Extended Hysterectomy for Selected Cases of Placenta Accreta

Technique of Complex Hysterectomy

General anesthesia is preferred, due to the potential for rapid hemorrhage requiring prompt surgical control. The patient is placed in a low lithotomy position. This allows ready access to the perineum and an additional surgeon at the operative field (Fig. 2A). The laparotomy incision should be placed to enable a high hysterotomy and subsequent exposure above the enlarged uterus as well as to the deeper regions of the pelvis. Initially, the scarred pelvic portion of the incision is left undissected in order to mitigate damage and placental trauma and to expedite delivery.

OPEN IN VIEWER

FIG. 2.

(A) Patient positioned in lithotomy and prepared for complicated cesarean hysterectomy. CVP, central venous pressure. (1) High fundal cesarean section to avoid placenta. (2) Hysterotomy was closed. Division of round ligaments. (3) Ureters are isolated at the pelvic brim and mobilized toward the ureteric tunnels. (4) The utero-ovarian pedicles are stapled. (5) The posterior leaf of the broad ligament is divided, joining the previous ureteral dissection. The ureters are further mobilized. (6) The upper parauterine attachments are divided. (7) The uterine vessels are transected adjacent to the uterus outside the plane of any placental tissue. (8) The bladder is separated away from the cervix if there is a clear plane from the placenta. The cardinal ligaments are divided adjacent to the expanded lower uterine segment/cervix outside the plane of any placental tissue. (9) The uterosacral ligaments are divided (in energy device is being utilized here). (B) Superior view of bladder resection. (10) Placenta percreta with invasion of the bladder. (11) Cesarean hysterectomy with resection of the infiltrated portion of the bladder.

Limited data suggest that ureteral stents help avoid ureteral injury in the management of high-risk cases of placenta accreta. ¹ It is hazardous to dissect the ureters from the markedly vascular parametria. Although ureteral stents do not always prevent ureteral injury, it is easier to recognize. Furthermore, it has been the current authors' experience that frequent palpation of the stents during hysterectomy precludes the necessity for more extensive dissection. Placement of the stents prior to delivery is more controlled but could require an additional anesthetic. The stents may be placed while the cesarean section is being performed or just after delivery. The bladder is inspected for the presence and location of placental invasion.

It is imperative that the hysterotomy incision avoids the placenta, and this generally requires a fundal incision; its placement may be aided by a preincision ultrasound scan (Fig. 2A1). Delivery of the neonate should be accomplished without manually disturbing the placenta. Manual delivery of the placenta should be avoided (Supplementary Video S1; Supplementary Data are available online at www.liebertpub.com/gyn).

If needed to obtain hemostasis, the uterine incision may be closed with a single layer of #2 polypropylene running-locked suture or approximated with towel clamps that may be used later for traction.

Most women with placenta accreta will have undergone prior cesarean sections, and extensive scarring of the lower uterus segment and adhesions of the anterior cul-de-sac to the abdominal wall are common. Dissecting the retropubic space and skirting lateral to the bladder avoids injury to the bladder and affords the maximum deep pelvic exposure. A self-retaining retractor is then placed, and the sigmoid colon and cecum are mobilized to enable packing that will maximize pelvic exposure.

Great care is taken to maintain tight control of the vascular pedicles, and to avoid any transgression into placental tissue and/or maneuvers such as excessive traction or rocking the uterus anteriorly that could fracture the placenta.

The round ligaments are divided lateral to the utero-ovarian vascular anastomoses and dissected toward the uterus (Fig. 2A–2). The ureters are isolated at the pelvic brim above the uterus and held with vessel loops (Fig. 2A–3). After locating an avascular window under the utero-ovarian ligament, the utero-ovarian pedicle is divided (Fig 2A–4). A vascular stapler may be used, due to the length and highly vascular nature of the pedicle and the proximity of the ovary, as well as for control of back-bleeding. Obviously, familiarity with this device and the various sizes of staple loads is required.

The posterior leaves of the broad ligaments are incised, taking great care to skirt the uterine vasculature. These incisions are extended across the posterior peritoneal reflection to meet the isolated ureters (Fig. 2A-5). The ureters are mobilized laterally carefully until the ureteric tunnels are reached. Typically, long Kelley clamps are placed tightly against the uterine fundus for the purposes of traction and control of back-bleeding.

The anterior leaves of the broad ligament are divided toward the reflection of the bladder. Typically, the broad ligaments are elongated and largely avascular, and can be divided with cautery dissection (Fig. 2A-6). In most cases, the bladder may be mobilized cautiously from the lower uterine segment and cervix. At this juncture, a bladder that is densely adherent or attached immediately over apparent placental tissue can be encountered. In such cases, it is prudent to delay any attempt to separate the bladder until additional uterine devascularization is accomplished and the boundaries of the bladder scar and/or placental invasion are defined better.

