Abdominal Myomectomy

Abdominal myomectomy is a major surgical procedure in which uterine fibroids are removed from the uterus and the uterus is then repaired. This procedure is advantageous for women with symptomatic fibroids that are either too large or too numerous to be removed using laparoscopic myomectomy. It is also the current treatment of choice for most women who are actively trying for pregnancy. A problem with this procedure, as with all surgical procedures used to remove fibroids, is that there is a high risk of recurrent fibroids.

Surgical procedures can remove whatever fibroids are present at a particular time, but they do not stop the process of fibroid formation, and new ones may develop.

Some studies have suggested that myomectomy has a greater incidence of surgical morbidity (bad side effects or complications but not death—which is termed mortality) than hysterectomy, but most studies suggest that these two procedures are similar with regard to such problems. Still, an abdominal myomectomy does violate many of the principles of surgical therapy; therefore, when performed by less experienced surgeons, it may be a riskier procedure. It is important, then, to choose a surgeon with significant experience.

Surgical procedures are usually begun by controlling the major blood vessels, but this cannot be done in a myomectomy because the procedure is designed to save the uterus, and therefore the major blood supply cannot be cut off. A number of strategies have evolved to limit blood loss at the time of surgery. Women contemplating myomectomy should be aware of the options (described below) and discuss them with their surgeon. Not all surgical procedures have to be identical, but being aware of all the options is important.

Minimizing Blood Loss

To prevent excessive blood loss or the consequences of this kind of blood loss, the following five options should be considered:

1. Maximize preoperative blood count. Women contemplating surgery for uterine fibroids should be taking iron and vitamins to increase their hematocrit (the percentage of red blood cells) prior to surgery. The degree to which a woman has anemia before the procedure dictates the amount of iron that may be necessary. Given that many women with fibroids are chronically anemic due to menstrual blood loss, iron intake is especially important. Many physicians recommend iron for women who are anemic as a result of having fibroids, but they neglect to recommend multivitamins. Many vitamins are necessary to make new red blood cells, and thus the combination is important.

This is an approach most women should use. It is relatively inexpensive and easy to do. The major limiting factor is that taking iron supplements commonly causes constipation. This can be particularly annoying when the fibroids are also pressing on the bowel and contributing to constipation as well. There are, however, many different formulations of iron including pills and liquids, pills coupled with stool softeners, and slow-release formulations. If you have significant constipation, it is worth working with your doctor and your pharmacist to find a better iron supplement for you.

2. If iron and vitamins alone do not resolve the anemia, there are several alternative strategies for raising the blood count. The most common is the use of drugs called gonadotropin-releasing hormone (GnRH) agonists (Lupron, Zoladex, and Synarel). These drugs, which work by shutting down the reproductive system at the level of the hypothalamus, are discussed in detail in this article: Gnrh-agonists, add-back-therapies and gnrh-antagonists as treatments for fibroids.

They first cause an increase in hormones, called the flare, and then a few weeks later they cause a state commonly called a “medical menopause.” The “medical menopause” phase is an advantage for treating fibroids because it creates menopausal levels of estrogen and progesterone and causes more than 90 percent of women to stop having periods. During the initial, or flare, phase, some women have a very heavy flow that, for women with severe anemia, can be a significant problem.

The “medical menopause” state is associated with hot flashes and bone loss, as is normal menopause. These side effects limit the long-term effectiveness and safety of this approach to resolving anemia, but the US Food and Drug Administration (FDA) has approved the use of Lupron in the preoperative management of uterine fibroids when used with iron in preparation for surgery. This is the only FDA-approved medical treatment for uterine fibroids. However, other GnRH agonists should work in a similar fashion. GnRH agonists are the most widely used drugs for inducing amenorrhea (the lack of periods) prior to surgery. Other drugs, such as continuous birth control pills, progesterone, synthetic progestins, and danazol (synthetic androgen), also may successfully stop menstruation. The GnRH agonists also decrease the size of the uterus, which is not the case with these other drugs and the reason that GnRH agonists are more widely used for preoperative treatment. A smaller uterus can also make surgery easier.

