Video Clip on DVD
- 12-1
Operative Hysteroscopic Myomectomy
Despite increasing medical and surgical options, the number of hysterectomies in the past decade has not decreased. Hysterectomy remains the second most common operative procedure performed in women only superseded by cesarean delivery. In 2003, the Nationwide Inpatient Sample of the Healthcare Cost and Utilization Project reported 538,722 hysterectomies were performed for benign conditions. Only 10% of hysterectomies were performed for genital malignancy. The most common indications for hysterectomy included uterine fibroids (33%) and menstrual disorders (17%). Approximately 5.8 hysterectomies per 1000 U.S. females are performed annually. Regional variations in hysterectomy are also reported; the highest rates of hysterectomy in the United States occur within the southern states and the lowest rates are in the western part of the country.
Hysterectomy for benign disorders has a number of drawbacks, not the least of which is an overall complication rate of 17% to 23%, regardless of approach—abdominal, transvaginal, laparoscopic, or robotic. Hysterectomy is not appropriate for women who wish to retain their fertility; moreover, the procedure may have a significant negative impact on psychosexual health.
Even though hysterectomy unequivocally solves fibroid-related symptoms (abnormal bleeding, dysmenorrhea, pelvic pain, leukorrhea, and bulk symptoms), increasingly patients and physicians are seeking alternatives to hysterectomy for the treatment of fibroids and menstrual disturbances. Open or laparoscopic myomectomy is a well-established alternative in select women. What other alternatives exist? The first report in 1995 demonstrated the benefits of uterine fibroid embolization (UFE) for the treatment of fibroid-related symptoms. The introduction of the operative hysteroscope has permitted treatment of intracavitary leiomyomas and polyps. There are women with abnormal bleeding and a normal uterine cavity or with intramural fibroids (<3 cm) that do not distort the endometrial cavity who may benefit from endometrial ablation. MRI-focused ultrasound also offers a subset of women with symptomatic uterine fibroids another treatment option. Recently, the Food and Drug Administration (FDA) approved the progesterone intrauterine system for heavy menstrual bleeding in women who also need contraception. Clinical reports of excellent efficacy outcomes demonstrate superior improvements in menorrhagia, abnormal uterine bleeding, and dysmenorrhea.
Physicians managing patients with uterine fibroids and abnormal bleeding must comprehend the risks and benefits of each of these treatment modalities. Future fertility is an important factor in determining the appropriateness or exclusion for many of these alternatives. A patient’s ultimate choice among available fibroid therapies may depend upon the fibroid-related impact on her health-related quality of life (HRQOL), the length of convalescence that is acceptable to her, and the importance she assigns to tolerable invasiveness and symptom resolution.
Medical Management with Levonorgestrel-Releasing Intrauterine System
Case Presentation
A 33-year-old gravida 4, para 2, aborta 2 presents with a history of gradually developing menorrhagia without anemia. She describes regular menses during which she passes large clots. At the peak of her bleeding, these symptoms require changing her pad and tampon every 3 hours. Pad changes as well as soiling of her clothes interfere with her daily activities at work and home during her menses. She underwent sonohysterography with findings of a 9-cm uterus with a 2-cm intramural myoma and no intracavitary lesions. Her hematocrit and Papanicolaou (Pap) smear are normal. She relates that she and her husband would like to have another child and asks what her options are to control her heavy bleeding.
Indications
Newer safety data on the use of contemporary intrauterine systems (IUS) and the relaxation of eligibility criteria have expanded use of these devices for both contraceptive and noncontraceptive benefits. The progestin-impregnated IUS was introduced in the 1970s to increase contraceptive efficacy and reduce expulsion rates by decreasing uterine contractility. The progestin exerts a local suppressive effect on the endometrium rendering it unresponsive to the proliferative effects of estrogen. This results in a reduction in the number of days of bleeding and progressive decrease in mean blood loss, sometimes to amenorrhea. Owing to these endometrial effects, use for noncontraceptive benefits is increasing, although this does represent off-label usage. The use of the levonorgestrel-releasing intrauterine system (LNG-IUS) in women with fibroids is somewhat controversial, but the available data support its use in women with fibroids that do not distort the uterine cavity.
