Chapter 6 Dilatation and Curettage of the Nonpregnant Uterus. Operative Techniques

 Chapter 6 Dilatation and Curettage of the Nonpregnant Uterus

GENERAL PRINCIPLES

Definition

■ Dilatation and curettage, commonly called D&C, is the sampling of the uterine endometrial lining and contents of the uterine cavity. Dilatation, or dilation, refers to the opening of the cervical canal which is the portal into the uterine cavity. Curettage is the scraping of the endometrial lining of the uterine cavity.

Differential Diagnosis

■ Abnormal uterine bleeding, perimenopausal bleeding, postmenopausal bleeding, fibroids, endocervical or endometrial polyps, cervical cancer, endometrial hyperplasia, uterine cancer, pyometra, hematometra, retained products of conception.

Anatomic Considerations

■ In cases of Mullerian defects, such as uterus didelphys, bicornuate uterus, or septate uterus, D&C should be performed under ultrasound guidance.

Nonoperative Management

■ IPAS is a double-valve manual vacuum aspiration syringe that can be used in the office, obviating the operating room.1 The World Health Organization has approved its use for endometrial sampling in the setting of abnormal uterine bleeding.

IMAGING AND OTHER DIAGNOSTICS

■ Pelvic ultrasound and/or saline-infused sonogram characterize the uterine contour, endometrium, intracavitary polyps and fibroid, as well as intramural, subserosal, and submucosal fibroids. Furthermore, the classic heterogeneous pattern of adenomyosis may be recognized.

■ In rare cases, MRI may be used to detect the presence of Müllerian defects such as unicornuate uterus, uterus didelphys, bicornuate uterus, or septate uterus.

PREOPERATIVE PLANNING

■ A complete history and physical examination is necessary to rule outpregnancy, to determine the ease or difficulty of uterine access, to illicit any medical comorbidities that will affect anesthesia, and to determine coagulation risks.

■ Cervical stenosis prevents the passage of a 2.5-mm Pratt dilator. Stenosis can be anticipated if there is a history of prior cervical or uterine procedures such as a LEEP or cone biopsy, routine biopsies, cryotherapy, laser surgery, or endometrial ablation. It can result from lack of vaginal deliveries, infection, or estrogen deficiency.

■ Treat cervical stenosis with preoperative Misoprostol 400 mcg, oral or sublingual, 12 hours prior to D&C. Various regimens have been recommended and may facilitate cervical access.2,3 Alternatively, laminaria are osmotic dilators that can soften and dilate the cervix in order to prevent uterine perforation during the dilatation process. They are placed in the office at least 12 to 24 hours before the D&C is performed and removed intraoperatively.

SURGICAL MANAGEMENT

Positioning

■ The patient is placed in the lithotomy position with her legs in candy cane or Allen stirrups. Be careful not to hyperflex the hips or hyperextend the knees (Fig. 6.1).

Approach

Perform a pelvic examination, carefully sound the uterus, serially dilate the cervix, and then systematically scrape the uterine lining. If there is a high suspicion for the presence of uterine polyps, a polypectomy should be done before the curettage. If endometrial carcinoma is highly suspected, a fractional curettage is performed. Tissue is first obtained from the endocervical canal. Then, the endometrial canal is sampled. This is done in order to avoid contamination of the sites.

Figure 6.1. Lithotomy position. Hyperflexion of the hip and hyperextension of the knee are avoided to prevent injury of the femoral nerve and lumbosacral trunk.

Perform pelvic examination prior to the procedure. It is imperative to determine whether the uterus is anteflexed or retroflexed to avoid uterine perforation. The degree of flexion is also important to note. Pratt or Hank dilators have the advantage of having tapered shank which accommodate the flexion of the uterus so that the instrument will not perforate a severely retroflexed or anteflexed uterus.Procedures and Techniques

Visualize cervix

■ After the patient has been prepped and draped in sterile fashion, place a weighted speculum posteriorly under the cervix and use a right-angle or singlebladed retractor to elevate the anterior vaginal wall (Tech Fig. 6.1).

Tech Figure 6.1. Surgical instruments used in D&C: A: weighted speculum; B: sidewall retractors; C: Pratt dilators; D: Sharp curettes; E: Serrated curette; F: Duncan,

rectangular curette; G: Uterine sound; H: Single-tooth tenaculum; I: Jacobs doubletooth tenaculum; J: IPAS; K: Laminaria.

Stabilize the cervix

■ Grasp the anterior lip of the cervix with a single-tooth tenaculum.

