Hysterotomy

Last updated
Hysterotomy
ICD-9-CM 68.0
MeSH D020883

A hysterotomy is an incision made in the uterus. [1] This surgical incision is used in several medical procedures, including during termination of pregnancy in the second trimester (or abortion) and delivering the fetus during caesarean section. It is also used to gain access and perform surgery on a fetus during pregnancy to correct birth defects, and it is an option to achieve resuscitation if cardiac arrest occurs during pregnancy and it is necessary to remove the fetus from the uterus.

Contents

There are several types of incisions that can be made, including a midline vertical incision and a low transverse incision. The incision is made using a scalpel and is about 1-2 cm long, but it can be longer depending on the procedure that is performed. [2] Other types of incisions are low transverse incision with T-extension in the midline, low transverse incision with J-extension, and low transverse incision with U-extension. These are used when low transverse incisions do not provide enough space in order to remove the contents in the uterus.

This incision also comes with possible risks and complications when the incision is made and during repair, including blood loss (possibly leading to anemia), wound infection, fertility problems, premature labor, postoperative pain, and many others. [3] In addition, a rare form of ectopic pregnancy known as scar ectopic pregnancy can occur. This is when there is abnormal implantation of an embryo onto the scar of the uterus. There is an increased risk of this complication occurring due to trauma from previous procedures utilizing hysterotomies, such as caesarean section and dilation, though the mechanism is unknown. [4] Closure of the hysterotomy incision made can be done with either a staple or a suture. Sutures are most commonly used, specifically double layer sutures. [5] [3]

Medical uses

Hysterotomy abortion

A hysterotomy is used to remove a fetus from the uterus, similar to a procedure known as caesarean section, in order to terminate a pregnancy in the second trimester of later. [6] It is typically used as last resort if dilation and curettage, dilation and electric vacuum aspiration, or manual vacuum aspiration fails to work. Dilation and curettage refers to the opening or widening of the cervix and scooping and scraping the tissues that are inside of the uterus. Electric vacuum aspiration utilizes a vacuum to remove the embryo that is in the uterus, but this method is more expensive than manual vacuum aspiration. [7]

Caesarean section operation Maygrier "Abbildungen..."; caesarian Wellcome L0015649.jpg
Caesarean section operation

Caesarean section

Although fetal delivery through caesarean section is a very common surgery done in the world, it comes with several risks including bleeding, infection, thromboembolism, and soft-tissue injury. During a caesarean section, a hysterotomy is utilized to make an incision in the uterus and remove the fetus. [8] Gestational age, newborn birth weight, and danger presenting risks are all taken into account on whether or not a classic hysterotomy or low transverse incision will be made. [9]

Resuscitative hysterotomy

A resuscitative hysterotomy is performed during or near the occurrence of a cardiac arrest, in which an incision is made to remove the fetus from the uterus. This is done in order to save the fetus, as well as to revive the woman whose uterus was carrying the fetus. This is traditionally done if the fetus is of 24 weeks or older, at which it is viable outside of the uterus. [10] The primary goal is to save the pregnant woman, and in order to insure the highest survival rate, the goal of fetus delivery time is within 5 minutes after the patient goes under arrest and/or two cycles of CPR. [11] During pregnancy, the pregnant uterus may compress the inferior vena cava and abdominal aorta, causing reduced blood flow to the uterus and to the pregnant woman. Removing the fetus can restore blood flow to the pregnant woman. [12]

Fetal surgery

Hysterotomy is a technique used during fetal surgery to access the fetus in the pregnant uterus in order to treat a birth defect such as spina bifida. [13] A standard hysterotomy remains the gold-standard for the closure of a fetal spina bifida because it is the safest and most effective when compared to mini-hysterectomies and a percutaneous two-layer fetoscopy. [14] A mini-hysterotomy procedure is favored for extreme cases of preterm delivery and any complications regarding maternal, fetal, and/or neonatal because of the reduced risks and complications. [15]

Risks and complications

The technique used to repair the hysterotomy is dependent on the surgeon's preference. The method of repair and type of suture affects the risks and complications of receiving a hysterotomy. Hysterotomy incision repair can be done within the intraperitoneal space (in situ) or the uterus can be temporarily removed for repair (exteriorization). Both types of uterine positioning for repair yielded similar lengths of hospital stay, risk of infection, and estimated blood loss. Recovery following uterine exteriorization was found to induce more nausea [16] and be more painful, requiring more post-operative analgesia. Return of bowel function was faster with in situ repair. [17] It was found that between unlocked single-layer closure and double-layer closure, there is no difference in risk of uterine rupture, [3] however the risk of rupture is increased with a locked single-layer suture. [18]

