Tuesday, July 14, 2009

CESAREAN DELIVERY

INTRODUCTION — A cesarean delivery (also called a surgical birth) is a surgical procedure used to deliver an infant. It requires regional (or rarely general) anesthetic to prevent pain, and then a vertical or horizontal incision in the lower abdomen to expose the uterus (womb). Another incision is made in the uterus to allow removal of the baby and placenta. Other procedures, such as tubal ligation (sterilization), may also be performed during cesarean delivery
Cesarean deliveries may be performed because of maternal or fetal problems that arise during labor, or they may be planned before the mother goes into labor. More than 30 percent of births in the United States occur by cesarean delivery.
REASONS FOR CESAREAN DELIVERY — Some women who intend to deliver vaginally will eventually require cesarean delivery. Reasons for this include the following: Labor is not progressing as it should. This may occur if the contractions are too weak, the baby is too big, the pelvis is too small, or the baby is in an abnormal position. If a woman's labor does not progress normally, the first step is usually to rupture her membanes (bag of water). In many cases, the woman will be given a medication (Pitocin®/oxytocin) to be sure that contractions are adequate for several hours. If labor still does not progress after several hours, a cesarean delivery may be recommended. The baby's heart rate suggests that it is not tolerating labor well. This may be due to a placental problem or compression of the umbilical cord. The baby is in a sideways or breech position (buttocks first) when labor begins. Heavy vaginal bleeding. This can occur if the placenta separates from the uterus before the baby is delivered (called a placental abruption). A medical emergency threatens the life of the mother or infant
PLANNING CESAREAN DELIVERY — A planned cesarean delivery is one that is recommended because of the increased risk(s) of a vaginal delivery to the mother or her infant. Cesarean deliveries that are done because the woman wants, but does not require, a cesarean delivery are called "maternal request cesarean deliveries". There are a number of medical and obstetric circumstances that a healthcare provider would recommend scheduling a cesarean delivery in advance, including the following: The mother has had a previous cesarean delivery or other surgery in which the uterus was cut open. A vaginal delivery is possible after cesarean delivery in some, but not all cases. There is some mechanical obstruction that prevents or complicates vaginal delivery, such as large fibroids or a pelvic fracture. The infant is unusually large, especially if the mother is diabetic. The mother has an active infection, such as herpes or HIV, that could be transmitted to the infant during vaginal delivery. The birth involves multiple gestation (twins, triplets, or more). The woman has cervical cancer. The infant has an increased risk of bleeding. The placenta is covering the cervix (called placenta previa).
There is some controversy about the preferred method of delivery in certain situations. These include some birth defects, such as spina bifida and fetal abdominal wall defects, and some maternal medical problems.
One of the most important factors in scheduling a cesarean delivery is making certain that the baby is ready to be delivered. In general, cesarean deliveries are not scheduled before the 39th week of pregnancy. An amniocentesis may be recommended to determine if the baby's lungs are fully developed, especially if cesarean is planned before 39 weeks of pregnancy.
Most women will meet with an anesthesiologist before planned surgery to discuss the various types of anesthesia available and the risks and benefits of each. Instructions about how to prepare for surgery will also be given, including the need to avoid all food and drinks for 10 to 12 hours before the surgery.
Advantages of planned cesarean — The advantages of a planned cesarean delivery include: It allows parents to know exactly when the baby will be born, which makes issues related to work, childcare, and help at home easier to address. It avoids some of the possible complications and risks to the baby. It avoids the possibility of postterm pregnancy, in which the baby is born two or more weeks after its due date. It helps ensure that a pregnant woman's obstetrician will be available for the delivery. It may offer a more controlled and relaxed atmosphere, with fewer unknowns such as how long labor and delivery will last. It may minimize injury to the pelvic muscles and tissues and the anal sphincters. These injuries sometimes occur during vaginal delivery, which may increase the risk of urinary or anal incontinence.
The benefits of planned cesarean delivery must be weighed against the risks. Cesarean delivery is a major surgery, and has associated risks.