3. Intraoperative blood loss can be limited by specific surgical techniques. The most common are the use of a tourniquet, the injection of a drug called vasopressin into the myometrium, the use of arterial clamps, and the Cell Saver. A tourniquet places pressure over the major blood vessels leading to the uterus and thus decreases the blood flow during the operation. Significant surgical skill is needed to place a tourniquet safely, since there are many blood vessels and other vital structures in this area. In addition, certain fibroids arising from the lower uterine segment or the cervix make it difficult to safely place a tourniquet in all cases. The second strategy to limit blood loss is injecting a dilute solution of vasopressin into the myometrium. This causes local blood vessel constriction. Vasopressin is a natural hormone that is made by the pituitary gland. It is used in a very dilute solution over the points where incisions are made for the myomectomy but can cause significant problems if injected into the circulation. Some surgeons place vascular clamps over the ovarian arteries and veins while operating.

Finally, instruments such as the Cell Saver can be used intraoperatively. The Cell Saver allows blood that is normally lost during surgery to be filtered and processed so that the patient’s red blood cells can be returned to her. Instead of going through a suction tube and being discarded, the red blood cells are saved and given back through the intravenous (IV) line like a transfusion, but with your own blood.

4. With women who have persistent anemia, sometimes either intravenous iron infusion or erythropoietin can be used to stimulate blood production. Many women with fibroids have an iron deficiency, and some women cannot absorb enough iron from their intestines with liquid iron or iron tablets. Intravenous iron infusion is useful only with women who are very iron-deficient. Intravenous iron can cause serious allergic reactions and needs to be carefully supervised. It is usually done only in a hospital setting. Erythropoietin, on the other hand, is the body’s natural hormone for stimulating blood production. It is unnecessary in most women with iron deficiency because the body is already naturally stimulating the production. However, in certain circumstances, such as women who need significant blood replacement but cannot have a blood transfusion because they are Jehovah’s Witnesses (for example), erythropoietin can be an option.

5. Finally, the use of autologous blood transfusion can be useful. If you are able to build up your blood count, then several units of your own blood can be extracted and stored for your later use. Donating the units of blood will stimulate additional blood production, and if transfusion is required during surgery, receiving your own blood poses less risk than receiving blood donated from someone else. This option is not available as an emergency strategy; it does not help to give blood on Monday for use during surgery on Wednesday. At least several weeks are needed to build up the blood count to normal following donation of a unit of blood before you can safely have surgery.

Incisions

Abdominal myomectomies require an abdominal incision. The size can range from a “bikini” cut (a very small horizontal incision that can be hidden by a bikini bottom) to a large vertical incision, extending above the belly button. Although surgical skill is a factor in the surgeon’s choice of which incision to use, with women who have fibroids a significant factor in making this decision is the size of the uterus. If the fibroids extend way above the belly button and up toward the liver, then trying to remove these fibroids through a bikini incision is impossible, or at least ill advised. Sometimes, however, there are other options.

Just as either a vertical or a horizontal bikini incision can be used to cut into the skin, the deeper layers of the abdominal wall can be approached in different ways, too. Using a short horizontal cut on the outside, for example, does not always mean that the same type of incision has to be used on the inside.

The most common type of incision is a Pfannenstiel. With this incision, the surgeon makes a bikini cut in the skin but does not continue to cut horizontally through the major abdominal muscles (the rectus abdominus); the two sides of the rectus abdominus, or the muscle bellies, are separated in the midline instead. Thus, the deeper layer has a vertical incision, which explains why women with this kind of incision can have postoperative pain near the belly button, far from the incision they see. The rectus muscles limit the amount of room that can be used to operate with a Pfannenstiel incision. The bladder also limits the room at the base of the incision. Generally a Pfannenstiel incision leads to less postoperative pain and better functioning of the abdominal muscles after surgery, but it does not always give the surgeon enough room to deal with all of the fibroids.

A Maylard incision consists of a bikini cut through the skin and a transverse incision in the deeper layers. This means that the rectus muscles are cut crosswise. Because this incision provides more room to work, it can allow a larger uterus to be approached without resort-ing to a vertical incision. However, a Maylard incision may result in more postoperative discomfort and more difficulty getting the mus-cles to work normally following surgery.

