delivery methods:

(1) The fetal head flexes better: the fetal head continues to fall, and when the anterior iliac crest reaches the pubic symphysis, the sputum is used as the fulcrum, and the fetal head continues to flex, so that the top and the occipital part are delivered from the perineal anterior border, and then the fetal head is raised. Stretching, forehead, nose, mouth, and sputum are successively delivered by the pubic symphysis (Fig. 1). This method is the most common way of delivering vaginal midwifery after delivery. It is more common in women with strong productivity, small fetus and large pelvis. .

(2) bad fetal head flexion: the fetal front is exposed under the pubic symphysis, gradually the nasal root is delivered, the nasal root is used as the fulcrum, the fetal head is flexed, and the front sac, the top and the occipital are successively delivered from the perineal front. The fetal head is stretched out, and the nose, mouth, and ankle are delivered from the pubic symphysis. At this point, all the fetal heads are delivered. Because the fetal head rotates with a larger circumference of the pillow, the fetus is delivered more difficult than the previous one, and more surgery is needed.

2. Childbirth machine transfer and delivery mode The fetal head is placed in the basin after the pillow is taken, which cannot be determined as abnormal machine rotation, because most of the fetal heads can be turned forward 135° to the front of the pillow, and the front position of the pillow is used to complete the delivery. If the back position of the pillow cannot be rotated 135° forward, the following three situations can occur:

1 fetal head in each plane of the pelvis lasts in the right rear position of the pillow or the left rear position of the pillow. If the fetal head is not connected, or stays above +2 or +2, the artificial rotation fails, the possibility of vaginal delivery is small, and more cesarean section is needed. End the birth,

2 The fetal head rotates 45° backwards, so that the sagittal suture is consistent with the anterior and posterior diameter of the pelvis, and descends to the pelvic floor with a low straight position. The occipital bone is in front of the humerus, and the anterior humerus is under the pubic arch. The fetal head is well bent. The fulcrum, the top, the occipital part is delivered from the perineal anterior border, and then the fetal head is stretched and stretched, and can be delivered naturally through the vagina; if the fetal head is poorly bent, the forehead of the fetus is first exposed under the pubic symphysis, and the nasal root is gradually delivered to the nose. The root is the fulcrum, the fetal head is flexed, the anterior iliac crest, the head and the occipital part are delivered, and the fetal head is stretched again. The nose, mouth, and sputum are finally delivered, and the final fetal head is delivered (Fig. 3). This is more common in productivity. A fetus with a small fetus and a large pelvis can be delivered naturally through the vagina; if the fetal head is poorly bent, the forehead of the fetus is first exposed under the pubic symphysis, and the base of the nose is gradually delivered, with the base of the nose as the fulcrum, the fetal head is flexed, and before delivery., the top of the head and the occipital part, the fetal head stretches again, continue to deliver the nose, mouth, sputum, and finally the whole fetal head is delivered. This method of delivery is more difficult than the former, and the forceps must be used to assist the delivery, but the fetal head suction device is prohibited. ,

3 The fetal head rotates 45o forward to the bottom of the pelvis to form a low transverse position of the fetal head, and delivers in a continuous occipital position.

Because the scholars have different positive and conservative attitudes towards the posterior position of the pillow, as well as the pelvic morphology of women in different races and regions, the delivery and delivery methods of the postpartum position are not the same. The second affiliated to Chongqing Medical University Ultrasound imaging was used to detect the fetal head position. Hou Jingrong observed 34 cases (53.13%) of the anterior occipital vaginal delivery through the observation of 64 cases of post-occipital delivery. The progress of delivery and the way of delivery and the front of the pillow were observed. Similar in position, the labor process is longer than the anterior position of the pillow, and the rotation of the fetal head occurs more frequently when the fetal head reaches +1, +2, +3 or dialing, and 19 cases continue to produce in the posterior position after the full trial production (29.69%) ), the period of labor was significantly longer than the internal rotation success, vaginal assisted rate and cesarean section rate also increased significantly, 7 cases accounted for 10.94% of the fetal head turned to the posterior position; 4 cases accounted for 6.25% of the occipital position Some people studied the progress of childbirth after the left side of the pillow and the right side of the pillow. It was found that the left side of the pillow was shorter than the right side of the pillow and the child was born. The analysis showed that there was no significant difference in the pelvis, fetus and productivity. There may be other factors that influence the progress of childbirth.

Calkins has suggested that the sigmoid colon is located in the left 1/4 region of the left pelvic cavity, and the bladder is located in the right 1/4 region. The regular expansion of these two organs can push the fetal head into the two remaining 1/4 regions, left front or right rear. It is speculated that the fetus in the right side of the pillow is affected by the three major factors of childbirth in the process of forward rotation, and is also affected by the periodic expansion of the bladder in the right 1/4 area, which makes the time required for the fetal head to move to the front position to be prolonged. The left posterior fetus is affected by the regular expansion of the sigmoid colon in the left posterior 1/4 region during the forward rotation, which causes the fetal head to rotate forward. Therefore, the left posterior position of the occiput is transferred to the anterior delivery. The right posterior position is short to the previous birth.