Risks — Because cesarean delivery involves major surgery and anesthesia, there are some disadvantages compared to vaginal delivery. Cesarean delivery is associated with a higher rate of injury to abdominal organs (bladder, bowel, blood vessels), infections (wound, uterus, urinary tract), and thromboembolic (blood clotting) complications than vaginal delivery. Cesarean surgery can interfere with mother-infant interaction in the delivery room. Recovery takes longer than with vaginal delivery. Cesarean delivery is associated with a higher risk that the placenta will attach to the uterus abnormally in subsequent pregnancies, which can lead to serious complications. Cutting the uterus to deliver the baby weakens the uterus, increasing the risk of uterine rupture in future pregnancy. This risk is small and depends upon the type of uterine incision.
Infant risks — There are few risk of cesarean delivery for the infant. One risk is birth trauma, which occurs in 0.4 percent of cesarean deliveries. Temporary respiratory problems are more common after cesarean birth because the baby is not squeezed through the mother's birth canal. This reduces the reabsorption of fluid in the infant's lungs.
Potential complications — The most common complications related to cesarean delivery include infection, hemorrhage (excessive bleeding), injury to pelvic organs, and blood clots. Infection — The risk of postoperative uterine infection (endometritis) varies according to several factors, such as whether labor had started and whether the water was broken. Endometritis is treated with antibiotics.
Wound infection, if it occurs, usually develops four to seven days after surgery, but sometimes appears during the first day or two. In addition to antibiotics, wound infections are sometimes treated by opening the wound to allow drainage, cleansing with fluids, and removing infected tissue if needed. Hemorrhage — One to two percent of all women having cesarean deliveries require a blood transfusion because of hemorrhage (excessive bleeding). Hemorrhage usually responds to medications that cause the uterus to contract. Sometimes surgery, such as curettage (scraping the uterine cavity) is needed. In rare cases, when all other measures fail to stop bleeding, a hysterectomy (surgical removal of the uterus) may be required. Injury to pelvic organs — Injuries to the bladder or intestinal tract occur in approximately one percent of cesarean deliveries. Blood clots — Women are at increased risk of developing blood clots in the legs (deep vein thrombosis or DVT) or the lungs (pulmonary embolus) during pregnancy and the postpartum period. This risk is further increased after cesarean delivery. The risk can be reduced by using a device that gently squeezes the legs during and after surgery, called an intermittent compression device. Women at high risk of DVT may be given an anticoagulant (blood thinning) medication to reduce the risk of blood clots.
MATERNAL REQUEST CESAREAN DELIVERY — The concept of requesting a cesarean delivery is relatively recent. In the United States and most Western countries, pregnant women have the right to make choices regarding treatment, including how they will deliver their child.
A woman who wants to request a cesarean delivery should discuss this decision with her healthcare provider. He or she can provide information about each method of delivery and can help to relieve common fears about pain, the expected process of labor, as well as the woman's right to determine how she will deliver. The woman should also discuss the risks and benefits of maternal request cesarean delivery; in general, the risks are the same as those of a planned cesarean delivery
The woman should also discuss the possible need for a cesearean delivery with future pregnancies "Regardless of a woman's decision, it is possible to reconsider the decision at any time based upon a change in circumstances.
EMERGENCY CESAREAN DELIVERY — In some cases, cesarean delivery is performed as an emergency surgery, after attempting a vaginal delivery. Time may be of the essence, depending upon the situation. Cesarean deliveries performed due to concerns about the mother's or infant's health are started as quickly as possible.
In contrast, if a cesarean is performed because labor has not progressed normally or for other, less serious concerns about the baby's wellbeing, the surgery is usually begun within 30 to 60 minutes.
If an epidural was placed before the attempted vaginal delivery, it can be used to administer anesthesia for the cesarean delivery (a larger dose is necessary for cesarean delivery versus vaginal delivery). Otherwise, spinal anesthesia (or rarely general anesthesia) is given. PROCEDURE — After being admitted to the hospital, a woman may be given an oral dose of an antacid to reduce the acidity of the stomach contents. Another medication may be given to reduce the secretions in the mouth and nose. An intravenous line will be placed into the hand or arm, and an electrolyte solution will be infused. Monitors will be placed to keep track of blood pressure, heart rate, and blood oxygen levels.
Anesthesia — The woman is usually accompanied to an operating room before anesthesia is administered. A spouse or partner can usually stay with the woman in the operating room.