Following the repair of the incision, a scar defect may form, which is defined as a thinning of uterine muscle at the incision site. These uterine scar defects are associated with increased risk of uterine rupture and scar separation. [19] [20] Scar defects may increase the risk of complications such as abnormal bleeding, pain, ectopic pregnancy, and infertility. [3]

During caesarean section

Caesarean sections require a large incision of the uterus, which can lead to complications such as blood loss, postoperative pain, anaemia due to continuing blood loss, fever and possible wound infection, breastfeeding issues, difficulty passing urine, future fertility problems, and/or possible complications in future pregnancies including uterine rupture. [3]

During fetal surgery

In fetal surgery, without inhibition of uterine contractions, uterine irritability and premature labor are complications that occur very frequently in of hysterotomy cases. [21] It can be inhibited by anti-contraction medications. [22] Preterm birth and early membrane rupture (PPROM) are common risks for fetal therapies. For most cases, fetoscopic surgery, which minimizes the damage to the uterus, is preferred to mitigate risks and complications. Membrane sealing and fixation has been investigated for reducing PPROM risk, but it has not been found to be clinically beneficial. [21]

Scar ectopic pregnancy

Scar ectopic pregnancy is a rare form of ectopic pregnancy, however, when it does occur it causes complications in pregnancy such as abnormal uterine bleeding and uterine rupture. The mechanism of how scar ectopic pregnancy still remains unknown. However, the possibility that defects may form to the scarring from previous procedures/traumas such as caesarean section, dilation, hysterotomy, abnormal placentation can cause scar ectopic pregnancy. [4]

Hysterotomy abortion

There are two categories of complications with surgical abortions, minor and major. Minor complications are procedural pain, bleeding, infection and common anesthesia complications. The more serious and major complications include hemorrhage, sepsis, peritonitis, deep vein thrombosis and death. [23]

Types

Location of a low transverse incision and midline vertical incision CesareasHorizontalyVertical.jpg
Location of a low transverse incision and midline vertical incision

There are many different types of hysterotomies depending on the location and direction of the incision. Typically, a low transverse incision is preferred during a caesarean section. This area of the uterus has less vasculature and therefore provides lower risk of hemorrhage during the procedure for the patient. Incisions in the lower area of the uterus is also associated with lower risks of uterine rupture. There may be times in which the lower transverse incision does not provide adequate space and therefore, expansions of the low transverse incisions have led to the creation of the low transverse incision with T-extension in the midline, low transverse incision with J-extension, and low transverse incision with U-extension. [3] A low vertical incision and a midline incision, also known as a classic caesarean incision, may be preferred during a labor that is preterm. Since the lower uterine segment is not yet fully developed during a preterm labor, these two incisions are preferred in order to provide adequate space for manipulations during delivery of the fetus. A low transverse incision would not provide adequate space and could entrap the fetal head therefore risking intercranial hemorrhage, morbidity and mortality for the fetus. [2] A midline incision may be preferred as well when the fetus lies transversely across the patient's uterus or if the placenta lies in the area where the low transverse incision is made. In practice, however, the midline incision is rarely used. [3] Other hysterotomy incisions include a high transverse incision and a fundal incision. [2] A fundal incision may be used if the placenta is placed behind the anterior wall of the uterus and therefore making typical incisions much more risky for hemorrhage. [24]

Techniques

Incision

A hysterotomy can be performed by various methods. Typically a small incision is made with a scalpel about 1–2 cm long. During a blunt expansion, the incision is expanded by the surgeon's index fingers or other blunt dissection tools. During a sharp expansion, bandage scissors are used to cut a larger incision. [25] Some professionals will say that the sharp expansion allows for a more controlled entry into the uterus and a faster delivery of the fetus. Other professionals will say the blunt expansion allows for reduced risk of hemorrhaging or excessive bleeding and improves healing for the patient. [3]

Closure

A hysterotomy is completed by closing the uterus either by using a stapler or by suture, no significant differences have been noted to show one technique takes precedent over another. [5]  The muscular outer layer of the uterus in all samples of closures showed some inflammation and thickening/scarring of the tissue. [26] In the event a midline incision is used, three layers of sutures are performed to repair the uterine wall. An interrupted suture is used to close the first and second layer and a continuous locking suture or figure-of-eight suture is used to close the third layer. [2] Since in practice the low transverse incision is typically made, the incision is also typically closed with two layers of sutures. Though, there is a debate on whether the suture should be close with a single layer or a double layer of sutures. Double layer of sutures can promote improved healing, hemostasis and less risk of uterine rupture in the next pregnancy, whereas single layer of sutures allows for less operation time, less tissue disruption and decreased exposure to foreign suture material. [3]

