Surgical Techniques

 

 

CASE Concerning finding on repeat CD

A 30-year-old woman with a history of 1 prior cesarean delivery (CD) presents to labor and delivery at 38 weeks of gestation with symptoms of mild cramping. Her prenatal care was uncomplicated. The covering team made a decision to proceed with a repeat CD. A Pfannenstiel incision is made to enter the abdomen, and inspection of the lower uterine segment is concerning for a placenta accreta spectrum (PAS) (FIGURE).

What would be your next steps?

 

Placenta accreta spectrum describes the range of disorders of placental implantation, including placenta accreta, increta, and percreta. PAS is a significant cause of severe maternal morbidity and mortality, primarily due to massive hemorrhage at the time of delivery. The incidence of PAS continues to rise along with the CD rate. The authors of a recent meta-analysis reported a pooled prevalence rate of 1 in 588 women.¹ Notably, in women with PAS, the rate of hysterectomy is 52.2%, and the transfusion-dependent hemorrhage rate is 46.9%.¹

Ideally, PAS should be diagnosed or at least suspected antenatally during prenatal ultrasonography, leading to delivery planning by a multidisciplinary team.² The presence of a multidisciplinary team—in addition to the primary obstetric and surgical teams—composed of experienced anesthesiologists, a blood bank able to respond to massive transfusion needs, critical care specialists, and interventional radiologists is associated with improved outcomes.^3-5

Occasionally, a patient is found to have an advanced PAS (increta or percreta) at the time of delivery. In these situations, it is paramount that the appropriate resources be assembled as expeditiously as possible to optimize maternal outcomes. Surgical management can be challenging even for experienced pelvic surgeons, and appropriate resuscitation cannot be provided by a single anesthesiologist working alone. A cavalier attitude of proceeding with the delivery “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences, including maternal death.

In this article, we review the important steps to take when faced with the unexpected situation of a PAS at the time of CD.

 

Continue to: Stop and collect your multidisciplinary team...

 

Stop and collect your multidisciplinary team

Once the diagnosis of an advanced PAS is suspected, the first step is to stop and request the presence of your institution’s multidisciplinary surgical team. This team typically includes a maternal-fetal specialist or, if not available, an experienced obstetrician, and an expert pelvic surgeon, which varies by institution (gynecologic oncologist, trauma surgeon, urologist, urogynecologist, vascular surgeon). An interventional radiology team is an additional useful resource that can assist with the control of pelvic hemorrhage using embolization techniques.

In our opinion, it is not appropriate to have a surgical backup team available only as needed at a certain distance from the hospital or even in the building. Because of the acuity and magnitude of bleeding that can occur in a short time, the most appropriate approach is to have your surgical team scrubbed and ready to assist or take over the procedure immediately if indicated.

Additional support staff also may be required. A single circulating nurse may not be sufficient, and available nursing staff may need to be called. The surgical technician scrubbed on the case may be familiar only with uncomplicated CDs and can be overwhelmed during a PAS case. Having a more experienced surgical technologist can optimize the availability of the appropriate instruments for the surgical team.

If a multidisciplinary surgical team with PAS management expertise is not available at your institution and the patient is stable, it is appropriate to consider transferring her to the nearest center that can meet the high-risk needs of this situation.⁶

Prepare for resuscitation

While you are calling your multidisciplinary team members, implement plans for resuscitation by notifying the anesthesiologist about the PAS findings. This will allow the gathering of needed resources that may include calling on additional anesthesiologists with experience in high-risk obstetrics, trauma, or critical care.

Placing large-bore intravenous lines or a central line to allow rapid transfusion is essential. Strongly consider inserting an arterial line for hemodynamic monitoring and intraoperative blood draws to monitor blood loss, blood gases, electrolytes, and coagulation parameters, which can guide resuscitative efforts and replacement therapies.

Simultaneously, inform the blood bank to prepare blood and blood products for possible activation of a massive transfusion protocol. It is imperative to have the products available in the operating room (OR) prior to proceeding with the surgery. Our current practice is to have 10 units of packed red blood cells and fresh frozen plasma available in the OR for all our prenatally diagnosed electively planned PAS cases.

Optimize exposure of the surgical field

Appropriate exposure of the surgical field is essential and should include exposure of the uterine fundus and the pelvic sidewalls. The uterine incision should avoid the placenta; typically it is placed at the level of the uterine fundus. Exposure of the pelvic sidewalls is needed to open the retroperitoneum and identify the ureter and the iliac vessels.

Vertical extension of the fascial incision probably will be needed to achieve appropriate exposure. Although at times this can be done without a concomitant vertical skin incision, often an inverted T incision is required. Be mindful that PAS is a life-threatening condition and that aesthetics are not a priority. After extending the fascial incision, adequate exposure can be achieved with any of the commonly used retractors or wound protectors (depending on institutional availability and surgeon preference) or by the surgical assistants using body wall retractors.

We routinely place the patient in lithotomy position. This allows us to monitor for vaginal bleeding (often a site of unrecognized massive hemorrhage) during the surgery, facilitate retrograde bladder filling, and provide a vaginal access to the pelvis. In addition, the lithotomy position allows for cystoscopy and placement of ureteral stents, which can be performed before starting the surgery to help prevent urinary tract injuries or at the end of the procedure in case one is suspected.⁷

 

Continue to: Performing the hysterectomy...

 

 

 

Performing the hysterectomy

A complete review of all surgical techniques for managing PAS is beyond the scope of this article. However, we briefly cover important procedural steps and offer suggestions on how to minimize the risk of bleeding.

In our experience. The areas with the highest risk of massive bleeding that can be difficult to control include the pelvic sidewall when there is lateral extension of the PAS, the vesicouterine space, and placenta previa vaginally. Be mindful of these areas at risk and have a plan in place in case of bleeding.

