Step 3: Ultimate management—mobilize and prepare for bleeding
If diagnosis occurs intraoperatively at a PAS specialty center, or if safe transport is not possible, then the team should mobilize for the possibility of hysterectomy and prepare for massive bleeding, which can occur regardless of the treatment chosen. Many patients require or will opt for hysterectomy. For example, a patient who has finished childbearing may consent to a hysterectomy upon hearing she likely has PAS. In patients with suspected PAS who are actively hemorrhaging or are unstable, hysterectomy is required.
Uterine conservation may be considered in stable patients who strongly desire future childbearing or uterine retention. This often requires leaving densely adherent placental tissue in situ and thus requires thorough counseling regarding the risks of delayed hemorrhage, infection, and emergent hysterectomy.11 This may not be desirable or safe for some patients, so informed consent is crucial. In such cases, we strongly recommend consultation with a PAS specialist, even if that requires immediate control of the placental blood supply (such as with arterial embolization), and transfer to a PAS specialty center.
Clinical scenarios
Vaginal delivery
The patient in the opening case was never expected to have PAS given her normal placental location and absence of a uterine scar. Even though she had some possible PAS risk factors (past retained placenta with instrumentation and in vitro fertilization), her absolute risk for the condition was low. Nevertheless, inability to create a separation plane should be considered PAS until proven otherwise. Although at this point many obstetricians would move to an operating room for uterine curettage, we recommend that the care team pause and put measures in place for possible PAS and hemorrhage. This involves notification of the blood bank, crossmatching of blood products, alerting the anesthesia team, and having a clear plan in place should a major hemorrhage ensue. This may involve use of balloon tamponade, activation of an interventional radiology team, or possible laparotomy with arterial ligations or hysterectomy. Avoidance of a prolonged third stage should be balanced against the need for preparation with these cases.
It is important for clinicians to bear in mind, and communicate to the patient, that hysterectomy is the standard of care for PAS. Significant delays in performing an indicated hysterectomy can lead to coagulopathy and patient instability. Timeliness is key; we find that delays in the decision to perform an indicated hysterectomy are often at the root of the cause for worsened morbidity in patients with unanticipated PAS. With an unscarred uterus and no placenta previa, a postpartum hysterectomy can be performed by many obstetrician-gynecologists experienced in this abdominal procedure.
Cesarean delivery
Undiagnosed PAS may present at cesarean delivery with or without placenta previa and a prior uterine scar. With this combination, PAS is often visually apparent upon opening the abdominal cavity (TABLE and FIGURE 1). Such surgical findings call for a clinical pause, as further actions at this point can lead to catastrophic hemorrhage. The obstetrician should consider a series of questions:
1. Are appropriate surgical and transfusion resources immediately available? If yes, they should be notified in case they are needed urgently. If not, then the obstetrician should ask whether the delivery must occur now.
2. Is this a scheduled delivery with a stable patient and fetus? If so, then closing the abdominal incision, monitoring the patient and fetus, and either transferring the patient to a PAS center or awaiting appropriate local specialists may be a lifesaving step.
3. Is immediate delivery required? If the fetus must be delivered, then it is imperative to create a hysterotomy out of the way of the placenta. Disrupting the adherent placenta with either an incision or manual manipulation may trigger a massive hemorrhage and should be avoided. This may require rectus muscle transection or creating a “T” incision on the skin to reach the uterine fundus and creating a hysterotomy over the top or even the back of the uterus. Once the fetus is delivered and lack of uterine hemorrhage confirmed (both abdominally and vaginally), the hysterotomy and abdomen can be closed with anticipation of urgent patient transfer to a PAS team or center.
4. Is the patient hemorrhaging? If the patient is hemorrhaging and closure is not an option, then recruitment of local emergent surgical teams is warranted, even if that requires packing the abdomen until an appropriate surgeon can arrive.
Diagnosis at cesarean delivery requires expedited and complex patient counseling. A patient who is unstable or hemorrhaging needs to be told that hysterectomy is lifesaving in this situation. For patients who are stable, it may be appropriate to close the abdomen and leave the placenta in situ, perform comprehensive counseling, and assess the possibility of transfer to a specialty center.
Summary
All obstetric care providers should be familiar with the clinical presentation of undiagnosed accreta spectrum. While hemorrhage is often part of the diagnosis, recognition of abnormal placental adherence and PAS-focused management should ideally be undertaken before this occurs. Once PAS is suspected, avoidance of further placental disruption may save significant morbidity, even if that means leaving the placenta attached until appropriate resources can be obtained. A local protocol for consultation, emergency transfer, and deployment of local resources should be part of every delivery unit’s emergency preparedness plan.
CASE Outcome
This patient is stabilized, with an adherent, retained placenta and no signs of hemorrhage. You administer uterotonics and notify your anesthesiologist and backup obstetrician that you have a likely case of accreta spectrum. A second intravenous line is placed, and blood products are crossmatched. The closest level III hospital is called, and they accept your patient for transfer. There, she is counseled about PAS, and she expresses no desire for future childbearing. After again confirming no placental separation in the operating room, the patient is moved immediately to perform laparotomy and total abdominal hysterectomy through a Pfannenstiel incision. She does not require a blood transfusion, and the pathology returns with grade I placenta accreta spectrum. ●