See also

Related Research Articles

<span class="mw-page-title-main">Caesarean section</span> Surgical procedure in which a baby is delivered through an incision in the mothers abdomen

Caesarean section, also known as C-section or caesarean delivery, is the surgical procedure by which one or more babies are delivered through an incision in the mother's abdomen, often performed because vaginal delivery would put the baby or mother at risk. Reasons for the operation include obstructed labor, twin pregnancy, high blood pressure in the mother, breech birth, shoulder presentation, and problems with the placenta or umbilical cord. A caesarean delivery may be performed based upon the shape of the mother's pelvis or history of a previous C-section. A trial of vaginal birth after C-section may be possible. The World Health Organization recommends that caesarean section be performed only when medically necessary.

<span class="mw-page-title-main">Ectopic pregnancy</span> Female reproductive system health issue

Ectopic pregnancy is a complication of pregnancy in which the embryo attaches outside the uterus. Signs and symptoms classically include abdominal pain and vaginal bleeding, but fewer than 50 percent of affected women have both of these symptoms. The pain may be described as sharp, dull, or crampy. Pain may also spread to the shoulder if bleeding into the abdomen has occurred. Severe bleeding may result in a fast heart rate, fainting, or shock. With very rare exceptions, the fetus is unable to survive.

<span class="mw-page-title-main">Placenta praevia</span> Medical condition

Placenta praevia is when the placenta attaches inside the uterus but in a position near or over the cervical opening. Symptoms include vaginal bleeding in the second half of pregnancy. The bleeding is bright red and tends not to be associated with pain. Complications may include placenta accreta, dangerously low blood pressure, or bleeding after delivery. Complications for the baby may include fetal growth restriction.

<span class="mw-page-title-main">Placental abruption</span> Medical condition

Placental abruption is when the placenta separates early from the uterus, in other words separates before childbirth. It occurs most commonly around 25 weeks of pregnancy. Symptoms may include vaginal bleeding, lower abdominal pain, and dangerously low blood pressure. Complications for the mother can include disseminated intravascular coagulopathy and kidney failure. Complications for the baby can include fetal distress, low birthweight, preterm delivery, and stillbirth.

<span class="mw-page-title-main">Uterine rupture</span> Medical condition

Uterine rupture is when the muscular wall of the uterus tears during pregnancy or childbirth. Symptoms, while classically including increased pain, vaginal bleeding, or a change in contractions, are not always present. Disability or death of the mother or baby may result.

<span class="mw-page-title-main">Uterine myomectomy</span> Surgical removal of uterine fibroid

Myomectomy, sometimes also called fibroidectomy, refers to the surgical removal of uterine leiomyomas, also known as fibroids. In contrast to a hysterectomy, the uterus remains preserved and the woman retains her reproductive potential. It still may impact hormonal regulation and the menstrual cycle.

<span class="mw-page-title-main">Complications of pregnancy</span> Medical condition

Complications of pregnancy are health problems that are related to, or arise during pregnancy. Complications that occur primarily during childbirth are termed obstetric labor complications, and problems that occur primarily after childbirth are termed puerperal disorders. While some complications improve or are fully resolved after pregnancy, some may lead to lasting effects, morbidity, or in the most severe cases, maternal or fetal mortality.

<span class="mw-page-title-main">Placenta accreta spectrum</span> Medical condition

Placenta accreta occurs when all or part of the placenta attaches abnormally to the myometrium. Three grades of abnormal placental attachment are defined according to the depth of attachment and invasion into the muscular layers of the uterus:

  1. Accreta – chorionic villi attached to the myometrium, rather than being restricted within the decidua basalis.
  2. Increta – chorionic villi invaded into the myometrium.
  3. Percreta – chorionic villi invaded through the perimetrium.
<span class="mw-page-title-main">Fetal surgery</span> Growing branch of maternal-fetal medicine

Fetal surgery also known as antenatal surgery, prenatal surgery, is a growing branch of maternal-fetal medicine that covers any of a broad range of surgical techniques that are used to treat congenital abnormalities in fetuses who are still in the pregnant uterus. There are three main types: open fetal surgery, which involves completely opening the uterus to operate on the fetus; minimally invasive fetoscopic surgery, which uses small incisions and is guided by fetoscopy and sonography; and percutaneous fetal therapy, which involves placing a catheter under continuous ultrasound guidance.

