Dilation and Evacuation Case File

Dilation and Evacuation Case File

Eugene C. Toy, MD, Konrad P. Harms, MD, Keith O. Reeves, MD, Cristo Papasakelariou, MD, FACOG

Case 3

A 25-year-old G2P1001 woman at 19 weeks’ gestation presented to the clinic for routine prenatal care. On examination, she was found to have a uterus which was consistent with 18 weeks’ gestation, but no fetal heart tones were heard. An ultrasound was performed and a fetal demise was found with the estimated gestational age of 16 weeks. She denies any vaginal bleeding or uterine cramping. Her cervix is closed on pelvic digital examination. She has no known medical problems and her first pregnancy was a term spontaneous vaginal delivery.

➤ What are your management options?

➤ How might the management affect future pregnancies?

ANSWERS TO CASE 3:

Dilation and Evacuation

Summary: A 25-year-old G2P1001 at 19 weeks’ gestation has an intrauterine demise.

➤ Management options: Dilation and evacuation (D&E) or medical evacuation of the uterus (misoprostol).

➤ Risks for future pregnancies: No increase in clinically significant complications in subsequent pregnancies is anticipated.

ANALYSIS

Objectives

1. Become familiar with management options of second-trimester fetal demise.
2. Review options for cervical dilation.
3. Understand some basic surgical principles of D&E.
4. Understand complications which can occur with a D&E.

Considerations

The management of a second-trimester fetal demise depends on both the clinical expertise of the physician as well as the patient’s desires after counseling. Options for management include medical induction of labor, D&E, hysterotomy, and hysterectomy. Because of the safety, efficiency, and cost-effectiveness of D&E, it has become the most common surgical management of secondtrimester abortions (> 98% of all second-trimester abortions in 2003). A suction D&C is no longer an option after the first trimester, when fetal skeletal parts have begun to calcify, due to a greater risk of complications (uterine perforation, hemorrhage, cervical laceration, and incomplete removal of products). After 15 to 16 weeks’ gestation, a D&E is the preferred method of surgical evacuation of the uterus. Given this patient’s gestation age, she is no longer a candidate for a simple suction D&C. Her management options include either a D&E or medical management (misoprostol). In order to perform a D&E safely, a physician must have specialized training and adequate experience to even offer this treatment plan. The expertise of her physician will dictate which management plan can be performed safely.1

APPROACH TO

Dilation and Evacuation

The technique of a D&E was introduced in the 1970s and is now the preferred surgical technique for second-trimester abortions. After 16 weeks’ gestation, the difference in morbidity and mortality between a D&E and medical management becomes less clear. D&E is more complicated than D&C due to the need for increased cervical dilation, the use of special instruments to remove the fetal parts, assurance that all fetal parts are removed, and the requirement for additional anesthesia. Accurate determination of gestational age is essential as the needed cervical dilation increases with advancing gestational ages. Most forceps require a minimal dilation of 14 to 19 mm. A D&E usually requires either general anesthesia or a paracervical block with conscious sedation. In order to perform a D&E safely, specialized training is a requirement. For physicians with less experience with a D&E, medical management will be their primary treatment option. In a recent Cochrane Database of Systematic Review,2 D&E appears to be associated with fewer overall adverse events, side effects, and pain than induction with medical management. However, medical management (misoprostol and mifepristone) appears to be effective and acceptable. The ideal regimen of misoprostol has not been determined.3,4

Studies have produced conflicting results as to whether the method of cervical dilation is associated with complications of future pregnancy complications such as preterm labor, miscarriage, and cervical incompetence. Cervical trauma from rapid dilation is thought to be the cause of these potential pregnancy complications. Preoperative osmotic dilators are often needed to achieve adequate dilation prior to the D&E. As the gestational age increases, so does the need for cervical dilation. The cervix can be prepared with either osmotic dilators, prostaglandin analogues (misoprostol), or a combination of the two. Osmotic dilators (Figure 3–1) can be made either from natural sources (laminaria made from the stems of seaweed which are dehydrated and made into cervical tents) or synthetic substances (Lamicel or Dilapan). Because laminaria are made from natural sources, the dilation is unpredictable, anaphylaxis has been reported, and it requires time for dilation (often overnight). Each synthetic agent has its own unique properties but, in general, requires less time for dilation as compared to laminaria. Other potential risks of osmotic dilators include vasovagal symptoms with insertion (5%-20%), allergies/anaphylaxis to laminaria, creation of false passage and perforation if placed with force, and theoretic risk of infection (literature does not support an increased risk).5-9

The use of osmotic dilators has been shown to significantly reduce the risk of cervical laceration and trauma to the cervix and reduction in the induction-to-delivery interval.10 In addition, repeated laminaria applications 