Patient Selection
Prior to recommending an IUS for control of menorrhagia a thorough interview is necessary to establish the patient’s preference for medical management. The advantages and disadvantages of LNG-IUS are shown in Table 12-1 . Often desire for future fertility plays a large role in the patient’s decision. A complete medical and surgical history with a specific focus on gynecologic and obstetric events must be obtained to ensure that the patient is an appropriate candidate. A long history of menorrhagia as well as nongynecologic bleeding episodes may prompt evaluation for hematologic disorders, most commonly von Willebrand disease. Subsequently, a physical examination is needed to evaluate for any concerns, especially those relating specifically to IUS placement, such as cervical stenosis and the presence of fibroids. Transvaginal ultrasound or sonohysterography may be needed for further evaluation of the uterine cavity if fibroids are suspected. Irregular bleeding patterns may require an endometrial biopsy. Routine screening for sexually transmitted infections is not supported by available evidence but may be appropriate in a high-risk patient. Documentation of a current normal Pap smear is also prudent. Thorough and effective patient counseling to dispel common myths and ensure appropriate expectations for the IUS can serve to increase acceptance among patients.
Advantages | Disadvantages |
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Per current American College of Obstetrics and Gynecology (ACOG) guidelines, contraindications for IUS use include current pregnancy, current or recent pelvic inflammatory disease, current cervicitis, current or recent postpartum endometritis or infected abortion, undiagnosed abnormal uterine bleeding, known or suspected genital tract malignancy, allergy to any component of the IUS, and known uterine anomalies or fibroids that distort the uterine cavity in a way incompatible with IUS insertion. The package insert for the LNG-IUS currently marketed in the United States includes additional restrictions such as untreated bacterial vaginitis; acute liver disease or liver tumor; history of multiple sexual partners in the woman or her partner; increased susceptibility to infections, leukemia, acquired immune deficiency syndrome (AIDS) and intravenous (IV) drug abuse; genital actinomycosis; a previously inserted IUS that has not been removed; known or suspected carcinoma of the breast; or a history of ectopic pregnancy or condition that would predispose to ectopic pregnancy. Even though many of these contraindications appear reasonable, most are not directly described in the literature. Use of the IUS in nulliparas may be associated with an increased rate of expulsion but is not contraindicated; however, cervical dilation may be required.
Use of the IUS may reduce symptoms and therefore reduce the rate of diagnosis of fibroids. Comparison of various case series describing both success and failure of the LNG-IUS in ameliorating menorrhagia in women with fibroids reveals that outcomes in these patients may be dependent on overall uterine dimensions, fibroid size, and size of the uterine cavity. Studies have shown decreased mean blood loss with type II fibroids, meaning intramural fibroids that may have a submucosal component. Use of the IUS does not routinely result in decreased fibroid or uterine size and expulsion is more common with cavity-distorting fibroids. The World Health Organization (WHO) criteria state that insertion of the IUS in women with cavity-distorting fibroids who desire contraception represents an unacceptable risk.
Insertion Techniques
After the appropriate evaluation and discussion, informed consent and a negative pregnancy test on the day of the procedure must be obtained. Product brochures and replacement reminder cards should be given to the patient.
Product packaging for the LNG-IUS recommends placement during menses to avoid insertion with unknown pregnancy. Timing the insertion on day 5 to 7 may result in easier passage; however, the IUS can be inserted at any time in the cycle that pregnancy can be excluded. Misoprostol has been shown to aid insertion, but the effect of this medication on expulsion rate is not known.
A bimanual examination prior to insertion can aid placement by assessing uterine size and position.
Lower pain scores have been noted with the use of 2% intracervical lidocaine gel. Many practitioners advise patients to pretreatment with nonsteroidal anti-inflammatory drugs (NSAIDs) prior to insertion or they perform a paracervical block, but there are no data on efficacy of these types of analgesia.
Aseptic techniques should be followed throughout insertion and after placement of a vaginal speculum. The cervix should be cleansed.