Uterine incision

Avoid the placenta when making the uterine incision, which is typically done in the fundal part of the uterus. Cut and tie the cord and return it to the uterine cavity. Close the incision in a single layer. Use of a surgical stapler can be used for the hysterotomy and can decrease the amount of blood loss.⁸

Superior attachments of the uterus

The superior attachments of the uterus include the round ligament, the utero-ovarian ligament, and the fallopian tubes. With meticulous dissection, develop an avascular space underneath these structures and, in turn, individually divide and suture ligate; this is typically achieved with minimal blood loss.

In addition, isolate the engorged veins of the broad ligament and divide them in a similar fashion.

In our experience. Use of a vessel-sealing device can facilitate division of all the former structures. Simply excise the fallopian tubes with the vessel-sealing device either at this time or after the uterus is removed.

Pelvic sidewall

Once the superior attachments of the uterus have been divided, the next step involves exposing the pelvic sidewall structures, that is, the ureter and the pelvic vessels. Expose the ureter from the pelvic brim to the level of the uterine artery. The hypogastric artery is exposed as well in this process and the pararectal space developed.

When the PAS has extended laterally, perform stepwise division of the lateral attachments of the placenta to the pelvic sidewall using a combination of electrocautery, hemoclips, and the vessel-sealing device. In laterally extended PAS cases, it often is necessary to divide the uterine artery either at its origin or at the level of the ureter to allow for the completion of the separation of the placenta from the pelvic sidewall.

In our experience. During this lateral dissection, significant bleeding may be encountered from the neovascular network that has developed in the pelvic sidewall. The bleeding may be diffuse and difficult to control with the methods described above. In this situation, we have found that placing hemostatic agents in this area and packing the sidewall with laparotomy pads can achieve hemostasis in most cases, thus allowing the surgery to proceed.

Continue to: Bladder dissection...

 

Bladder dissection

The next critical part of the surgery involves developing the vesicovaginal space to mobilize the bladder. Prior to initiating the bladder dissection, we routinely retrograde fill the bladder with 180 to 240 mL of saline mixed with methylene blue. This delineates the superior edge of the bladder and indicates the appropriate level to start the dissection. Then slowly develop the vesicouterine space using a combination of electrocautery and a vessel-sealing device until the bladder is mobilized to the level of the anterior vaginal wall. Many vascular connections are encountered at that level, and meticulous dissection and patience is required to systematically divide them all.

In our experience. This part of the surgery presents several challenges. The bladder wall may be invaded by the placenta, which will lead to an increased risk of bleeding and cystotomy during the dissection. In these cases, it might be preferable to create an intentional cystotomy to guide the dissection; at times, a limited excision of the involved bladder wall may be required. In other cases, even in the absence of bladder wall invasion, the bladder may be densely adherent to the uterine wall (usually due to a history of prior CDs), and bladder mobilization may be complicated by bleeding from the neovascular network that has developed between the placenta and bladder.

Uterine arteries and cervix

Once the placenta is separated from its lateral attachments and the bladder is mobilized, the next steps are similar to those in a standard abdominal hysterectomy. If the uterine arteries were not yet divided during the pelvic sidewall dissection, they are clamped, divided, and suture ligated at the level of the uterine isthmus. The decision whether to perform a supracervical or total hysterectomy depends on the level of cervical involvement by the placenta, surgeon preference, anatomic distortion, and bleeding from the cervix and anterior vaginal wall.

Responding to massive bleeding

Not uncommonly, and despite the best efforts to avoid it, massive bleeding may develop from the areas at risk as noted above. If the bleeding is significant and originates from multiple areas (including vaginal bleeding from placenta previa), we recommend proceeding with an expeditious hysterectomy to remove the specimen, and then reassess the pelvic field for hemostatic control and any organ damage that may have occurred.

The challenge of PAS

Surgical management of PAS is one the most challenging procedures in pelvic surgery. Successful outcomes require a multidisciplinary team approach and an experienced team dedicated to the management of this condition.⁹ By contrast, proceeding “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences in terms of maternal morbidity and mortality. ●

 

 

CASE Concerning finding on repeat CD

A 30-year-old woman with a history of 1 prior cesarean delivery (CD) presents to labor and delivery at 38 weeks of gestation with symptoms of mild cramping. Her prenatal care was uncomplicated. The covering team made a decision to proceed with a repeat CD. A Pfannenstiel incision is made to enter the abdomen, and inspection of the lower uterine segment is concerning for a placenta accreta spectrum (PAS) (FIGURE).

What would be your next steps?

 

Placenta accreta spectrum describes the range of disorders of placental implantation, including placenta accreta, increta, and percreta. PAS is a significant cause of severe maternal morbidity and mortality, primarily due to massive hemorrhage at the time of delivery. The incidence of PAS continues to rise along with the CD rate. The authors of a recent meta-analysis reported a pooled prevalence rate of 1 in 588 women.¹ Notably, in women with PAS, the rate of hysterectomy is 52.2%, and the transfusion-dependent hemorrhage rate is 46.9%.¹

Ideally, PAS should be diagnosed or at least suspected antenatally during prenatal ultrasonography, leading to delivery planning by a multidisciplinary team.² The presence of a multidisciplinary team—in addition to the primary obstetric and surgical teams—composed of experienced anesthesiologists, a blood bank able to respond to massive transfusion needs, critical care specialists, and interventional radiologists is associated with improved outcomes.^3-5

Occasionally, a patient is found to have an advanced PAS (increta or percreta) at the time of delivery. In these situations, it is paramount that the appropriate resources be assembled as expeditiously as possible to optimize maternal outcomes. Surgical management can be challenging even for experienced pelvic surgeons, and appropriate resuscitation cannot be provided by a single anesthesiologist working alone. A cavalier attitude of proceeding with the delivery “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences, including maternal death.

In this article, we review the important steps to take when faced with the unexpected situation of a PAS at the time of CD.

 

Continue to: Stop and collect your multidisciplinary team...

