Decision making for ongoing management
Once the angles of the hysterotomy have been secured and there are clamps in place to ensure temporary haemostasis it is good practice to call a brief, temporary halt to the procedure and have a whole team (obstetrician, gynae oncologist, 'helicopter', anaesthetic team) discussion as to the best way to proceed. This involves factoring in:
The antenatal imaging findings (important as the neovascularity deep within the pelvis, notably around the cervix, and any parametrial invasion will not be evident before the bladder is reflected)
Current surgical findings including current diagnosis according to FIGO classification
Blood loss to this point and stability of the woman
The stated management preference of the woman (who is usually awake at this point so can be consulted).
After consideration of the entire team (which does not usually take long) the decision will be reached as to whether the plan should be proceeding with focal resection, conservative management or hysterectomy.
Focal resection (uterine conserving surgery)
The IS-AIP evidence based guideline states:
"In appropriately selected cases, local resection appears to be reasonably successful (level 2b evidence) and may reduce blood loss and maternal morbidity compared to hysterectomy (level 2b/4 evidence) and requirement for emergency hysterectomy compared with conservative management (level 3b evidence). Therefore, local resection should be considered in appropriately selected cases (Grade B recommendation).
There is however, some evidence to suggest that attempting local resection may be detrimental in cases involving invasion into the uterine cervix and/or parametrium (level 4 evidence). Therefore, local resection should only be considered where there is no invasion into the parametrium and/or uterine cervix (Grade C recommendation).
The IS-AIP expert consensus of what constitutes an ‘appropriate case’ for local resection is focal disease with an adherent/invasive area which is <50% of the anterior surface of the uterus (Grade D recommendation). "
In keeping with these guidelines the SAC Technique only recommends resection of focal disease which is <50% of the anterior surface of the uterus and not believed to be invading the cervix and/or parametrium on antenatal imaging. This method involves an extirpative method followed by excision of the area of myometrium containing the abnormally invasive placental tissue.
If a focal resection is planned a general anaesthetic is not routinely administered, but only done if the team feels there is a high chance of proceeding to hysterectomy.
If the woman wishes to preserve her fertility and the focal area is low within the lower segment, a foley catheter can be passed through the internal os to demarcate it and ensure it is not inadvertently damaged.
If the woman does not wish to have any further children a bilateral salpingectomy can be offered antenatally (and re-confirmed at the time of surgery).
Expectant (conservative) management
The IS-AIP evidence based guideline states:
"When expectant management is planned and AIP confirmed at delivery, forced manual removal of the placenta should not be attempted (Grade B recommendation).
Expectant management appears to be associated with less blood loss and lower transfusion requirements than both hysterectomy and uterus conserving surgery and will be successful for between 60% to 93% of women with the remainder undergoing hysterectomy, usually for secondary PPH or infection (Grade B recommendation). Therefore, this is an appropriate management strategy for women wishing to preserve their fertility and in cases where hysterectomy is considered to be at very high risk of surgical complications. If women choose this option they must be appropriately counselled including being informed that there is a 6% risk of severe maternal morbidity (Grade B recommendation)."
Deliberate Placental Retention Strategy
In keeping with these guidelines SAC recommends expectant management for women who do not want to have a hysterectomy or where we believe the surgical risks are extremely high. However, there is have a very strict criteria for patient selection for this course of management:
Laparotomy must have confirmed a diffuse, abnormally invasive placenta (we will not offer this for abnormally adherent or only focally invasive placentae).
There must have been no significant antenatal bleeding.
No maternal contraindications to remaining in a 'pregnant' state e.g. significant gestational diabetes requiring insulin.
The woman must be compliant with follow up and able to attend hospital rapidly in an emergency.
She must have been counselled pre-operatively regarding the risks and need for prolonged follow up.
If there is intentional placental retention the following must be done:
Close the uterus in 3 layers (as for a 'classical' incision - she should then be counselled postnatally that she must not labour in future).
Offer bilateral salpingectomy (offered antenatally and re-confirmed at the time).
Having closed the uterus, leave the woman for >30 minutes to ensure there is no bleeding either into the uterus (measure it before and after 30 minutes to ensure it is not increasing in size), into the pelvis or vaginally. Only when it is definitely confirmed that there has not been any blood loss should the expectant management continue.
Close the abdomen as normal.
Give IV antibiotics for 24 hours - then only give as clinically indicated.
Give low molecular weight heparin for 10 days.
Request that the woman take her temperature twice a day and seek help if she develops a raised temperature or any other symptoms of sepsis.
Ensure she has contact details for 24 hour care.
Perform any prophylactic pelvic vessel ligation or embolisation (the extensive neovascularity will reperfused the placental bed within 24 hours therefore if either of these are performed prophylactically the result will be an ischaemic/reperfusion injury to the placental bed increasing the risk of early necrosis with concomitant sepsis and risk of fistula formation).
Give methotrexate. There is no biologically plausible reason that this would hasten placental absorption as after 24 weeks', the placenta is not rapidly dividing tissue, there is no robust evidence that it works and in the single largest case series published, it was the cause of a maternal death.
If proceeding with a hysterectomy this is the point at which the anaesthetic team should administer a general anaesthetic. The surgery then continues as outlined in the next surgical steps.