A tenaculum is used to grasp the anterior lip of the cervix and the uterus sounded to determine patency of the endocervical canal and internal os. Placement of the tenaculum on the posterior lip may be more helpful if the uterus is retroflexed. In some women, especially nulliparous or perimenopausal, the sound cannot be passed and cervical dilation may be necessary. The uterus should sound within 6 to 10 cm and the product should not be placed into a cavity that is less than 6 cm. If no intracavitary assessment has been performed, sweeping the sound laterally at the fundus has been advocated to assess the feasibility of high fundal placement. In patients with a markedly retroverted uterus, placement under ultrasound guidance can be helpful to decrease perforation and ensure correct placement.
The IUS package should only be opened after these preparatory steps have been completed to decrease costs related to an unused but opened IUS. The IUS then is loaded into the insertion tube and the IUS threads secured. The IUS flange is set to the sounded depth. The loaded insertion tube is then advanced into the uterine cavity until it is 1.5 to 2 cm from the fundus. The IUS arms are then deployed and the IUS is advanced gently to the fundus. The insertion tube is gently retracted without pulling on the IUS strings. The strings are cut to 3 cm in length, taking care not to cut at an angle and may be tucked under the cervix to minimize partner discomfort during intercourse.
After insertion, the need for analgesia is assessed and the patient is counseled on expected bleeding patterns over the next several months. She is instructed to watch for signs of expulsion, pregnancy, and infection. Re-evaluation of string placement after 4 to 12 weeks should be scheduled, at which time the strings may be trimmed if needed. She is also instructed on how to check the strings herself. The patient should be advised to call with any concerns including bleeding, abnormal discharge, pelvic pain, fever, or painful intercourse.
Complications
Difficulties that can occur during IUS insertion include vasovagal reaction, cervical stenosis requiring dilation, failed insertion, or uterine perforation. Uterine perforation occurs in less than 0.5% of women. This risk may be increased in postpartum and lactating women and may be minimized by proper insertion technique. Suspected uterine perforation must be confirmed by ultrasound and the IUS removed by laparoscopy; rarely is laparotomy required. Expulsion can occur in up to 5% of patients and is increased in nulliparas and with postpartum or postabortal insertion. Occasionally the IUS is noted to be present in the cervix on physical examination or ultrasound. Advancing the IUS can be attempted with caution but the procedure should be abandoned if not easily completed. Following advancement, a pelvic ultrasound should be ordered with an additional string check following the next menses.
Early studies showing a link between IUS use and pelvic inflammatory disease (PID) are now thought to be flawed. PID infections are now thought to be rare among IUS users although there has been some increase in those with active infection at the time of placement or within the first 30 days. Prophylactic antibiotics are not currently recommended but could be considered in a high-risk patient. Current data show no effect on parameters such as hypertension, glucose control, or lipids aside from possible increase in high-density lipoproteins (HDLs), although more studies are needed.
Pregnancy rates with the IUS are similar for perfect and typical use with 5-year failure rates less than 0.5%. Pregnancy rates can be minimized by high fundal placement with subsequent decrease in partial or complete expulsion. The overall pregnancy rate remains extremely low; however, the relative rate of spontaneous abortion and ectopic pregnancy are increased. No specific congenital anomalies are associated with pregnancies with an IUS in place. Preterm delivery is more common under these circumstances.
Outcomes
Early discontinuation rates are highly linked to menstrual abnormalities and this decision may be tempered by counseling for realistic expectations prior to placement. Additional side effects are usually mild but can include weight gain, bloating, acne or oily skin, nausea, and breast pain. The first studies describing the use of the LNG-IUS for menorrhagia were performed in the 1980s. Since then the device has been shown to control bleeding more effectively than other medical regimens including hormonal treatments, prostaglandin inhibitors, antifibrinolytic agents, and nonsteroidal medications such as mefenemic acid. Although bleeding patterns in the first 4 to 6 months may be variable, overall bleeding can decrease by up to 90%. At 1 year of use, 20% of women experience complete amenorrhea. The rate of amenorrhea increases to 50% to 75% in women with menorrhagia, and in anemic women hemoglobin rises by 2 to 3 g/dL at 1 year. Cost analysis reveals that the LNG-IUS is less expensive than other medical regimens, possibly due to decreased need for surgical management of bleeding, and results in increased quality-adjusted life-years. The use of the LNG-IUS in women with known bleeding disorders also results in decreased blood loss and the device may have the same effect in women with adenomyosis.