 

Stop and collect your multidisciplinary team

Once the diagnosis of an advanced PAS is suspected, the first step is to stop and request the presence of your institution’s multidisciplinary surgical team. This team typically includes a maternal-fetal specialist or, if not available, an experienced obstetrician, and an expert pelvic surgeon, which varies by institution (gynecologic oncologist, trauma surgeon, urologist, urogynecologist, vascular surgeon). An interventional radiology team is an additional useful resource that can assist with the control of pelvic hemorrhage using embolization techniques.

In our opinion, it is not appropriate to have a surgical backup team available only as needed at a certain distance from the hospital or even in the building. Because of the acuity and magnitude of bleeding that can occur in a short time, the most appropriate approach is to have your surgical team scrubbed and ready to assist or take over the procedure immediately if indicated.

Additional support staff also may be required. A single circulating nurse may not be sufficient, and available nursing staff may need to be called. The surgical technician scrubbed on the case may be familiar only with uncomplicated CDs and can be overwhelmed during a PAS case. Having a more experienced surgical technologist can optimize the availability of the appropriate instruments for the surgical team.

If a multidisciplinary surgical team with PAS management expertise is not available at your institution and the patient is stable, it is appropriate to consider transferring her to the nearest center that can meet the high-risk needs of this situation.⁶

Prepare for resuscitation

While you are calling your multidisciplinary team members, implement plans for resuscitation by notifying the anesthesiologist about the PAS findings. This will allow the gathering of needed resources that may include calling on additional anesthesiologists with experience in high-risk obstetrics, trauma, or critical care.

Placing large-bore intravenous lines or a central line to allow rapid transfusion is essential. Strongly consider inserting an arterial line for hemodynamic monitoring and intraoperative blood draws to monitor blood loss, blood gases, electrolytes, and coagulation parameters, which can guide resuscitative efforts and replacement therapies.

Simultaneously, inform the blood bank to prepare blood and blood products for possible activation of a massive transfusion protocol. It is imperative to have the products available in the operating room (OR) prior to proceeding with the surgery. Our current practice is to have 10 units of packed red blood cells and fresh frozen plasma available in the OR for all our prenatally diagnosed electively planned PAS cases.

Optimize exposure of the surgical field

Appropriate exposure of the surgical field is essential and should include exposure of the uterine fundus and the pelvic sidewalls. The uterine incision should avoid the placenta; typically it is placed at the level of the uterine fundus. Exposure of the pelvic sidewalls is needed to open the retroperitoneum and identify the ureter and the iliac vessels.

Vertical extension of the fascial incision probably will be needed to achieve appropriate exposure. Although at times this can be done without a concomitant vertical skin incision, often an inverted T incision is required. Be mindful that PAS is a life-threatening condition and that aesthetics are not a priority. After extending the fascial incision, adequate exposure can be achieved with any of the commonly used retractors or wound protectors (depending on institutional availability and surgeon preference) or by the surgical assistants using body wall retractors.

We routinely place the patient in lithotomy position. This allows us to monitor for vaginal bleeding (often a site of unrecognized massive hemorrhage) during the surgery, facilitate retrograde bladder filling, and provide a vaginal access to the pelvis. In addition, the lithotomy position allows for cystoscopy and placement of ureteral stents, which can be performed before starting the surgery to help prevent urinary tract injuries or at the end of the procedure in case one is suspected.⁷

 

Continue to: Performing the hysterectomy...

 

 

 

Performing the hysterectomy

A complete review of all surgical techniques for managing PAS is beyond the scope of this article. However, we briefly cover important procedural steps and offer suggestions on how to minimize the risk of bleeding.

In our experience. The areas with the highest risk of massive bleeding that can be difficult to control include the pelvic sidewall when there is lateral extension of the PAS, the vesicouterine space, and placenta previa vaginally. Be mindful of these areas at risk and have a plan in place in case of bleeding.

Uterine incision

Avoid the placenta when making the uterine incision, which is typically done in the fundal part of the uterus. Cut and tie the cord and return it to the uterine cavity. Close the incision in a single layer. Use of a surgical stapler can be used for the hysterotomy and can decrease the amount of blood loss.⁸

Superior attachments of the uterus

The superior attachments of the uterus include the round ligament, the utero-ovarian ligament, and the fallopian tubes. With meticulous dissection, develop an avascular space underneath these structures and, in turn, individually divide and suture ligate; this is typically achieved with minimal blood loss.

In addition, isolate the engorged veins of the broad ligament and divide them in a similar fashion.

In our experience. Use of a vessel-sealing device can facilitate division of all the former structures. Simply excise the fallopian tubes with the vessel-sealing device either at this time or after the uterus is removed.

Pelvic sidewall

Once the superior attachments of the uterus have been divided, the next step involves exposing the pelvic sidewall structures, that is, the ureter and the pelvic vessels. Expose the ureter from the pelvic brim to the level of the uterine artery. The hypogastric artery is exposed as well in this process and the pararectal space developed.

When the PAS has extended laterally, perform stepwise division of the lateral attachments of the placenta to the pelvic sidewall using a combination of electrocautery, hemoclips, and the vessel-sealing device. In laterally extended PAS cases, it often is necessary to divide the uterine artery either at its origin or at the level of the ureter to allow for the completion of the separation of the placenta from the pelvic sidewall.

In our experience. During this lateral dissection, significant bleeding may be encountered from the neovascular network that has developed in the pelvic sidewall. The bleeding may be diffuse and difficult to control with the methods described above. In this situation, we have found that placing hemostatic agents in this area and packing the sidewall with laparotomy pads can achieve hemostasis in most cases, thus allowing the surgery to proceed.

Continue to: Bladder dissection...

 

Bladder dissection

The next critical part of the surgery involves developing the vesicovaginal space to mobilize the bladder. Prior to initiating the bladder dissection, we routinely retrograde fill the bladder with 180 to 240 mL of saline mixed with methylene blue. This delineates the superior edge of the bladder and indicates the appropriate level to start the dissection. Then slowly develop the vesicouterine space using a combination of electrocautery and a vessel-sealing device until the bladder is mobilized to the level of the anterior vaginal wall. Many vascular connections are encountered at that level, and meticulous dissection and patience is required to systematically divide them all.

