breech dystocia
Introduction
Brief introduction of breech dystocia Breechpresentation is the most common abnormal fetal position, accounting for 3% to 4% of the total number of full-term delivery. The breech presentation is based on the humerus as the indication point. It is divided into the left front, the left left, the left left, the right front, the right and the right. The breech is delivered. The circumference of the buttocks is smaller than the head. Delivery, the fetal head is delivered later than the carcass, the fetal head has no chance of deformation, and it is easily blocked by the pelvis. During the delivery process, the umbilical cord is easily stressed and deprived of oxygen. Therefore, the fetal hip should be delivered as soon as possible, usually no more than 5-8 minutes. Otherwise the life of the fetus is dangerous. basic knowledge The proportion of illness: 3% to 4% (breech dystocia is the most common abnormal fetal position, accounting for 3% to 4% of the total number of full-term delivery) Susceptible population: pregnant women Mode of infection: non-infectious Complications: premature delivery umbilical cord prolapse
Cause
Breccia dystocia
Fetal developmental factors fetal brain development abnormalities (30%):
The incidence of breech presentation such as microcephaly, no brain, hydrocephalus, etc. is significantly higher than that of normal children.
Fetal activity space is limited or too large (35%):
Such as uterine malformation, pelvic stenosis, uterine or pelvic tumor obstruction of the pelvic cavity, relaxation of the maternal abdominal wall, excessive amniotic fluid, etc. easily form the breech.
Cause of breech presentation (25%)
Pelvic stenosis, tumor of the birth canal, loose abdominal wall, multiple births, excessive amniotic fluid, fetal malformations, etc.
(1) The uterine cavity is wide, the amniotic fluid is more, and the maternal abdominal wall is excessively slack, and the fetus is frequently prone to breech in the uterus.
(2) uterine malformation, small uterine cavity, limited fetal activity in the uterus, the fetal head can not be rotated downwards, easy to become breech.
(3) placenta previa, pelvic stenosis and pelvic tumor obstruction of the pelvic cavity, all affect the fall of the fetal head into the basin, easy to become breech.
(4) The amniotic fluid is small, the legs of the fetus can not be flexed, and it is straight and straight, which affects the bending or rotation of the carcass and is easy to become the breech position.
Pathogenesis
Taking the right front position as an example, the following is explained:
1. The baby's hip is delivered
After labor, the fetal buttocks are connected to the right slant diameter of the pelvic entrance with the intertrochanteric diameter. The front hips descend slightly faster, reaching the pelvic floor first. Under the pelvic floor resistance, the front hips turn 45o to the right side of the mother to the rear of the pubic symphysis. The internal rotation movement is completed. At this time, the intertrochanteric diameter is consistent with the anterior and posterior diameter of the parent pelvic outlet, and the fetal hips continue to descend. The carcass is adapted to the lateral stiffness of the birth canal, and the posterior gluteal is delivered from the perineal anterior border, and then the carcass is slightly straightened. The anterior hip is delivered under the pubic bone, followed by the fetal leg and the fetal foot.
2. The shoulder is delivered
After the fetal buttocks and the lower extremities are delivered, the carcass rotates to the left, and the back of the fetus rotates to the front or the right front. The fetal shoulders are connected to the right slant or transverse diameter of the pelvic entrance and descend along this path. When the shoulders descend to the pelvic floor. The front shoulder is rotated 45o to the right under the pubic arch, so that the shoulder diameter is consistent with the anterior and posterior diameter of the pelvic outlet. Similarly, the carcass is adapted to the lateral flexion of the birth canal, and the posterior shoulder and the posterior upper limb are delivered from the perineal anterior border, followed by the lateral extension of the carcass. The front shoulder and the front upper limb are delivered from the pubic arch.
3. The fetal head is delivered
When the shoulder passes through the perineum, the sagittal suture of the fetal head is connected to the left slant or transverse diameter of the pelvic inlet, and descends along the diameter line. At the same time, the fetal head is flexed, and when the fetal occipital bone reaches the pelvic floor, it rotates to the left front of the mother pelvis. 45o, the occipital bone is united toward the pubic symphysis, and when the occipital bone is concave under the pubic arch, the anterior uterus is used as the fulcrum, and the fetal head continues to flex, so that the sputum, face and amount are delivered from the perineal anterior border, and then the occipital bone is delivered from the pubic bone. .