Transcervical endometrial ablation has been compared to the LNG-IUS and results in greater initial decrease in blood loss, but similar rates at 3 years with comparable patient satisfaction. Additionally, placement of the IUS after global ablation can further improve bleeding profiles. Although post-ablation placement may be theoretically logical, it represents off-label usage. Also, the development of intense fibrosis and Asherman syndrome after ablation may make the IUS difficult to remove. When the LNG-IUS was provided to women on the waiting list for hysterectomy because of menstrual dysfunction, at 6 months 64.3% of women had canceled their surgery and at 12 months 47% still continued its use. Five-year follow-up results from a randomized controlled trial of the LNG-IUS compared to hysterectomy revealed comparable improvement in quality of life, with 48% of women indicated continued use. Expenses related to hysterectomy were noted to be three times higher and the IUS was felt to be a cost-effective alternative to hysterectomy in the first year of use. Additional benefits of the LNG-IUS include retained fertility and no requirement for operative skills or surgical facilities.
Many studies have included dysmenorrhea as a secondary outcome with improvement in pain scores after IUS insertion. One study noted improvement in endometriosis staging after IUS insertion. The device is also under evaluation in clinical studies for the prevention of endometrial hyperplasia. Use of the LNG-IUS in high-risk women with known uterine cancer has been described in case reports. Thus, the LNG-IUS represents an effective office-based intervention to the patient with menorrhagia, although limited in its scope by the extent of uterine disease.
Hysteroscopic Myomectomy
Case Presentation
J.B. is a 51-year-old, gravida 7, para 6 who recently noted changes in her menstrual cycles. Previously her cycles were every 28 to 30 days and lasted 4 to 5 days. She changed her menstrual products (pads or tampons) three to four times daily. She did not have dysmenorrhea and her menstrual cycles did not interfere with her lifestyle. Within the past 6 to 9 months, her cycles are still monthly, but last for 8 to 10 days, requiring her to change her menstrual products every 1 to 2 hours, with night-time changing, soiling through clothing, and avoiding travel, sports, and leisurely activities during her cycles. On examination, her uterine size felt normal without adnexal masses. Recent laboratory findings included a normal Pap test and negative human papillomavirus (HPV) test. Anemia was detected: hemoglobin 8.0 g/dL and hematocrit 27%, normal platelet count. Her thyroid-stimulating hormone (TSH) level was normal. Saline infusion sonography revealed a posterior 3.3 cm intracavitary leiomyoma ( Fig. 12-1 ). She was scheduled for operative hysteroscopic myomectomy.
Discussion of Case
The desire of many women to retain their uterus and return to normal activities quickly prompted the emergence of less invasive technologies for the treatment of symptomatic fibroids. In the early 1980s, the urologic resectoscope was first used to remove intrauterine polyps and fibroids. The development of a continuous flow hysteroscope resectoscope permitted distention of the uterine cavity with fluid and removal of blood and debris ( Fig. 12-2 ). Ancillary wire loops, scissors, morcellators, and vaporizing electrodes permit numerous procedures ( Fig. 12-3 ). Resectoscopy permits removal of endometrial polyps, submucosal fibroids, targeted and directed endometrial biopsy, division of uterine septa, and endometrial ablation. Further improvements in optics, video recording, and intrauterine distention systems provided additional safety features for operative hysteroscopic procedures.
Operative hysteroscopic myomectomy requires an understanding of fluid management; good hand–eye coordination; sound judgment about when to abandon the hysteroscopic approach; and a thorough preoperative evaluation including a detailed knowledge of the number, size, location, and depth of myometrial involvement of the fibroids.
Preoperative Evaluation
Preoperative evaluation of the uterine cavity is important to determine the size, number, location, and depth of penetration of the leiomyoma. These factors will determine the surgical expertise necessary, risks, and surgical complications, as well as the ability to complete the procedure in one surgical setting. Most important, these factors determine whether a hysteroscopic surgical approach is indicated. Patient selection criteria for operative hysteroscopy are shown in Table 12-2 .