In our experience. This part of the surgery presents several challenges. The bladder wall may be invaded by the placenta, which will lead to an increased risk of bleeding and cystotomy during the dissection. In these cases, it might be preferable to create an intentional cystotomy to guide the dissection; at times, a limited excision of the involved bladder wall may be required. In other cases, even in the absence of bladder wall invasion, the bladder may be densely adherent to the uterine wall (usually due to a history of prior CDs), and bladder mobilization may be complicated by bleeding from the neovascular network that has developed between the placenta and bladder.

Uterine arteries and cervix

Once the placenta is separated from its lateral attachments and the bladder is mobilized, the next steps are similar to those in a standard abdominal hysterectomy. If the uterine arteries were not yet divided during the pelvic sidewall dissection, they are clamped, divided, and suture ligated at the level of the uterine isthmus. The decision whether to perform a supracervical or total hysterectomy depends on the level of cervical involvement by the placenta, surgeon preference, anatomic distortion, and bleeding from the cervix and anterior vaginal wall.

Responding to massive bleeding

Not uncommonly, and despite the best efforts to avoid it, massive bleeding may develop from the areas at risk as noted above. If the bleeding is significant and originates from multiple areas (including vaginal bleeding from placenta previa), we recommend proceeding with an expeditious hysterectomy to remove the specimen, and then reassess the pelvic field for hemostatic control and any organ damage that may have occurred.

The challenge of PAS

Surgical management of PAS is one the most challenging procedures in pelvic surgery. Successful outcomes require a multidisciplinary team approach and an experienced team dedicated to the management of this condition.⁹ By contrast, proceeding “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences in terms of maternal morbidity and mortality. ●

 

 

CASE Concerning finding on repeat CD

A 30-year-old woman with a history of 1 prior cesarean delivery (CD) presents to labor and delivery at 38 weeks of gestation with symptoms of mild cramping. Her prenatal care was uncomplicated. The covering team made a decision to proceed with a repeat CD. A Pfannenstiel incision is made to enter the abdomen, and inspection of the lower uterine segment is concerning for a placenta accreta spectrum (PAS) (FIGURE).

What would be your next steps?

 

Placenta accreta spectrum describes the range of disorders of placental implantation, including placenta accreta, increta, and percreta. PAS is a significant cause of severe maternal morbidity and mortality, primarily due to massive hemorrhage at the time of delivery. The incidence of PAS continues to rise along with the CD rate. The authors of a recent meta-analysis reported a pooled prevalence rate of 1 in 588 women.¹ Notably, in women with PAS, the rate of hysterectomy is 52.2%, and the transfusion-dependent hemorrhage rate is 46.9%.¹

Ideally, PAS should be diagnosed or at least suspected antenatally during prenatal ultrasonography, leading to delivery planning by a multidisciplinary team.² The presence of a multidisciplinary team—in addition to the primary obstetric and surgical teams—composed of experienced anesthesiologists, a blood bank able to respond to massive transfusion needs, critical care specialists, and interventional radiologists is associated with improved outcomes.^3-5

Occasionally, a patient is found to have an advanced PAS (increta or percreta) at the time of delivery. In these situations, it is paramount that the appropriate resources be assembled as expeditiously as possible to optimize maternal outcomes. Surgical management can be challenging even for experienced pelvic surgeons, and appropriate resuscitation cannot be provided by a single anesthesiologist working alone. A cavalier attitude of proceeding with the delivery “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences, including maternal death.

In this article, we review the important steps to take when faced with the unexpected situation of a PAS at the time of CD.

 

Continue to: Stop and collect your multidisciplinary team...

 

Stop and collect your multidisciplinary team

Once the diagnosis of an advanced PAS is suspected, the first step is to stop and request the presence of your institution’s multidisciplinary surgical team. This team typically includes a maternal-fetal specialist or, if not available, an experienced obstetrician, and an expert pelvic surgeon, which varies by institution (gynecologic oncologist, trauma surgeon, urologist, urogynecologist, vascular surgeon). An interventional radiology team is an additional useful resource that can assist with the control of pelvic hemorrhage using embolization techniques.

In our opinion, it is not appropriate to have a surgical backup team available only as needed at a certain distance from the hospital or even in the building. Because of the acuity and magnitude of bleeding that can occur in a short time, the most appropriate approach is to have your surgical team scrubbed and ready to assist or take over the procedure immediately if indicated.

Additional support staff also may be required. A single circulating nurse may not be sufficient, and available nursing staff may need to be called. The surgical technician scrubbed on the case may be familiar only with uncomplicated CDs and can be overwhelmed during a PAS case. Having a more experienced surgical technologist can optimize the availability of the appropriate instruments for the surgical team.

If a multidisciplinary surgical team with PAS management expertise is not available at your institution and the patient is stable, it is appropriate to consider transferring her to the nearest center that can meet the high-risk needs of this situation.⁶

Prepare for resuscitation

While you are calling your multidisciplinary team members, implement plans for resuscitation by notifying the anesthesiologist about the PAS findings. This will allow the gathering of needed resources that may include calling on additional anesthesiologists with experience in high-risk obstetrics, trauma, or critical care.

Placing large-bore intravenous lines or a central line to allow rapid transfusion is essential. Strongly consider inserting an arterial line for hemodynamic monitoring and intraoperative blood draws to monitor blood loss, blood gases, electrolytes, and coagulation parameters, which can guide resuscitative efforts and replacement therapies.

Simultaneously, inform the blood bank to prepare blood and blood products for possible activation of a massive transfusion protocol. It is imperative to have the products available in the operating room (OR) prior to proceeding with the surgery. Our current practice is to have 10 units of packed red blood cells and fresh frozen plasma available in the OR for all our prenatally diagnosed electively planned PAS cases.

