Skip to main content

Placenta Accreta Facts

Placenta accreta, an abnormally deep attachment of the placenta into the endometrium and myometrium (the middle layer of the uterine wall), complicates 3% of primary, 11% of secondary, 40% of tertiary, 61% of quaternary, and 67% of higher-order cesarean sections for placenta previa.6

The most common risk factor for abnormal placentation is previous cesarean section, but any invasive procedure that might affect the endometrium (including curettage, hysteroscopic surgery, myomectomy, and endometrial ablation) can increase the risk.

Differences in oxygen tension in abnormal placental beds have been invoked as a cause of abnormal placental invasion. It has been reported that preferential implantation of embryos into a relatively avascular scar tissue occurs because of decreased oxygen tension.9

Although the optimal timing for delivery is uncertain, early delivery is often recommended to minimize additional risks that are associated with emergent surgery.

Transcatheter arterial embolization for the control of obstetric hemorrhage has been shown to reduce blood loss and avoid hysterectomy in some cases.

Adequate blood products should be immediately available for transfusion with a rapid infuser. Evidence is now in favor of cell salvage in obstetrics, although this finding remains controversial.18 Recent evidence indicates that preoperative placement

Preoperative placement of ureteral stents is also associated with improved clinical outcome because clear identification of the ureters allows rapid completion of the hysterectomy.

 A vertical midline incision may be considered to achieve optimal visualization.

Many planned cesarean sections for placenta accreta are done with general anesthesia because of concerns for hemodynamic instability and the potential requirement for massive transfusion. However, in a classic study of cesarean hysterectomy at five institutions from the 1980s, 32% of planned cesarean hysterectomies were performed under regional anesthesia. There was no difference in intraoperative blood loss or hypotension, and no one required induction of general anesthesia.

If regional anesthesia is chosen, it is important to counsel the patient and her family about the possibility of conversion to general anesthesia in the setting of massive hemorrhage

Case series heavily populated by placenta accreta often document transfusion requirements of four to six units of pRBCs.

Anesthesiology:
October 2011 - Volume 115 - Issue 4 - p 852–857

Comments

Popular posts from this blog

Driving Pressure in ARDS: A new concept!

Driving Pressure and Survival in the Acute Respiratory Distress Syndrome Marcelo B.P. Amato, M.D., Maureen O. Meade, M.D., Arthur S. Slutsky, M.D., Laurent Brochard, M.D., Eduardo L.V. Costa, M.D., David A. Schoenfeld, Ph.D., Thomas E. Stewart, M.D., Matthias Briel, M.D., Daniel Talmor, M.D., M.P.H., Alain Mercat, M.D., Jean-Christophe M. Richard, M.D., Carlos R.R. Carvalho, M.D., and Roy G. Brower, M.D. N Engl J Med 2015; 372:747-755 February 19, 2015 DOI: 10.1056/NEJMsa1410639 BACKGROUND Mechanical-ventilation strategies that use lower end-inspiratory (plateau) airway pressures, lower tidal volumes (V T ), and higher positive end-expiratory pressures (PEEPs) can improve survival in patients with the acute respiratory distress syndrome (ARDS), but the relative importance of each of these components is uncertain. Because respiratory-system compliance (C RS ) is strongly related to the volume of aerated remaining functional lung during disease (termed functional lung size)...

Anaphylaxis updates part 2- Empty Ventricle Syndrome

Patients with anaphylaxis should not suddenly sit, stand, or be placed in the upright position. Instead, they should be placed on the back with their lower extremities elevated or, if they are experiencing respiratory distress or vomiting, they should be placed in a position of comfort with their lower extremities elevated. This accomplishes 2 therapeutic goals: 1) preservation of fluid in the circulation (the central vascular compartment), an important step in managing distributive shock; and 2) prevention of the empty vena cava/empty ventricle syndrome, which can occur within seconds when patients with anaphylaxis suddenly assume or are placed in an upright position. Patients with this syndrome are at high risk for sudden death. They are unlikely to respond to epinephrine regardless of route of administration, because it does not reach the heart and therefore cannot be circulated throughout the body

Epidural catheter tests...not only the test dose

Siphon test The catheter is held upright and a fluid level sought. If the catheter is then elevated, the fluid level should fall (see inset) as the fluid siphons in to the epidural space, which is usually under negative pressure compared with atmospheric. If the fluid column continues to rise, this may suggest subarachnoid placement. The siphon test can be reassuring, but is not mandatory. Aspiration  This should be considered mandatory. The Luer connector is attached to the catheter and a syringe is used to apply negative pressure. Free and continued aspiration of clear fluid can indicate subarachnoid placement of the catheter. However, if saline has been used for loss of resistance, it is not unusual for a small amount of this to be aspirated. If there is doubt, the aspirated fluid can be tested for glucose (cerebrospinal fluid will generally test positive) or mixed with thiopentone (cerebrospinal fluid forms a precipitate). If blood is freely and continuously aspirated, this sug...