The delivery mechanism of the lateral position and the posterior position of the ankle is only different from the right anterior position when the rotation is in the inner rotation. The transverse position of the iliac crest is 90o, and the posterior position of the iliac crest is 135o.
Prevention
Breech dystocia prevention
Before 30 weeks of gestation, the gluteal spleen can turn itself to the first exposure, no need to deal with it. If the lap is exposed after 30 weeks of pregnancy, it should be actively corrected. The commonly used correction method can be seen in the treatment during pregnancy.
Complication
Breech dystocia complications Complications premature umbilical cord prolapse
l. Breethe delivery has a greater impact on perinatal children, with more complications.
(1) Premature birth: According to Morgan's report of 16327 breech delivery in 1964, premature birth accounted for 32%. In addition to the effect of premature birth on the fetus or baby, breech delivery is more dangerous than the head position. According to statistics, each group of fetuses In the same age, the weight of the breech is lower than that of the non-breech. On the other hand, the difference in the head-hip circumference of premature infants is more disparate than that of the full-term, so the risk of childbirth is greater, so the mortality rate Increase.
(2) Umbilical cord prolapse: the incidence of umbilical cord prolapse in the breech position is 4% to 5%, which is 10 times of the head position. The umbilical cord prolapse rate with the first breech completely filling the cervix is the lowest. , only about 1%; full breech position is 2% to 5%; foot first exposed due to the largest gap exposed and up to 10% to 18%.
(3) Asphyxia and injury: the incidence of birth injury is very high. In difficult labor, the incidence of neonatal injury is 20%, even if the delivery is smoother, 3.5%; the most serious injury is intracranial hemorrhage. The incidence rate is 10 times higher than the head position, which is one of the main causes of death of the breech baby. The main cause of intracranial hemorrhage or injury is when the fetal head passes through the pelvis and bears a large tension in a very short period of time. Undeformed, intracranial ligaments (such as cerebellar canopy, etc.) and brain tissue tear, bleeding and contusion, more damage occurs in the head basin, pelvic stenosis or in the case of the cervix is not open, another On the other hand, due to the difficulty of traction, diffuse bleeding of the brain parenchyma occurs when the brain is deprived of oxygen for a long time, which can bring about lifelong sequelae. In addition, there is a so-called "minimal brain damage", often in early childhood. Because intellectual performance such as reading, writing, comprehension, and communication lags behind normal children, the incidence in the breech is also twice that of the head position.
In addition to brain damage, the incidence of fracture and dislocation of the neck, tibia, and femur, as well as brachial plexus injury, is also high. Other injuries such as the pharynx or abdominal organs including the liver, spleen, and bladder are occasionally see.
(4) Malformation: Congenital malformations in the breech, such as hydrocephalus, no brain, congenital dislocation of the hip, etc., are higher than the head position, and Brennei found a deformity rate of 2.4% in 29,000 cases. In the 10,000 cases of breech position, it was 6.3%, and the incidence of malformation of the breech position was about 1 to 2 times that of the head position.
2. Breech delivery also has adverse effects on the mother
(1) The breech position is irregular in the exposed part, so that the pressure of the anterior amniotic sac is uneven, and premature rupture of the membrane is easy.
(2) Due to the irregularity of the first exposed part, it is not easy to closely contact the lower part of the uterus and the cervix, which may easily cause uterine contraction and weakness, resulting in prolonged labor.
(3) If the cervix has not been opened before the early hip traction, or the breech delivery technology is improperly controlled, or the rough movement can cause vaginal tears, even the perineal III degree tear, cervical laceration, severe cases can affect the uterus The lower part, and even the uterus rupture.
Symptom
Symptoms of breech dysfunction Common symptoms Hip-infant fetus incomplete breech first exposed fetus one-armed first exposed after labor painful severe fatigue postpartum poor flexion sensation funnel pelvic nodules
1. According to the posture of the lower limbs of the fetus, it is divided into the following three categories:
(1) The most common frank breech presentation (frank breech presentation), the fetal double hip joint flexion, the knee joint straight, first exposed to the hip, also known as the leg straight hip first exposed.
(2) Complete breech presentation is more common. The fetal knee joint and the double hip joint are flexed. They are first exposed as hip and biped, also known as mixed breech presentation.