Optimize exposure of the surgical field

Appropriate exposure of the surgical field is essential and should include exposure of the uterine fundus and the pelvic sidewalls. The uterine incision should avoid the placenta; typically it is placed at the level of the uterine fundus. Exposure of the pelvic sidewalls is needed to open the retroperitoneum and identify the ureter and the iliac vessels.

Vertical extension of the fascial incision probably will be needed to achieve appropriate exposure. Although at times this can be done without a concomitant vertical skin incision, often an inverted T incision is required. Be mindful that PAS is a life-threatening condition and that aesthetics are not a priority. After extending the fascial incision, adequate exposure can be achieved with any of the commonly used retractors or wound protectors (depending on institutional availability and surgeon preference) or by the surgical assistants using body wall retractors.

We routinely place the patient in lithotomy position. This allows us to monitor for vaginal bleeding (often a site of unrecognized massive hemorrhage) during the surgery, facilitate retrograde bladder filling, and provide a vaginal access to the pelvis. In addition, the lithotomy position allows for cystoscopy and placement of ureteral stents, which can be performed before starting the surgery to help prevent urinary tract injuries or at the end of the procedure in case one is suspected.⁷

 

Continue to: Performing the hysterectomy...

 

 

 

Performing the hysterectomy

A complete review of all surgical techniques for managing PAS is beyond the scope of this article. However, we briefly cover important procedural steps and offer suggestions on how to minimize the risk of bleeding.

In our experience. The areas with the highest risk of massive bleeding that can be difficult to control include the pelvic sidewall when there is lateral extension of the PAS, the vesicouterine space, and placenta previa vaginally. Be mindful of these areas at risk and have a plan in place in case of bleeding.

Uterine incision

Avoid the placenta when making the uterine incision, which is typically done in the fundal part of the uterus. Cut and tie the cord and return it to the uterine cavity. Close the incision in a single layer. Use of a surgical stapler can be used for the hysterotomy and can decrease the amount of blood loss.⁸

Superior attachments of the uterus

The superior attachments of the uterus include the round ligament, the utero-ovarian ligament, and the fallopian tubes. With meticulous dissection, develop an avascular space underneath these structures and, in turn, individually divide and suture ligate; this is typically achieved with minimal blood loss.

In addition, isolate the engorged veins of the broad ligament and divide them in a similar fashion.

In our experience. Use of a vessel-sealing device can facilitate division of all the former structures. Simply excise the fallopian tubes with the vessel-sealing device either at this time or after the uterus is removed.

Pelvic sidewall

Once the superior attachments of the uterus have been divided, the next step involves exposing the pelvic sidewall structures, that is, the ureter and the pelvic vessels. Expose the ureter from the pelvic brim to the level of the uterine artery. The hypogastric artery is exposed as well in this process and the pararectal space developed.

When the PAS has extended laterally, perform stepwise division of the lateral attachments of the placenta to the pelvic sidewall using a combination of electrocautery, hemoclips, and the vessel-sealing device. In laterally extended PAS cases, it often is necessary to divide the uterine artery either at its origin or at the level of the ureter to allow for the completion of the separation of the placenta from the pelvic sidewall.

In our experience. During this lateral dissection, significant bleeding may be encountered from the neovascular network that has developed in the pelvic sidewall. The bleeding may be diffuse and difficult to control with the methods described above. In this situation, we have found that placing hemostatic agents in this area and packing the sidewall with laparotomy pads can achieve hemostasis in most cases, thus allowing the surgery to proceed.

Continue to: Bladder dissection...

 

Bladder dissection

The next critical part of the surgery involves developing the vesicovaginal space to mobilize the bladder. Prior to initiating the bladder dissection, we routinely retrograde fill the bladder with 180 to 240 mL of saline mixed with methylene blue. This delineates the superior edge of the bladder and indicates the appropriate level to start the dissection. Then slowly develop the vesicouterine space using a combination of electrocautery and a vessel-sealing device until the bladder is mobilized to the level of the anterior vaginal wall. Many vascular connections are encountered at that level, and meticulous dissection and patience is required to systematically divide them all.

In our experience. This part of the surgery presents several challenges. The bladder wall may be invaded by the placenta, which will lead to an increased risk of bleeding and cystotomy during the dissection. In these cases, it might be preferable to create an intentional cystotomy to guide the dissection; at times, a limited excision of the involved bladder wall may be required. In other cases, even in the absence of bladder wall invasion, the bladder may be densely adherent to the uterine wall (usually due to a history of prior CDs), and bladder mobilization may be complicated by bleeding from the neovascular network that has developed between the placenta and bladder.

Uterine arteries and cervix

Once the placenta is separated from its lateral attachments and the bladder is mobilized, the next steps are similar to those in a standard abdominal hysterectomy. If the uterine arteries were not yet divided during the pelvic sidewall dissection, they are clamped, divided, and suture ligated at the level of the uterine isthmus. The decision whether to perform a supracervical or total hysterectomy depends on the level of cervical involvement by the placenta, surgeon preference, anatomic distortion, and bleeding from the cervix and anterior vaginal wall.

Responding to massive bleeding

Not uncommonly, and despite the best efforts to avoid it, massive bleeding may develop from the areas at risk as noted above. If the bleeding is significant and originates from multiple areas (including vaginal bleeding from placenta previa), we recommend proceeding with an expeditious hysterectomy to remove the specimen, and then reassess the pelvic field for hemostatic control and any organ damage that may have occurred.