Indications for Operative Hysteroscopy | Contraindications to Operative Hysteroscopy |
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There is no hysteroscopic classification system that is uniformly accepted. However, and agree that the depth of myometrial involvement determines the degree of difficulty, surgical expertise, and risks of fluid overload. The European Society of Gynaecological Endoscopy (ESGE) classification considers only the degree of myometrial penetration, which is determined hysteroscopically. Type G0 myomas are completely within the endometrial cavity; type G1 myomas extend less than 50% into the myometrium; and type G2 have more than 50% of their volume within the myometrium. The ESGE system is derived hysteroscopically and therefore depth of myometrial involvement is subjectively obtained and may be influenced by intrauterine distending media and pressure.
The ESGE classification system recommends that resection of leiomyoma be limited to type 0 and type 1 myomas, unless a surgeon has expert hysteroscopic skills. Although the ESGE does not specify a size limitation, the physician should be aware of increasing complexity of surgery when the fibroid is greater than 4 to 5 cm. Limited operative views, narrower surgical spaces, and the accumulation of large leiomyoma chips can lead to increased operative time and subsequent volume overload. Increased physician experience is required in these cases to safely and successfully navigate hysteroscopic myomectomy.
The choice of anesthesia—local, regional, or general—depends upon many factors, such as surgeon’s preference, patient’s medical status, type and complexity of the procedure, facility capabilities, and patient preference.
Procedure for Hysteroscopic Myomectomy
Prior to hysteroscopy, inspection of the vulva and bimanual examination is necessary to determine uterine position and to exclude adnexal or pelvic tenderness. Knowledge of the uterine position will help orient placement of the hysteroscope and decrease the risk of uterine perforation. After the speculum is inserted, the cervix is visualized and then cleansed with an antiseptic solution. Hysteroscopy should not be performed in the presence of mucopurulent cervicitis, pelvic inflammatory disease, or herpetic infections.
Vaginoscopic or no-touch technique has increasingly has been advocated. Without use of a speculum, the hysteroscope is introduced in the lower vagina and cervix. Proponents advocate its use because it is associated with less pain, and decreases the need for premedication, analgesia, or anesthesia when used in office diagnostic hysteroscopy. It can also be used during operative hysteroscopy.
In the absence of infection, the distal end of hysteroscope is inserted into the cervix and panoramic inspection of the endocervix performed. The hysteroscope should be advanced under direct inspection with distention medium and without undue force into the uterine cavity. Once inside the uterine cavity the topography of the endometrial cavity and tubal ostia is assessed. When fluid is used for uterine distention, the maximal pressure is 100 mm Hg. Ideally the intrauterine pressure should be maintained at less than the mean arterial pressure. However, if higher pressures are needed for visualization, close monitoring of the fluid deficit is necessary.
The operative resectoscope is an adaptation of the urologic resectoscope, with the added ability to provide continuous circulation of fluid. The continuous flow mechanism clears debris and mucus, permitting excellent visualization throughout the surgical procedure.
Hysteroscopic myomectomy is commonly performed using a resectoscope. Currently there are four hysteroscopic methods to remove intracavitary leiomyoma: wire loop resection, vaporizing electrode, hysteroscopic morcellator, and scissors. Once inside the endocervix, the exact location of the lesion(s) should be determined, the uterotubal ostia visualized, and size of the lesion(s) confirmed. These maneuvers map out the surgical procedure to provide the safest operative strategy for hysteroscopic removal. When multiple lesions are encountered, removal of the lesions nearest the cervix and posterior wall is advised, followed by resection of more fundal and lateral lesions.