Figure 3–1. Osmotic dilators are introduced into the cervical canal, and slowly enlarge as they absorb water. The tip of the dilator should be placed just above the level of the internal os. (Reproduced, with permission, from Schorge JO, Schaffer JI, Halvorson LM, et al. Williams Gynecology. New York: McGraw-Hill, 2008:898.)

have been shown to increase cervical dilation when compared to single application.11 Compared to laminaria, misoprostol alone has been shown to be inferior for cervical dilation. The combination of misoprostol and concurrent placement laminaria often requires only one laminaria application, and thus a shorter time period before procedure can be performed. The combination of laminaria placement with misoprostol has not been shown to increase induction efficiency.12 Proper placement of the laminaria is crucial. The cervix should be cleaned with an antiseptic solution before the laminaria tents are placed through the internal os. After the laminaria have been placed, the use of several saline-soaked gauze sponges in the vagina helps prevent expulsion. Although most practitioners choose to remove the laminaria after 12 hours, laminaria have been noted to continue to expand for up to 24 hours.13 When a patient’s membranes have been ruptured, laminaria should be removed in less than 12 hours and procedure completed. The placement of multiple laminaria is preferred over just one and the number inserted should be recorded in the patient’s record. Care should be taken in placement to not break the dilators, since a fragment in the uterus is problematic and may even require hysterotomy for retrieval.

Between 13 and 16 weeks’ gestation, vacuum extraction with a 14-mm cannula is probably sufficient after adequate cervical dilation. Beyond 16 weeks’ gestation, forcep (Sopher and Bierer) extraction is necessary. These specialized forceps have been found to be superior to standard ring forceps. To minimize perforation risk, the extraction should begin in the lower uterus rather than fundus and continuous ultrasound guidance may aid in the removal of fetal parts. After the cervix is adequately dilated, the large suction cannula is introduced into the uterus and amniotic fluid removed. The surgeon will then extract the fetal parts. At the conclusion of the procedure, the physician must inspect the products and identify all major fetal parts (skull, spine, four extremities) and evaluate the quantity of the placenta.14

Reported complications of D&E include cervical trauma, hemorrhage, perforation of the uterus, infection, and retained products. Intracervical vasopressin (as component of cervical block) has been demonstrated to decrease intraoperative blood loss.15 Intraoperative administration of uterotonic agents (oxytocin or methylergonovine) has been used by some practitioners to minimize blood loss. However, some practitioners prefer not to use these agents because a contracted uterus can make the evacuation more difficult. Recently, there have been case reports published on the use of uterine artery embolization (UAE) to treat hemorrhage from D&E with some success.16 However, it should be noted that UAE should be considered only when the etiology of the bleeding is from an intracervical injury, abnormal placentation, or presence of submucosal fibroids.16 Studies show that very few hysterectomies (11/10,000 or 0.11%) are required due to hemorrhage or other complications in those patients who undergo D&E.4,15,17

Comprehension Questions

3.1 A 23-year-old woman undergoes a D&E after she was found to have an 18-week fetal demise. Which of the following fetal structures is most likely to be left behind in the uterus after a D&E?

A. Calvarium

B. Extremities

C. Abdomen

D. Spine

3.2 Which type of osmotic dilator requires the longest time before maximum cervical dilation?

A. Lamicel

B. Dilapan

C. Laminaria

D. Misoprostol

3.3 A 32-year-old female patient undergoes a D&E for a fetal demise at 16 weeks. Despite adequate dilation of the cervix, all the fetal parts are not able to be removed. What is the most appropriate next step?

A. Give a uterine relaxing agent and proceed with D&E.

B. Proceed with hysterotomy and removal of remaining fetal parts.

C. Expectant management for spontaneous delivery of fetal parts.

D. Administer oxytocin for 2 to 3 hours and attempt repeat D&E.

ANSWERS

3.1 A. The calvarium is the most likely fetal part to be left behind. The use of ultrasound often will help to identify remaining fetal parts. It is imperative for the surgeon to identify all four major body parts prior to concluding the procedure. If the fetal part (most often the calvarium) cannot be removed even under direct ultrasound visualization, oxytocin can be infused for several hours. The remaining fetal part is often closer to the internal os and much easier to remove.

3.2 C. The natural product, laminaria, require a longer period of time before the cervix is maximally dilated (usually overnight). Lamicel, a synthetic agent, works within 2 to 6 hours; however, it does not

achieve as much dilation as other osmotic agents. Dilapan, also a synthetic agent, works within 4 to 6 hours and achieves the greatest cervical dilation within the shortest time frame. The original Dilapan product was removed from the market between 1995 and 2002 due to its increased risk of retained fragments with removal. The newer product has stronger core to decrease this risk. Misoprostol is not an osmotic dilator.