The challenge of PAS

Surgical management of PAS is one the most challenging procedures in pelvic surgery. Successful outcomes require a multidisciplinary team approach and an experienced team dedicated to the management of this condition.⁹ By contrast, proceeding “as usual” in the face of an unexpected PAS situation can lead to disastrous consequences in terms of maternal morbidity and mortality. ●

Pelvic organ prolapse (POP) is a common occurrence over the course of a woman’s lifetime, especially in parous women (up to 50% of women who have given birth).¹ The anterior vaginal wall is the most common site of POP and has the highest recurrence rate of up to 70%.² The risk of developing POP increases with age, obesity, White race, family history, and prior pelvic surgery, such as hysterectomy. It affects more than 3 million women in the United States alone, often negatively impacting sexual function and overall quality of life.^3,4

Because women are living longer than ever before and are more active in their senior years, a long-lasting, durable surgical repair is desirable, if not necessary. To be cost-effective and to avoid general anesthesia, the surgical approach ideally should be vaginal.

Biologic and synthetic grafts to augment transvaginal repair traditionally are used to improve on the well-recognized high failure rate of native-tissue repair that is often seen at both short-term and medium-term follow-up.⁵ The failure rate is commonly referenced as 30% to 40% at 2-year follow-up and 61% to 70% at 5-year follow-up, well-established by the results of the OPTIMAL randomized clinical trial.⁶ The more recent Descent trial likewise demonstrates a higher failure rate of native-tissue repair versus transvaginal mesh repair at a shorter term of 30 to 42 months.⁷ Furthermore, the use of permanent versus absorbable suture in suspension of the vaginal apex is associated with lower short-term failure rates.⁸

Despite this Level I evidence that demonstrates a clear advantage for obtaining a longer or more durable repair with permanent materials, native-tissue repairs with absorbable suture are still performed routinely. Since the US Food and Drug Administration (FDA) ordered that the use of transvaginal surgical mesh augmentation for pelvic reconstructive surgery be discontinued, it is more important than ever to explore evolving alternative native-tissue augmentation repair techniques that hopefully can preserve the advantages and merits of vaginal surgery and achieve longer durability.⁹

Biologic graft augmentation use in transvaginal reconstruction

All biologic grafts, including allografts derived from human tissue and xenografts derived from animal tissue, are acellular constructs composed of extracellular matrix (ECM) that acts as scaffolding for the host tissue. The ECM is predominantly composed of collagen (types I and III) and noncollagenous fibronectin, laminin, and glycosaminoglycans in various amounts depending on the source tissue. The 3D presentation of ECM’s complex molecules allows for rapid repopulation of host cells and revascularization with eventual regeneration.

Once a biologic graft is placed surgically, the body’s response to the scaffold ECM mimics the normal wound-healing process, beginning with fibrin-rich matrix hemostasis and the subsequent innate immune response of neutrophil and M1 macrophage infiltration. M1 macrophages are proinflammatory and clear cellular debris and begin the process of graft scaffold degradation. The host tissue then begins the process of remodeling through pro-remodeling M2 macrophages and stem cell recruitment, proliferation, and differentiation.¹⁰ As the biologic graft provides initial structure and strength for pelvic repairs, the ideal ECM scaffold would not degrade before the host is able to fully undergo regeneration and maintain its structure and strength.

Biologic grafts differ in source (allograft or xenograft), type (pericardium, dermis, or bladder), developmental stage (fetal or adult), decellularization processing, and sterilization techniques. These 5 aspects determine the distinct 3D ECM scaffold structure, strength, and longevity. If the ECM scaffold is damaged or retains noncollagenous proteins during the preparation process, an inflammatory response is triggered in which the graft is degraded, resorbed, and replaced with scar tissue. Furthermore, certain processing techniques aimed at extending the ECM’s durability—that is, cross-linking collagen—results in the foreign body response in which there is no vascular infiltration or cellular penetration of the graft and a collagen capsule is created around the empty matrix.¹¹ To avoid resorption or encapsulation of the graft, the ECM scaffolds of biologic grafts must be optimized to induce regeneration.

Continue to: Choosing surgical POP repair...

 

Choosing surgical POP repair

The decision to undergo surgical treatment for prolapse is a shared decision-making process between the patient and surgeon and always should be individualized. The type of procedure and the surgical approach will depend on the patient’s goals, the degree of prolapse, clinical history, risk tolerance, the surgeon’s skill set, and whether or not there is an indication or relative contraindication for uterine removal at the time of prolapse repair.

While the FDA’s order does not apply to transabdominally placed surgical mesh, such as sacrocolpopexy, not all patients are ideal candidates for an abdominal sacrocolpopexy. Most notable are women with a history of multiple prior abdominal surgeries with higher rates of intraperitoneal adhesions. Ideally, to be cost-effective and to avoid general anesthesia, the surgical approach should be vaginal whenever possible.

Biologic versus native-tissue grafts

Currently, only low-quality evidence exists that compares the outcomes of biologic grafts with traditional native-tissue repairs in POP. Studies have been limited by poor reporting of methods, inconsistency in technique and materials used, and imprecise definitions. One Cochrane Review on the surgical management of POP concluded that biologic graft augmentation was associated with a lower failure rate (18%) within 1 to 2 years when compared with a traditional anterior colporrhaphy (28%).¹²

Based on consideration of all Cochrane Database Reviews and recent large systematic reviews, there clearly is a paucity of information on which to draw well-defined conclusions regarding the advantage of biomaterials in prolapse surgery.^12-14 This is due in part to the variation in graft material used and the surgical technique employed.

Similarly, evidence is lacking regarding the superiority of one type of biologic graft over another. Furthermore, some of the grafts previously studied are no longer on the market.¹⁵ With the FDA’s removal of all transvaginal mesh, including xenografts, only allografts are available for pelvic floor reconstruction. Currently, only 3 commercial manufacturers market allografts for pelvic floor reconstruction. Each allograft is available in various sizes and all can be trimmed at the time of the surgical procedure to customize both the size and shape to fit the individual patient.