Sound the uterus

■ Gently sound the uterus with a Sims-graduated ball tip uterine sound.

Dilate the cervix

■ Serially dilate the cervix using dilators.

Endometrial polypectomy

■ In order not to miss an endometrial polyp, make a systematic sweep of the uterine lining with a ureteral stone forceps.

Uterine curettage

■ Using a Heaney serrated curette, the uterine cavity is systematically scraped. In an anteflexed uterus, start at the 12-o’-clock position and scrape along the anterior uterine wall from the fundus toward the cervix. This motion is repeated in a clockwise fashion. It is better to start at the fundus and pull toward yourself rather than to scrape back and forth. As the tissue extrudes from the cervix, collect it in a spoon or directly onto a piece of Telfa that has been placed in the posterior fornix (Tech Fig. 6.2).

■ If cancer is suspected, perform an endocervical curettage using a Duncan rectangular curette before performing the uterine curettage. The entire length of the cervix, from the internal os to the external os, is scraped. Send the tissue specimens to pathology separately.

Tech Figure 6.2. Uterine curettage. The curette is gently advanced to the uterine fundus. Circumferentially, starting at 12 o’-clock, the sharp edge is brought forward toward the internal cervical os.

PEARLS AND PITFALLS

Cervical stenosis: In addition to preprocedure misoprostol treatment and laminaria, intraoperative dilute vasopressin solution may be injected into cervical stroma using 10 cc of solution.

Avoid overdilatation: Dilate just enough to accommodate the instruments needed. If hysteroscopy is to be performed, overdilatation will result in poor uterine distension as the hysteroscopic medium leaks out. If this occurs, the cervix may be tightened around the hysteroscope by clamping the cervix with a ring forceps or tenaculum or by placing a suture through the cervical tissue.

Cervical laceration: A single-tooth tenaculum can lacerate the cervical tissue causing bleeding and will not give you the necessary traction. Use a heavier tenaculum such as a Jacobs double-tooth tenaculum and take care to note the bladder margin at the anterior cervix.

Avoid creating a false passage: Start with the largest curette that easily penetrates the cervix. Avoid very small dilators such as lacrimal duct dilators, as these instruments can be pushed through almost any tissue leading you to falsely believe that you have entered the uterine cavity.

Avoid uterine perforation: When dilating the cervix, do not apply excessive force.

Hold dilators with your fingertips and not against the palm of your hand. When sounding the uterus, advance the sound slowly until resistance at the fundus is encountered.

Asherman syndrome: Avoid aggressive curettage in a recently pregnant or infected uterus. A Foley balloon can be placed in the uterine cavity to prevent adhesion of the uterine walls. Remove 10 days after the procedure. Doxycycline 100 mg twice daily for 10 days is given concomitantly to prevent infection.

POSTOPERATIVE CARE

■ Monitor the patient for bleeding, pain, and anesthesia complication in the PACU. Mild cramping and light spotting are to be expected for a few days. To avoid infection, nothing should be placed inside the vagina until menses resume or cleared by their physician. Patients are also instructed to avoid bathtub soaking, swimming, intercourse, and tampon usage for 14 days.

COMPLICATIONS

■ The overall complication rate for D&C is less than 2%. Independent risk factors for D&C complication include retroverted uterus, postmenopausal status, and nulliparity.5

■ Possible complications include uterine perforation; damage to internal organs such as bowel, bladder, ureters, major blood vessels; endometritis;hemorrhage; vaginal laceration; cervical laceration; pelvic pain; creation of a false passage; and Asherman syndrome. If uterine perforation is suspected, the surgeon must thoroughly evaluate the pelvic cavity to assess for additional injury. If the patient is hemodynamically stable and the surgeon is proficient in laparoscopy, a diagnostic laparoscopy is the preferred approach. The perforation should be examined to assess the entire extent of the injury/laceration, and the pneumoperitoneum should be decreased to 5 mm Hg and observed for several minutes. 

A hemodynamically stable uterine perforation requires no further surgical intervention. The patient should be informed of the complication and counseled on concerning signs and symptoms that should prompt medical care. If the perforation site is bleeding, the surgeon may utilize combination of suture, coagulation, or fulguration to achieve hemostasis. A thorough pelvic and vasculature survey must include a complete bowel evaluation. If the patient is hemodynamically unstable, surgical discretion is advised. A frank and clear discussion between the surgeon and anesthesiology team should include risks and benefits of exploratory laparotomy versus medical stabilization prior to laparotomy