3.3 D. Oxytocin, given intravenously aids in the expulsion of products if D&E is not successful initially. With the combination of ruptured membranes and oxytocin, the remaining fetal parts are often found closer to the cervix and much easier to remove. D&E do not have to be completed in one step. The use of uterine relaxing agent would significantly increase the risk of uterine perforation and hemorrhage and would not be a good option for this patient. Although expectant management would be a possible alternative management strategy, the uncertain time from rupture to delivery of products could possibly increase the risk of infection and therefore is not the best choice. Hysterotomy should only be considered when both surgical and medical managements have failed.

Clinical Pearls

See Table 1-2 for definition of level of evidence and strength of recommendation

➤ The use of osmotic dilators decreases the induction-to-delivery time (Level A).

➤ A D&E has been found to be superior to intrauterine injection with prostaglandin F2α (Level B).

➤ Medical management of second-trimester abortions is as efficacious as a D&E but often with increased pain and side effects (Level B).

➤ The use of osmotic dilators minimizes cervical trauma and decreases the incidence of cervical lacerations and possibly future pregnancy complications (Level B).

➤ In experienced hands,D&E is a more effective and safer treatment compared to medical management, hysterotomy, and hysterectomy (Level C).

➤ Because of the complexity of the procedure and its difficulty as compared to D&C, a D&E procedure should only be performed by practitioners with specialized training (Level C).

REFERENCES

1. Autry AM, Hayes EC, Jacobson GF, Kirby RS. A comparison of medical induction and dilation and evacuation for second-trimester abortion. Am J Obstet Gynecol. 2002;187:393-397. 

2. Lohr PA, Hayes JL, Gemzell-Danielsson K. Surgical versus medical methods for second trimester induced abortion. Cochrane Database Syst Rev. 2008;(1): CD006714. 

3. Cunningham FG, Leveno KJ, Bloom SL, Gilstrap III LC, Wenstrum KD. Abortion. In: Williams Obstetrics. 22nd ed. New York, NY: McGraw-Hill; 2005:241-243. 

4. Gilstrap III LC, Cunningham FG, Vandorsten JP. Pregnancy termination: first and second trimesters. In: Operative Obstetrics. 2nd ed. New York, NY: McGraw-Hill; 2002:540-546. 

5. Turok DK, Curtcheff SE, Esplin MS, et al. Second trimester termination of pregnancy: a review by site and procedure type. Contraception. 2008;77:155-161. 

6. Jackson JE, Grobman WA, Haney E, Casele H. Mid-trimester dilation and evacuation with laminaria does not increase the risk for severe subsequent pregnancy complications. Int J Gynaecol Obstet. 2007;96:12-15. 

7. Kalish RB, Chasen ST, Rosenzweig LB, Rashbaum WK, Chervenak FA. Impact of midtrimester dilation and evacuation on subsequent pregnancy outcome. Am J Obstet Gynecol. 2002;187:613-614. 

8. Lichtenberg ES. Complications of osmotic dilators. Obstet Gynecol Surv. 2004;59:528-535. 

9. Society of Family Planning. Cervical preparation for second-trimester surgical abortion prior to 20 weeks of gestation. Contraception. 2007;76:486-495. 

10. Atlas RO, Lemus J, Reed J, Atkins D, Alger LS. Second trimester abortion using prostaglandin E2 suppositories with or without intracervical laminaria japonica: a randomized study. Obstet Gynecol. 1998;92:398. 

11. Stubblefield PG, Altman AM, Goldstein SP. A randomized trial of one versus two days of laminaria treatment prior to late midtrimester abortion by uterine evacuation: a pilot study. Am J Obstet Gynecol. 1982;143:481. 

12. Jain JK, Mishell DR. A comparison of misoprostol with and without laminaria tents for induction of second trimester abortion. Am J Obstet Gynecol. 1996; 175:173. 

13. Wheeler RG, Scheider K. Properties and safety of cervical dilators. Am J Obstet Gynecol. 1983;146:597. 

14. Chasen ST, Kalish RB, Gupta M, Kaufman JE, Rashbaum WK, Chervenak FA. Dilation and evacuation at ≥ 20 weeks: comparison of operative techniques. Am J Obstet Gynecol. 2004;190:1180-1183. 

15. Peterson WF, Berry FN, Grace MR, Bulbranson CL. Second-trimester abortion by dilation and evacuation: an analysis of 11,747 cases. Obstet Gynecol. 1983;62:185-190. 

16. Haddad L, Delli-Bovi L. Uterine artery embolization to treat hemorrhage following second-trimester abortion by dilatation and surgical evacuation. Contraception. 2009;79:452-455. 

17. Rock J, Jones H. Management of abortion. In: Te Linde’s Operative Gynecology. 10th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008:788-791.

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