A novel technique using Axis Dermis and polypropylene suture

One of the commercially available allografts, Axis Dermis (Coloplast), is non–cross-linked and is derived from human cadaveric dermal tissue from the back and dorsum of the upper leg. It is sterilized by a proprietary Tutoplast️ sterilization process that uses gamma irradiation to inactivate and prevent the transmission of pathogens. This unique technique involving solvent dehydration means the graft is never freeze dried; thus, the natural tissue matrix is preserved.

Additionally, the allograft is antigen-free, which decreases the risk of tissue reaction (scarring/fibrosis) and aids in the process of host tissue remodeling; invasion by growth factors, blood cells, collagen, elastin, and neovascularization. This natural tissue remodeling facilitates the anticipated “reabsorption” of the graft by the host tissue, leaving the patient with a tissue scaffold, that is, a stronger layer of “fascia” beneath the muscularis.¹⁶ As a result of this “biocompatible” graft, the host tissue remodeling has been shown in the rat model to involve early cellular infiltration and angiogenesis (in the first week after implantation), that leads to an organized cellular architecture with greater tensile strength by week 4, and ultimately inability to distinguish host collagen from the implant by 8 to 12 weeks.^17,18

Continue to: Steps in performing the technique...

 

Steps in performing the technique

To ensure that the graft is placed adjacent to the vaginal serosa, a full-thickness dissection is carried out to enter the true vesicovaginal space, which lies below all 4 histologic layers of the vagina (nonkeratinized stratified squamous epithelium, lamina propria, muscularis, and serosa). For the anterior dissection, a Tuohy epidural needle is used to achieve an accurate and consistent depth when injecting fluid (hydrodissection) to enter this true pelvic space (FIGURE 1). Correct entry into the vesicovaginal space can be confirmed visually by the presence of adipose tissue.

Many pelvic surgeons use the sacrospinous ligament (SSL) as a strong and reliable point of attachment for vaginal prolapse repair. It can be approached either anteriorly or posteriorly with careful dissection. Permanent suture (0-Prolene) is used to “bridge” the attachment between the SSL, the Axis Dermis graft, and the cervix (or vaginal apex). The suture is placed in the middle third and lower half of the ligament to avoid injury to nearby neurovascular structures.

While the surgeon may use any suture-capturing device, we prefer the Anchosure System (Neomedic). This device delivers a small anchor securely into the ligament through a single point of entry, minimizing the risk of postoperative pain for the patient. A 6 cm x 8 cm size Axis Dermis graft is then trimmed to meet the specifications of the patient’s anatomy.

Most commonly, we measure, mark, and trim the body of the graft to 5.5 cm in length with a width of 3 cm. The bilateral arms are approximately 1 cm in width and comprise the remaining length of the 8 cm graft (FIGURE 2). As shown in Figure 2, pre-made holes are marked and punched out using a large hollow needle. These serve as the points of attachment for the permanent suture to be “weaved” into the graft arms and delayed absorbable “tacking suture” to be attached from the pubocervical fascia at the bladder neck to the distal end of the graft. This facilitates fixation of the graft in the midline of the anterior vaginal wall, overlying any central distention-type defect.

Finally, following attachment of the SSL permanent suture to the distal graft arm, this suture is then attached to the proximal U-shaped end of the graft body (in the midline), followed by a deep and secure bite through the cervix (or vaginal vault apex) and back through the proximal graft. These SSL suspension sutures are then tied such that the distal arms of the graft advance down to the ligament. Care is taken not to tie down to the SSL itself, rather until the cervix (or apex) is reduced to its normal anatomical location.

After the graft is secured in place, the full-thickness vaginal wall is closed with delayed absorbable suture. Sterile 1-inch ribbon packing is placed in the vagina immediately to close any dead space between the vagina and the graft to decrease the risk of seroma or hematoma formation.

This newly developed technique, like many surgeries for POP, requires extensive knowledge of pelvic anatomy and skill in vaginal surgery, and we recommend referral to a subspecialist in Female Pelvic Medicine and Reconstructive Surgery.

Pelvic organ prolapse (POP) is a common occurrence over the course of a woman’s lifetime, especially in parous women (up to 50% of women who have given birth).¹ The anterior vaginal wall is the most common site of POP and has the highest recurrence rate of up to 70%.² The risk of developing POP increases with age, obesity, White race, family history, and prior pelvic surgery, such as hysterectomy. It affects more than 3 million women in the United States alone, often negatively impacting sexual function and overall quality of life.^3,4

Because women are living longer than ever before and are more active in their senior years, a long-lasting, durable surgical repair is desirable, if not necessary. To be cost-effective and to avoid general anesthesia, the surgical approach ideally should be vaginal.

Biologic and synthetic grafts to augment transvaginal repair traditionally are used to improve on the well-recognized high failure rate of native-tissue repair that is often seen at both short-term and medium-term follow-up.⁵ The failure rate is commonly referenced as 30% to 40% at 2-year follow-up and 61% to 70% at 5-year follow-up, well-established by the results of the OPTIMAL randomized clinical trial.⁶ The more recent Descent trial likewise demonstrates a higher failure rate of native-tissue repair versus transvaginal mesh repair at a shorter term of 30 to 42 months.⁷ Furthermore, the use of permanent versus absorbable suture in suspension of the vaginal apex is associated with lower short-term failure rates.⁸

Despite this Level I evidence that demonstrates a clear advantage for obtaining a longer or more durable repair with permanent materials, native-tissue repairs with absorbable suture are still performed routinely. Since the US Food and Drug Administration (FDA) ordered that the use of transvaginal surgical mesh augmentation for pelvic reconstructive surgery be discontinued, it is more important than ever to explore evolving alternative native-tissue augmentation repair techniques that hopefully can preserve the advantages and merits of vaginal surgery and achieve longer durability.⁹

Biologic graft augmentation use in transvaginal reconstruction

All biologic grafts, including allografts derived from human tissue and xenografts derived from animal tissue, are acellular constructs composed of extracellular matrix (ECM) that acts as scaffolding for the host tissue. The ECM is predominantly composed of collagen (types I and III) and noncollagenous fibronectin, laminin, and glycosaminoglycans in various amounts depending on the source tissue. The 3D presentation of ECM’s complex molecules allows for rapid repopulation of host cells and revascularization with eventual regeneration.