However, the rotation in the posterior position of the occipital region failed. The occipital posterior position of the occipital posterior occipital posterior occipital posterior occipital posterior occipital cerebral palsy was delayed. The fetal head was never connected, 11 cases continued in the right side of the 6 cases of cesarean delivery, 1 case of fetal head has not been connected, Kurcipal reported that the primipara persistent occipital left posterior labor (14.92h) is more persistent than the right occipital ( 12.62h) long; and the abnormality of labor and the high rate of surgical delivery, it is considered that the persistent left occipital posterior is more abnormal than the persistent right occipital posterior, further analysis of their relationship with the three major factors of childbirth, and found that the pelvis lasts behind the left occipital The proportion of stenosis and fetal oversize (3 500g) is higher than that of persistent occipital occipital, suggesting that it may be related to pelvic stenosis after occipital left occlusion, and the relative head basin is not more closely related. This may be due to Part of the persistence in the right posterior position of the occiput is caused by the bladder factor. It is obvious that there is no pelvic stenosis or fetal oversize. As for whether there are other factors affecting the left occipital posterior occipital posterior posterior position, it needs further study.

Persistent post-occipital dystocia prevention

Persistent posterior occipital position is one of the common head dystocia. Common causes are pelvic abnormalities, large fetuses, poor fetal head flexion and uterine atony, cesarean section and high surgical output. If not found in time, Reduced labor, resulting in delayed labor, postpartum hemorrhage, genital tract injury, puerperal infection, fetal distress, intracranial hemorrhage, perinatal death and other maternal and child complications, vaginal examination can confirm the diagnosis, except for the obvious head basin is not called, Trial production, maintain good productivity during the labor process, closely observe the expansion of the cervix and the decline of the fetal head, after full trial production, if the fetal head can not be connected, or the fetal head is connected, but not up to 2 or blocked in 2 Level, should be cesarean section, when the post-occipital fetal head reaches 3 or less, it can be used for vaginal surgery.

Persistent post-occipital dystocia complications Complication

Postpartum hemorrhage: If the mother has bleeding after birth, the prognosis is serious, and the shock is longer and the duration is longer. Even if rescued, serious secondary anterior pituitary dysfunction (Sheehan syndrome) sequelae may occur. Therefore, special attention should be paid to prevention and treatment.

Hypopic uterus weakness: should be alert, sometimes the placenta has been discharged, the uterus is slack, a large amount of blood accumulates in the uterine cavity, and vaginal bleeding is only a small amount, the maternal symptoms of excessive blood loss, so in addition to pay close attention to vaginal bleeding after delivery, should also pay attention Uterine contraction. The visual measurement of vaginal bleeding is much less than the actual amount of blood loss, so the measurement must be collected with a curved disc. There is uterine atony before the delivery, the placenta delivery process and excessive bleeding after delivery, the diagnosis is no difficulty, but be alert to the aforementioned hidden postpartum hemorrhage and may be associated with birth canal laceration or placental factors.

Soft birth canal laceration of cervical laceration.

Coagulation dysfunction has a tendency to bleed easily before or during pregnancy, and when there is damage to the placenta or the birth canal, hemorrhagic dysfunction.

Persistent post-occipital dystocia symptoms Common symptoms Defecation sensation Fatigue After labor, severe pain, cervical edema, fatigue, postpartum poor flexion, small stenosis, anal swell, postpartum, fetal head, late connection

Symptom

(1) After the delivery, the fetal head is connected late, which may lead to weak uterine contractions, slow expansion of the cervix and stagnation of the fetal head.

(2) Maternal conscious angulation and bowel movements are early.

(3) maternal fatigue: related to the maternal not to open the mouth of the palace is not consciously holding hands.

(4) Cervical edema, the progress of labor is slow.

(5) If the fetal hair is seen in the vaginal opening, after repeated contractions and breath holding force, the fetal head continues to decline, and it should be thought that it may be a persistent posterior position.

2. Signs

(1) Abdominal examination: At the bottom of the palace, the fetal hip is touched, and the fetal back is biased to the rear or side of the mother. The front abdominal wall is easy to touch the fetal limb. If the fetal head is connected, sometimes the fetal ankle can be touched on the side of the fetal limb above the pubic symphysis. On the face, because the fetal back is biased to the rear or side of the mother, the fetal heart sound is easy to hear on the lower side of the umbilicus, that is, the part close to the fetal back is heard most clearly.

(2) Anal examination: anal examination of the pelvic cavity emptiness, the fetal head sagittal suture is located in the pelvic slant or anteroposterior diameter, the posterior occipital posterior sac is located behind the pelvis, the anterior iliac crest is located in front of the pelvis, touching the anterior iliac in the pelvis right In front, the posterior malleolus (occipital) is the posterior left posterior position of the pillow in the left rear of the pelvis, and vice versa.