There are two types of anesthesia used during cesarean delivery: regional and less commonly, general. For a planned cesarean delivery, regional anesthesia is usually performed. Meeting with the anesthesiologist allows the woman to ask specific questions about anesthesia, and allows the anesthesiologist to identify any medical problems that might affect the type of anesthesia that is recommended. With epidural anesthesia, the anesthetic is injected into the epidural space surrounding the fluid-filled sac (the dura) around the spine. This numbs the abdomen and legs. With spinal anesthesia, the anesthetic is injected into the subarachnoid space in the lower back. The space contains the cerebrospinal fluid, so the anesthetic causes complete numbness, although the person is still awake. General anesthesia induces unconsciousness. This means that the mother will not be awake or aware during the procedure. After the anesthesia is given, the woman will fall asleep within 10 to 20 seconds and a tube will be placed in the throat to assist with breathing. General anesthesia carries a greater risk of complications because the endotracheal (breathing) tube can cause a severe change in blood pressure and because drugs given to the mother affect the infant.
Regional anesthesia is generally preferred because it allows the mother to remain awake during the procedure, enjoy support from staff and a family member, experience the birth, and have immediate contact with the infant. It is usually safer than general anesthesia. Many practitioners prefer spinal or combined spinal epidural over epidural techniques because of more rapid onset and better blockage of pain. The effect of regional anesthesia begins within a minute or so.
After the anesthesia is given, a catheter is placed in the bladder to allow urine to drain out during the surgery and reduce the chance of injury to the bladder. The catheter is usually removed within 24 hours after the procedure.
Skin incision — There are two basic types of incision: horizontal (transverse or "bikini line") and vertical (midline). Most women have a transverse skin incision, which is made 1 to 2 inches above the pubic hair line. The advantages of this type of incision include less pain, more rapid healing, and a lower chance that the wound will separate during healing.
Less commonly, the woman will have a vertical ("up and down") skin incision in the midline of the abdomen. The advantages of this type of incision include rapid access to the uterus (eg, if the baby is in distress or if the woman is bleeding excessively).
Uterine incision — The uterine incision can also be either transverse or vertical. The type of incision depends upon several factors, including the position and size of the fetus, the location of the placenta, and the presence of fibroids. The main consideration is that the incision must be large enough to allow delivery of the fetus without causing trauma.
The most common uterine incision is transverse. However, a vertical incision may be required if the baby is breech or sideways, if the placenta is in the lower front of the uterus, or if there are other abnormalities of the uterus.
After opening the uterus, the baby is usually removed within a minute or two. After the baby is delivered, the umbilical cord is clamped and cut and the placenta is removed. The abdominal skin is closed with either metal staples or reabsorbable sutures; staples are usually removed within 3 to 7 days while reabsorbable sutures are absorbed by the body and do not need to be removed. After the mother and baby are stable, she or her partner may hold the baby.
POSTOPERATIVE CARE — After surgery is completed, the woman will be monitored in a recovery area. Pain medication is given, initially through the IV line, and later with oral medications.
When the effects of anesthesia have worn off, generally within one to three hours after surgery, the woman is transferred to a postpartum room and encouraged to move around and begin to drink fluids and eat food.
Breastfeeding can usually begin anytime after the birth. A pediatrician will examine the baby within the first 24 hours of the delivery. Most women are able to go home within three to four days after delivery.
The abdominal incision will heal over the next few weeks. During this time, there may be mild cramping, light bleeding or vaginal discharge, incisional pain, and numbness in the skin around the incision site. For up to 6 weeks after the birth, nothing should be placed in the vagina (eg, tampons, douches). Heavy lifting and strenuous activity should be avoided during the first one to two weeks. Most women will feel well by six weeks postpartum, but numbness around the incision and occasional aches and pains can last for several months.
After going home, the woman should notify her healthcare provider if she develops a fever (temperature greater than 100.4º F [38º C]), if pain or bleeding worsens, or there are other concerns.
FUTURE DELIVERIES — Previously, obstetricians recommended that all women who had a cesarean delivery have the same for all future deliveries. However, this is no longer the case. Most women in the United States who have had one low transverse cesarean delivery choose to have a repeat cesarean delivery, although these women could try to have a vaginal delivery with the next pregnancy. Between 60 and 80 percent of women who try to deliver vaginally after a c-section are successful in delivering vaginally. However, women who have a vaginal birth after cesarean (VBAC) have a 1 percent chance that the uterus will rupture during delivery, which could affect the baby's health

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