The basic resection technique involves serial slicing or shaving of a lesion until it is flush with the endometrium ( Fig. 12-4 ). The wire loop (monopolar or bipolar) is placed behind the lesion and drawn toward the physician when the electrode is activated. Cutting begins at the surface, with the trajectory always directed toward the operator, keeping the loop visible at all times. With each passage of the wire loop, crescent-shaped pieces of tissue will float into the uterine cavity. When visualization is obscured, the accumulated fibroid pieces should be removed with the wire loop, Corson graspers, or polyp forceps. When tissue chips are removed blindly, care must be taken to prevent uterine perforation. Although fibroid chips may pass spontaneously, leaving them within the uterus may result in colicky pain, persistent leukorrhea, adhesions, or intrauterine infection. Furthermore, pathologic examination of the tissue is essential. (See DVD Video 12-1 for video demonstration of Hysteroscopic Myomectomy. )
Additional Techniques
Fibroids may have a myometrial attachment. Full enucleation requires expert hysteroscopic skills and identification of the surgical planes. To facilitate removal, intermittent uterine decompression, manual massage, injection of prostaglandin F 2α , and wire loop mechanical resection techniques have been described. The use of preoperative Cytotec 200 to 400 µg, orally or vaginally taken at bedtime prior to hysteroscopic myomectomy, facilitates cervical dilation and may increase uterine contractions to assist in the enucleation of leiomyomas.
A variety of cutting and coagulating loops, barrels, or balls are available. Monopolar and bipolar operative hysteroscopes are currently available. When a monopolar operative hysteroscope is used, a dispersive pad must be placed on the patient and a nonelectrolyte, nonconducting, distending medium such as 1.5% glycine, 3% sorbitol, or 5% mannitol must be used. With a bipolar device, saline or Ringer lactate is used and the patient does not need a dispersive pad.
Recently, a Hysteroscopic Morcellation System (Smith & Nephew, Andover, MA) and MyoSure Tissue Removal System (Interlace Medical, Framingham, MA) were introduced that resect intracavitary lesions without electrical energy and utilizes saline as the distending medium. A recent modification of the traditional hysteroresectoscope, the Chip E-Vac system (Richard Wolf Corp., Vernon Hills, IL) is currently available in the United States as a bipolar system, and permits rapid resection of intracavitary lesions. The added benefit is that the resected fibroid “chips” are suctioned through the hysteroscopic sheath. This adaptation is beneficial because it reduces the number of fibroid “chips” within the uterine cavity, decreases the frequency of needing to remove the hysteroscope for fibroid chip retrieval, and keeps the operating field clear of debris. Additionally, saline is used as the distention medium. Most hysteroscopic sheaths have an outer diameter of 7 to 10 mm and include both inflow and outflow ports for distending media.
Historically, grasping forceps, such as Leahy clamps or Corson graspers, have been placed within the uterine cavity and in the hopes that blind grasping of an intracavitary lesion would lead to avulsion technique and retrieval of tissue. If this method is chosen, it is important to look hysteroscopically after attempts at blind retrieval have been undertaken to decrease the chances of incomplete removal or remnants of tissue left in situ. Blind attempts at grasping intracavitary lesions also can be associated with uterine perforation, bowel injury, or uterine inversion.
Targeted endometrial biopsies are indicated when focal lesions are noted. The endometrial surface may have focal irregularities, polypoid projections, and discrete lesions. Using the wire loop, hysteroscopic targeted biopsies with complete removal of lesions may be obtained and sent for histologic analysis.
Among women wishing to preserve fertility, some gynecologists empirically prescribe high-dose estrogen to aid in re-epithelization of the endometrium with the aim of decreasing the risk of intrauterine adhesions after hysteroscopic myomectomy. Typically, conjugated estrogen 1.25 daily or estradiol 1 mg twice daily is given for 30 days, followed by 12 days of progesterone (i.e., norethindrone 5 mg or medroxyprogesterone 10 mg). Alternatively, a pediatric Foley catheter, inflated with 5 to 10 mL of normal saline or sterile water is inserted for 7 to 10 days to prevent the juxtaposition of the uterine walls. If an indwelling pediatric is placed, prophylactic use of doxycycline 100 mg orally twice daily until the catheter is removed is advised. Repeat office hysteroscopy is performed within 7 to 14 days following extensive myomectomy to evaluate the endometrium for synechiae. We advocate office flexible hysteroscopy when the pediatric foley is removed. If detected early, the adhesions are filmy and easily lysed with the distal tip of a hysteroscope.