(3) vaginal examination: When the cervix is open, there is fetal head edema, and when the skull overlaps, the vaginal examination is feasible. The fetal position is determined according to the fetal auricle and the tragus. If the auricle is facing the back of the pelvis, the diagnosis is made. For the back of the pillow. Combined with clinical symptoms and signs, the posterior occipital position is generally not difficult to diagnose. If necessary, combined with B-ultrasound examination, the use of ultrasound imaging to understand the fetal face and occipital position, can be diagnosed, timely treatment, no need for repeated anal examination and vaginal examination. Strive to find the back of the pillow in the early stage of labor, so that it can be treated in time to avoid prolonged labor.

1. Funnel-shaped pelvis is prone to persistent posterior occipital pelvis (including male and pelvic pelvis). If the fetal head is found in the early stage of clinical use, the possibility of persistent posterior occipital position should be guarded.

2. Persistent post-occipital labor pattern showed various abnormalities. Chen Lian reported 150 cases of persistent posterior occipital position. Except one case was normal, 149 cases had different types of abnormalities;

1 fetal head is blocked at the entrance of the pelvis, mostly manifested as prolonged latency or (and) active early (cervical dilatation 3 ~ 5cm) cervical dilatation delay or block;

2 active late (cervical dilatation 8 ~ 9cm) cervical dilatation delay or (and) block, can be expressed as prolonged active or prolonged deceleration;

3 After the cervix is opened, the fetal head is delayed or delayed, and the second stage of labor is prolonged.

3. Back pain The maternal pain is soon after the labor, and it appears with the contraction of the uterus, which is aggravated as the labor progresses.

4. The maternal appearance of the lower screen in advance when the active early cervical cervix only opens 3 to 5 cm, the maternal has a lower screen feeling, which is caused by the fetal head pressing the rectum at the entrance of the pelvis.

5. The anterior lip of the cervix often has edema and the cervix is dilated to 8 to 9 cm. It is not easy to open.

6. Anal bulge in the second stage of labor, the maternal anus swells severely.

7. Abdominal examination 2/3 of the mother's abdomen is occupied by the fetal limbs, and the fetal back is biased to the side of the mother's body. The fetal heart sounds are heard in the right lower abdomen of the mother, whether the left or the right of the pillow, but the right rear position of the pillow is louder. Because the left chest of the fetus is close to the anterior abdominal wall of the mother (Fig. 6), the pubic symphysis of the lower abdomen is not the round and hard cranial bone of the fetus, but the fossa of the fetus. The position of the left or the right of the occiput is determined according to the position of the fetus. In the lower right side of the mother's abdomen, the fetal part is touched to the left posterior position of the pillow, and the left lower part touches the fetal part of the lower part of the pillow (Fig. 7).

8. Anal examination combined with abdominal examination in the early stage of labor, when the cervix is only expanded 3 to 5 cm, when the fetal head edema is not obvious, the sagittal suture can be seen through the anus examination, and the sagittal suture is in the left slant of the pelvis. On the upper right side of the pubic symphysis and the fetal sputum, the left posterior position of the occipital pillow can be suspected; the sagittal suture is on the right slanting diameter of the pelvis, and the left upper part of the pubic symphysis is paralyzed, and the right rear of the pillow can be suspected.

9. Vaginal examination is a necessary means to diagnose the posterior position of the pillow. To be a qualified obstetrician, the accuracy of the vaginal examination to determine the position of the fetus should be 80% to 90%. When the labor progress is abnormal, the expansion of the cervix can reach 3cm or more. The two fingers can be inserted into the uterine cavity to determine the orientation of the fetal head. When the cervix is nearly open or open, the fetal head deformation and fetal head edema are not obvious, and the accuracy is up to 90%.

Persistent post-occipital dystocia examination

1. The accuracy of ultrasound imaging examination can reach more than 90%. Ultrasound imaging can be used to understand the changes of fetal head orientation, and timely treatment is needed without repeated vaginal examination.

2. X-ray diagnosis of the axial position of the axial papilla opening (pointing to the occipital bone), the lateral spine of the fetal spine in the posterior aspect of the mother close to the mother spine, indicating that the fetus is the posterior position of the pillow, and then according to the front and rear, fetal spine On the left or right side of the mother, it is decided whether it is the left posterior or the right posterior.

Diagnosis of persistent occipital dystocia

1. Abnormal labor and anterior vaginal examination of the occipital sinus, although the direction of the sagittal suture is consistent, but the posterior iliac crest is in the front, and the posterior iliac crest is in the posterior, through the auricle and tragus. the difference.

2. The abnormality of labor and the high vaginal examination of the fetal head showed that the sagittal suture of the fetal head was consistent with the anterior and posterior diameter of the pelvic entrance. The front and the posterior iliac crest could be touched at the same time, and the cardia was at the same horizontal line.

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