(3) The minimum incomplete breech presentation is at least one foot or two feet, one knee or two knees or one foot and one knee. The knee presentation is temporary, and the labor begins to turn. For the foot presentation.
2. Clinical manifestations
(1) Symptoms: Pregnant women often feel the sensation of ribs in the season. After the birth, the fetal foot can not fully expand the lower uterine segment and the internal cervix, often causing uterine weakness and prolonged labor.
(2) Signs:
1 Abdominal examination: The four-step palpation of the uterus is vertical and elliptical. The bottom of the palace can touch the round and hard fetal head. The pressing has obvious floating ball feeling. If it is not connected, it can touch irregularly above the pubic symphysis, soft and wide. Fetal buttocks, the fetal heart is most clearly auscultated at the upper left or upper right of the umbilicus; if it is connected, the fetal heart is most clearly auscultated under the umbilicus.
2 anal examination: anal examination can touch soft and irregular fetal hip or fetal foot, fetal knee.
3 vaginal examination: when the anal examination can not be determined, a vaginal examination is required. If the membrane is broken, it can directly contact the fetal anus, the ischial tuberosity and the tibia and other fetal hip characteristics. At this time, attention should be paid to the facial identification. The anus can be touched with the two ischial tuberosity in a straight line. The finger is placed in the anus and has a sense of contraction. When the finger is removed, there is meconium on the finger sleeve. If it is a face, the mouth and the two metatarsbone are triangular, and the finger is placed in the mouth. Touching the gums and mandible, accurate palpation of the tibia is very important for confirming the position of the fetus. When the whole hip is exposed, the foot can be touched. The orientation of the big toe can distinguish the left and right feet. At the same time, it should be differentiated from the fetal hand. Touch the external genitalia, and pay attention to the presence or absence of umbilical cord prolapse.
3. Hip type
(1) Full breech position: Hip joint flexion of the fetal legs, knee flexion, first exposed to the hip and both feet, clinically more common.
(2) Single breech position: the femoral femoral joint flexes to the abdomen of the fetus, and the legs extend straight in front of the fetal chest, which is called the leg straight breech position, the fetus's hips are flexed, the knees are straight, the hips are first exposed, about 50% of the breech position.
(3) Incomplete breech position: including knee or foot position, the fetus is one foot or two feet, one knee or both knees are exposed first, clinically less common, prone to premature birth, early rupture of membrane, umbilical cord prolapse and the like.
Examine
Breech dystocia check
B-ultrasound to ensure the type of gluteal first exposure, ultrasound examination can determine the type of breech presentation, fetal size, abnormalities and uterus, placenta with or without abnormalities.
Diagnosis
Diabetic dystocia diagnosis
According to the clinical symptoms and signs, most of the breech presentation can be diagnosed. If it can not be diagnosed, ultrasound can be used.
Clinical examination
Abdominal examination
At the end of the palace, you can have a round and hard fetal head. Above the pubic symphysis, you can have a soft and wide fetal buttocks. The position of the fetal heart sound is higher, on the upper left or upper right side of the umbilicus.
2. Anal finger examination or vaginal examination
If the abdominal examination can not be confirmed as the head or breech position, you can do anal finger examination, such as emptiness in the pelvis, not a round and hard fetal head, but touch the soft but irregular shape of the hip. Or sputum and fetal foot, you can diagnose the breech position, if the anal examination can not be diagnosed, you can do a vaginal examination to distinguish the type of breech, understand the condition of the cervix and whether there is umbilical cord prolapse, such as the membrane has been broken Can directly reach the fetal buttocks, external genitalia and anus, such as the part of the foot like the fetal foot, can be distinguished from the toe and the finger and the heel without the heel, the baby or the fetal foot Fashion should pay attention to distinguishing from the facial position. In the breech position, the anus is connected with the ischial nodules on both sides. When the finger is placed in the anus, there is a contraction of the annular sphincter, and there is meconium on the fingertip; The humerus and the humerus on both sides are distributed in an isosceles triangle. The finger can be placed in the mouth to reach the gums and the mandible can be seen.
3. Ultrasound examination
In addition to determining the breech position, the B-mode ultrasound examination can determine whether the fetus is deformed or not, and can measure the fetal biparietal diameter, head circumference and abdominal circumference to estimate the size of the fetus.