When the bladder is dissected out of harm's way, the uterine vessels are then divided against the uterus (Fig. 2A-7). Again, the use of a vascular stapler could have some advantages over the standard clamp-and-ligature technique. Due to the markedly expanded lower uterine segment, the ureters will be in close proximity (the stented ureter can usually be palpated). For this reason and for hemostatic control, it is important to keep the stapler or clamp tightly against the uterus—but in the “extra fascial plane” so as to avoid disruption of the placenta. A useful maneuver to accomplish all of these goals is (with slight upward and contralateral traction on the uterus) to grasp the lateral tissue to be divided with the thumb and forefinger, pinching immediately adjacent to the uterus so that all of the urinary tract–bearing tissue is pulled laterally and the pedicle is made “tight.” At the same time, the tips of these fingers push the stapler (or clamp) firmly against the uterus, adjusting the angle as appropriate. Division of the cardinal ligament is similarly carried to the cervicovaginal junction (Fig. 2A-8). It is often helpful to divide the uterosacral ligaments seperately to isolate and devascularize the uterus (Fig. 2A–9) more completely. Delineation by pressure with a sponge stick in the vagina is useful.

The cervicovaginal junction is then transected and the vaginal cuff is closed hemostatically with a running-lock suture or with a roticulating stapler that fires an absorbable load of staples across the vagina.

Following removal of the uterus, a substantial volume of “raw” pelvic floor remains and might contribute to postoperative hemorrhage. At least partial reperitonealization (over hemostatic agents if deemed necessary) that incorporates vascular pedicles cautiously and the closed vaginal cuff may help prevent this event. A closed suction drain is placed at the discretion of the surgeon.

Placenta Percreta with Bladder Invasion

Placenta percreta with bladder invasion deserves special comment. This condition might be suspected preoperatively (based on imaging and, occasionally, hematuria) and/or intraoperatively (cystoscopy and/or gross invasion of placenta into the bladder muscularis). When the diagnosis is suspected and the placenta appears to be encroaching on the bladder muscularis, the surgeon should assume that placenta percreta is present. In selected cases (e.g., anticipated loss of a large portion of the bladder, unusual surgical difficulty) consideration is given to leaving the placenta in place. ¹⁰ Attempts to separate the bladder from the uterus and cervix in this instance (even in the absence of overt bladder invasion) could result in massive hemorrhage.

Placenta percreta usually involves the lower uterine segment and the mid-posterior dome of the bladder (Fig. 2B-10). It is important to devascularize as much of the uterus as possible before approaching this region and to avoid traction or any other type of trauma to this region until it is planned. It is almost always possible to open an avascular space (medial to the umbilical ligaments) bilaterally that separates the bladder from the parametrial and paracervical tissues. To a limited extent, the ureters will be mobilized laterally with this maneuver but will still potentially be in harm's way (especially distally). Following development of these spaces, the uterine vessel pedicles are stapled just lateral to the uterine–placental mass. The uterosacral ligaments are defined and divided (a bipolar energy device works well here) just outside the margin of the cervix–placental mass as described above. If ureteral stents are in place and the surgeon can develop the space between the paracervical tissues and the urinary tract confidently, then these ligaments are stapled as well. Blunt digital dissection of the bladder from cervix caudal to the area of adherence is often possible, ⁴ and transection of the vaginal fornix at this point can be considered (with a stapler if it can be isolated or, alternatively, approached through the posterior vaginal wall).

Because the surgeon is able to get more distal in the progress of the hysterectomy, approaching the adherent urinary tract becomes safer and defined better. Surgical management of the adherent, vascular region of the urinary tract can then proceed as indicated by the gross findings and judgment of the surgeon (i.e., separation versus resection). If there is loss of a clear plane of separation between a deeply invading placenta and the bladder, the surgeon must err on the side of leaving detrusor muscle or a full thickness disc of bladder transected to the uterine specimen.

Next, the surgeon should approach the unscarred spaces on either side (or potentially caudal to) of the region of bladder involvement, transect the distal paracervical tissues, and enter into the bladder immediately cephalad to the invaded (or densely adherent) portion (Fig 2B-11a,b). The surgeon is then in a position to resect only the well-delineated (and usually disc-shaped) segment of involved bladder (Fig. 2B-11b). The cesarean hysterectomy is then completed, followed by repair of the bladder.