Electrocautery and Laser
Specially adapted loop electrodes, roller balls, and vaporizing electrodes can be used to resect, desiccate, or ablate endometrial tissue. When monopolar electrodes are used, a cutting current of 60 W to 100 W is utilized. When bipolar electrical energy is utilized the default settings are applied. Generally speaking wire loop resection is performed for procedures such as polypectomy, submucous resection, and endomyometrial resection ablation. Rollerballs are used for hysteroscopic endometrial ablation. The neodymium:yttrium-aluminum-garnet (Nd:YAG), argon, and potassium titanyl phosphate (KTP) lasers can be used for hysteroscopic surgery. Lasers can be used to perform endometrial ablation, lysis of adhesions, or desiccation of intracavitary lesions. Lasers are more expensive to maintain, require additional nursing and surgeon training, and have little advantage over electrosurgical resection techniques.
Distention Media
General Principles
The endometrial cavity is a potential space. It must be distended with fluid or CO 2 . Operative hysteroscopy is generally performed with fluid. The type of electrical energy utilized determines the selection of fluids. Monopolar energy requires hypotonic, low-viscosity fluids such as glycine 1.5%, sorbitol 3%, or mannitol 5%. Bipolar energy requires isotonic solutions such as normal saline or Ringer lactate. Glycine, a low-viscosity fluid, is used with monopolar electrocautery because it is a poor electrical conductor, minimizes hemolysis during irrigation, and provides excellent optical images. If electrolytic solutions are inadvertently used during monopolar resectoscopy, there is diffusion of electrical current and the wire loop will not cut.
During hysteroscopy, the major mechanism of fluid loss is through systemic intravascular absorption. Very little fluid is lost via the fallopian tubes. When excessive absorption of electrolyte-free solution occurs systemically, hyponatremia may ensue. When the serum sodium level declines, there is an increase in the hypotonic solutes from the distention media causing a decline in serum osmolality. Glycine is a nonessential amino acid and is metabolized in the liver and kidney by oxidative deamination via glycine oxidase to ammonia and glycolic acid. Encephalopathy occurs as a result of ammonia toxicity. In the midbrain, spinal cord, and ganglion cells in the retina, glycine has an inhibitory effect. Transient blindness may be due to these mechanisms. The greatest risk of morbidity and mortality in operative hysteroscopy is due to fluid overload. Clinical symptoms from hyponatremia can occur when the serum sodium levels are below 120 mmol/L. Postoperatively, signs of hyponatremia include nervous system agitation, nausea, vomiting, headache, blurred vision, and seizures.
Factors that increase the risk of fluid intravasation include excessive intrauterine pressure, resection of large fibroids, prolonged operative times, deep myometrial resection, resection of septa, and treatment of Asherman syndrome. Close attention to fluid deficits are advised. Electronic fluid pumps or a dedicated nurse who calculates input and output are imperative for patient safety.
Bipolar energy requires normal saline or Ringer lactate. Isotonic solutions, by virtue of their serum osmolality and sodium content, prevent the development of hyponatremia and hypo-osmolality. The use of isotonic solutions does not decrease the risk of excessive intravasation. Excessive intravascular absorption of saline can be associated with congestive heart failure and pulmonary edema. Avoidance of preoperative overhydration and minimal intravenous hydration should be communicated with the anesthesiologist when complicated cases are anticipated.
Fluid Management
Fluid management systems (fluid pumps) play a vital role in the safety of operative hysteroscopy. Many fluid management systems are available; patient safety is increased when guidelines for managing fluid absorption are followed. These pumps provide an automated system with minute-to-minute calculation of inflow and calculation of the fluid deficit. The physician can preset the allowable fluid deficit, based on the patient’s risk factors (age, cardiovascular reserve, and renal function). Automatic audible alerts will alert the surgeon when the maximal fluid deficit has been reached. An additional advantage to the fluid pump is the ability to determine intrauterine pressure and to easily adjust fluid pressures to control bleeding and decrease “false negative” views of the endometrial cavity that may occur with higher or constant endometrial pressure. Alternating the intrauterine fluid pressure may also help facilitate full resection of uterine fibroids by causing myometrial contraction, which helps enucleate the myoma. Automated fluid pumps are essential in modern operative hysteroscopy. Less desirable is the technique of elevating the bags above the patient and infusing by the force of gravity or placed in a large blood pressure cuff and infused by pressurizing the cuff. Because fluid can rapidly and unpredictably be absorbed, continuous deficit monitoring is essential. If fluid pumps are not available, a nurse dedicated to calculating the I/O’s every 5 to 10 minutes is necessary.