Traditionally, a vertical incision has been avoided not only because it is cosmetically less attractive but also because of concerns that it will pose more difficulty in healing. Because all the blood vessels that go to the abdominal wall come from near the spine and back and then meet in the midline, at the front of the body, the midline has less blood supply, making it less able to heal. In practice, however, for most women with fibroids who are young and healthy, this does not appear to be a major issue.

Sometimes it is difficult to make a final decision until the day of surgery. In addition to the size of the uterus, the mobility of the uterus (how easily it moves) can be important in deciding which incision is appropriate. Mobility is much easier to assess when a woman has had anesthesia and is not uncomfortable. Rarely, the uterus feels significantly bigger or smaller in the operating room than it did in the office. Having an updated imaging study like an ultrasound significantly decreases the possibility that the uterus will be unexpectedly large or small, but surprises do sometimes happen.

Surgeons typically gauge the size of the fibroid uterus by its relationship to the pelvic bones, just as we do for the pregnant uterus. However, with uterine fibroids, there can also be substantial volume behind the uterus and in fact below or behind the cervix, and this volume can be very important in the surgical approach. Without taking this volume into account, the size of the uterus is underestimated.

Likewise, the uterine size will usually be overestimated in a heavier woman, since the surgeon is feeling the size of the uterus with the intervening abdominal wall. If the abdominal wall is 2 inches thick, the uterus will “feel” much bigger than if the wall is a quarter of an inch thick. It is almost like having the same package and putting different amounts of wrapping around it. Keeping these two factors in mind, a skilled surgeon is better able to gauge the correct size of incision needed.

Surgical Complications and How to Minimize Them

To minimize the risk of postoperative infection, most physicians prescribe at least one dose of antibiotics to be given through the IV right before the surgery starts. Some physicians continue antibiotics for their patients for the first 24 hours, as well.

Another concern is the risk of blood clots in the legs (deep venous thrombosis, or DVT). Clots that form in the legs may break off and move toward the lungs (pulmonary embolus, or PE); this is a more serious threat than DVT. There are several strategies for decreasing the risk of DVTs (and thus PEs), including physical compression and injections of blood-thinning agents. Compression devices include elastic stockings and pneumoboots (boots that puff air around the lower legs during the surgery). Blood thinners are typically started prior to the surgery. Both compression devices and blood thinners are continued until the woman is up and walking.

Preventing adhesions (bands of scar tissue that bind two parts of tissue together) is also important following myomectomy and is particularly important for women planning pregnancies. Surgical technique in terms of the types of incisions, the suture used, and the handling of tissue appears to be a factor in the formation of adhesions.

In the past, attempts to minimize adhesions involved instilling various fluids or drugs (or both) into the abdomen following surgery. This approach has largely been replaced by various adhesion barriers placed over the uterine incisions to keep other structures from sticking to the uterus. Although a number of agents have been tested, there is no consensus on the ideal regimen, and just like other myomectomy issues, discussing adhesions and their prevention with your surgeon is useful prior to surgery.

Teachings about abdominal myomectomy also suggest that, for a woman who becomes pregnant after undergoing this procedure, a cesarean section should be required if the myomectomy incision goes all the way through the uterine wall and into the endometrial cavity. Although there is no clear evidence that a cesarean section (also referred to as a C-section) is required, it has long been a practice and has resulted in many healthy pregnancies for both mother and baby. The practice was initially begun because it was well established that having a cesarean section with a vertical uterine incision (a classical C-section) increased the risk of uterine rupture in a subsequent pregnancy. In the initial studies that reported this risk with classical C-section, the risk of uterine rupture with myomectomy was also assessed. The risk of uterine rupture following myomectomy was significantly lower than what was seen following classical C-section. There are many ways in which a myomectomy is a very different procedure than a cesarean section. Nonetheless, C-section after abdominal myomectomy is the usual practice, and few practitioners deviate from this teaching.

>Finally, given the high risk of recurrent surgery following abdominal myomectomy, Most gynaecologists believe the strategy should be to remove all fibroids that are visible or palpable (able to be felt). Using many of the aforementioned techniques minimizes risks, and there are very few fibroids that are “too dangerous” to remove.

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