<span class="mw-page-title-main">Uterine atony</span> Loss of tone in the uterine musculature

Uterine atony is the failure of the uterus to contract adequately following delivery. Contraction of the uterine muscles during labor compresses the blood vessels and slows flow, which helps prevent hemorrhage and facilitates coagulation. Therefore, a lack of uterine muscle contraction can lead to an acute hemorrhage, as the vasculature is not being sufficiently compressed. Uterine atony is the most common cause of postpartum hemorrhage, which is an emergency and potential cause of fatality. Across the globe, postpartum hemorrhage is among the top five causes of maternal death. Recognition of the warning signs of uterine atony in the setting of extensive postpartum bleeding should initiate interventions aimed at regaining stable uterine contraction.

In case of a previous caesarean section a subsequent pregnancy can be planned beforehand to be delivered by either of the following two main methods:

Tubal reversal, also called tubal sterilization reversal, tubal ligation reversal, or microsurgical tubal reanastomosis, is a surgical procedure that can restore fertility to women after a tubal ligation. By rejoining the separated segments of the fallopian tube, tubal reversal can give women the chance to become pregnant again. In some cases, however, the separated segments cannot actually be reattached to each other. In some cases the remaining segment of tube needs to be re-implanted into the uterus. In other cases, when the end of the tube has been removed, a procedure called a neofimbrioplasty must be performed to recreate a functional end of the tube which can then act like the missing fimbria and retrieve the egg that has been released during ovulation.

<span class="mw-page-title-main">Vaginal delivery</span> Delivery through the vagina

A vaginal delivery is the birth of offspring in mammals through the vagina. It is the most common method of childbirth worldwide. It is considered the preferred method of delivery, with lower morbidity and mortality than Caesarean sections (C-sections).

An asynclitic birth or asynclitism are terms used in obstetrics to refer to childbirth in which there is malposition of the head of the fetus in the uterus, relative to the birth canal. Asynclitic presentation is different from a shoulder presentation, in which the shoulder is presenting first. Many babies enter the pelvis in an asynclitic presentation, and most asynclitism corrects spontaneously as part of the normal birthing process.

<span class="mw-page-title-main">Shoulder presentation</span> Medical condition

A shoulder presentation is a malpresentation at childbirth where the baby is in a transverse lie, thus the leading part is an arm, a shoulder, or the trunk. While a baby can be delivered vaginally when either the head or the feet/buttocks are the leading part, it usually cannot be expected to be delivered successfully with a shoulder presentation unless a cesarean section (C/S) is performed.

<span class="mw-page-title-main">Lower segment Caesarean section</span> Type of caesarean section

A lower (uterine) segment Caesarean section (LSCS) is the most commonly used type of Caesarean section. Most commonly to deliver the baby a transverse incision is made in the lower uterine segment above the attachment of the urinary bladder to the uterus. This type of incision results in less blood loss and is easier to repair than other types of Caesarean sections.

<span class="mw-page-title-main">Interstitial pregnancy</span> Medical condition

An interstitial pregnancy is a uterine but ectopic pregnancy; the pregnancy is located outside the uterine cavity in that part of the fallopian tube that penetrates the muscular layer of the uterus. The term cornual pregnancy is sometimes used as a synonym, but remains ambiguous as it is also applied to indicate the presence of a pregnancy located within the cavity in one of the two upper "horns" of a bicornuate uterus. Interstitial pregnancies have a higher mortality than ectopics in general.

<span class="mw-page-title-main">Prolonged labor</span> Medical condition

Prolonged labor is the inability of a woman to proceed with childbirth upon going into labor. Prolonged labor typically lasts over 20 hours for first time mothers, and over 14 hours for women that have already had children. Failure to progress can take place during two different phases; the latent phase and active phase of labor. The latent phase of labor can be emotionally tiring and cause fatigue, but it typically does not result in further problems. The active phase of labor, on the other hand, if prolonged, can result in long term complications.

<span class="mw-page-title-main">Resuscitative hysterotomy</span>

A resuscitative hysterotomy, also referred to as a perimortem Caesarean section (PMCS) or perimortem Caesarean delivery (PMCD), is a hysterotomy performed to resuscitate a woman in middle to late pregnancy who has entered cardiac arrest. Combined with a laparotomy, the procedure results in a Caesarean section that removes the fetus, thereby abolishing the aortocaval compression caused by the pregnant uterus. This improves the mother's chances of return of spontaneous circulation, and may potentially also deliver a viable neonate. The procedure may be performed by obstetricians, emergency physicians or surgeons depending on the situation.

<span class="mw-page-title-main">Uterine niche</span> A medical disorder of the uterus

A uterine niche, also known as a Cesarean scar defect or an isthmocele, is an indentation of the myometrium at the site of a cesarean section with a depth of at least 2 mm.

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