Complications
Patients generally have minimal postoperative pain following hysteroscopic myomectomy. A serosanguinous discharge for 1 to 4 weeks is typical following the procedure. Mild cramping is easily alleviated with low-dose NSAIDs, and a few patients require narcotics for postoperative pain management. Patients typically resume normal activities within 24 to 48 hours after the procedure. Sexual activity can be resumed 1 week postoperatively. If an incomplete resection has occurred, some patients may pass pieces of fibroid tissue several weeks after the procedure or complain of leukorrhea and cramping.
Common intraoperative complications of resectoscopic surgery include uterine perforation and absorption of distending medium. Two ancillary medications, vasopressin and misoprostol, may decrease the risks associated with operative hysteroscopy. The most common complication of operative hysteroscopy is uterine perforation. Cervical stenosis and deep myometrial resection increase the risk of perforation and fluid absorption. A prospective double-blind study and randomized clinical trial demonstrated the benefits of dilute vasopressin ( ). Vasopressin decreases fluid absorption, decreases blood loss, decreases fluid intravasation, and induces smooth muscle contractions of the uterine capillaries, small arterioles, and venules. Its use is advocated when prolonged surgery, larger lesions, or deeper myometrial resection is anticipated, or when cervical stenosis is encountered.
To decrease the risk of uterine perforation due to cervical stenosis and difficult cervical dilation, misoprostol may be considered. Misoprostol is a prostaglandin PGE 1 analog used for cervical ripening. Misoprostol increases intracellular accumulation of free water, softens the cervix, and passively increases the diameter of the cervical os. These factors combined lead to easier cervical dilation, decreased risk of cervical lacerations, uterine perforation, and creation of false tracks during dilation. Various routes (oral, vaginal, rectal, and sublingual), dosages, and times of administration have been advocated. Alternatively a laminaria tent can be inserted the day before the surgical procedure.
Patients with postoperative fever, malaise, worsening pain, or escalating pain medication requirements should be carefully evaluated for bowel injury, bladder injury, and endometritis. Office evaluation must be undertaken including thorough abdominal and pelvic examination. Laboratory testing including electrolytes, complete blood count (CBC), sedimentation rate, ultrasound, and flat plate of the abdomen (kidney, ureter, bladder [KUB]/upright film) may be required, depending upon the clinical scenario. Sometimes a computed tomography (CT) scan of the pelvis/abdomen may be needed if perforation with bowel or bladder injury is suspected.
Conclusions
Patients now have an array of options available for the treatment of symptomatic uterine fibroids. Hysteroscopic myomectomy is a well-established treatment for women with hysteroscopically resectable uterine fibroids. Preoperative evaluation is essential to the success of the procedure. Appropriately triaged patients have excellent outcome, low morbidity rate, and resolution of menstrual aberrations. Additionally, intraoperative hysteroscopic techniques to facilitate complete removal and close attention to fluid management provide optimal safety and improved clinical outcome.
Endometrial Ablation
Case Presentation
A 41-year-old gravida 4, para 3 female reports a long history of heavy regular periods without associated dysmenorrhea. Her past medical history is notable for multiple deep venous thromboses (DVT) and she is now on lifelong anticoagulation. Her past surgical history is significant for one prior cesarean section with tubal ligation. On examination, she is not obese and has a normal 10-week size anteverted uterus. On saline infusion sonography, she is noted to have a 10-cm uterus with a single 2-cm submucus fibroid. Evaluation of her prior lower uterine segment uterine scar reveals normal thickness (>10 mm) in this area. She denies symptomatic pelvic organ prolapse or incontinence. Previous attempts to manage her bleeding included Depo-Provera, that caused irregular bleeding, and a Mirena Intrauterine Device (Bayer Health Care Pharmaceuticals, Montville, NJ), was declined by the patient. Recent endometrial biopsy and cervical cytologic findings are normal. She would like to avoid hysterectomy if possible due to her history of DVT and use of anticoagulation.