Once a biologic graft is placed surgically, the body’s response to the scaffold ECM mimics the normal wound-healing process, beginning with fibrin-rich matrix hemostasis and the subsequent innate immune response of neutrophil and M1 macrophage infiltration. M1 macrophages are proinflammatory and clear cellular debris and begin the process of graft scaffold degradation. The host tissue then begins the process of remodeling through pro-remodeling M2 macrophages and stem cell recruitment, proliferation, and differentiation.¹⁰ As the biologic graft provides initial structure and strength for pelvic repairs, the ideal ECM scaffold would not degrade before the host is able to fully undergo regeneration and maintain its structure and strength.

Biologic grafts differ in source (allograft or xenograft), type (pericardium, dermis, or bladder), developmental stage (fetal or adult), decellularization processing, and sterilization techniques. These 5 aspects determine the distinct 3D ECM scaffold structure, strength, and longevity. If the ECM scaffold is damaged or retains noncollagenous proteins during the preparation process, an inflammatory response is triggered in which the graft is degraded, resorbed, and replaced with scar tissue. Furthermore, certain processing techniques aimed at extending the ECM’s durability—that is, cross-linking collagen—results in the foreign body response in which there is no vascular infiltration or cellular penetration of the graft and a collagen capsule is created around the empty matrix.¹¹ To avoid resorption or encapsulation of the graft, the ECM scaffolds of biologic grafts must be optimized to induce regeneration.

Continue to: Choosing surgical POP repair...

 

Choosing surgical POP repair

The decision to undergo surgical treatment for prolapse is a shared decision-making process between the patient and surgeon and always should be individualized. The type of procedure and the surgical approach will depend on the patient’s goals, the degree of prolapse, clinical history, risk tolerance, the surgeon’s skill set, and whether or not there is an indication or relative contraindication for uterine removal at the time of prolapse repair.

While the FDA’s order does not apply to transabdominally placed surgical mesh, such as sacrocolpopexy, not all patients are ideal candidates for an abdominal sacrocolpopexy. Most notable are women with a history of multiple prior abdominal surgeries with higher rates of intraperitoneal adhesions. Ideally, to be cost-effective and to avoid general anesthesia, the surgical approach should be vaginal whenever possible.

Biologic versus native-tissue grafts

Currently, only low-quality evidence exists that compares the outcomes of biologic grafts with traditional native-tissue repairs in POP. Studies have been limited by poor reporting of methods, inconsistency in technique and materials used, and imprecise definitions. One Cochrane Review on the surgical management of POP concluded that biologic graft augmentation was associated with a lower failure rate (18%) within 1 to 2 years when compared with a traditional anterior colporrhaphy (28%).¹²

Based on consideration of all Cochrane Database Reviews and recent large systematic reviews, there clearly is a paucity of information on which to draw well-defined conclusions regarding the advantage of biomaterials in prolapse surgery.^12-14 This is due in part to the variation in graft material used and the surgical technique employed.

Similarly, evidence is lacking regarding the superiority of one type of biologic graft over another. Furthermore, some of the grafts previously studied are no longer on the market.¹⁵ With the FDA’s removal of all transvaginal mesh, including xenografts, only allografts are available for pelvic floor reconstruction. Currently, only 3 commercial manufacturers market allografts for pelvic floor reconstruction. Each allograft is available in various sizes and all can be trimmed at the time of the surgical procedure to customize both the size and shape to fit the individual patient.

A novel technique using Axis Dermis and polypropylene suture

One of the commercially available allografts, Axis Dermis (Coloplast), is non–cross-linked and is derived from human cadaveric dermal tissue from the back and dorsum of the upper leg. It is sterilized by a proprietary Tutoplast️ sterilization process that uses gamma irradiation to inactivate and prevent the transmission of pathogens. This unique technique involving solvent dehydration means the graft is never freeze dried; thus, the natural tissue matrix is preserved.

Additionally, the allograft is antigen-free, which decreases the risk of tissue reaction (scarring/fibrosis) and aids in the process of host tissue remodeling; invasion by growth factors, blood cells, collagen, elastin, and neovascularization. This natural tissue remodeling facilitates the anticipated “reabsorption” of the graft by the host tissue, leaving the patient with a tissue scaffold, that is, a stronger layer of “fascia” beneath the muscularis.¹⁶ As a result of this “biocompatible” graft, the host tissue remodeling has been shown in the rat model to involve early cellular infiltration and angiogenesis (in the first week after implantation), that leads to an organized cellular architecture with greater tensile strength by week 4, and ultimately inability to distinguish host collagen from the implant by 8 to 12 weeks.^17,18

Continue to: Steps in performing the technique...

 

Steps in performing the technique

To ensure that the graft is placed adjacent to the vaginal serosa, a full-thickness dissection is carried out to enter the true vesicovaginal space, which lies below all 4 histologic layers of the vagina (nonkeratinized stratified squamous epithelium, lamina propria, muscularis, and serosa). For the anterior dissection, a Tuohy epidural needle is used to achieve an accurate and consistent depth when injecting fluid (hydrodissection) to enter this true pelvic space (FIGURE 1). Correct entry into the vesicovaginal space can be confirmed visually by the presence of adipose tissue.

Many pelvic surgeons use the sacrospinous ligament (SSL) as a strong and reliable point of attachment for vaginal prolapse repair. It can be approached either anteriorly or posteriorly with careful dissection. Permanent suture (0-Prolene) is used to “bridge” the attachment between the SSL, the Axis Dermis graft, and the cervix (or vaginal apex). The suture is placed in the middle third and lower half of the ligament to avoid injury to nearby neurovascular structures.

While the surgeon may use any suture-capturing device, we prefer the Anchosure System (Neomedic). This device delivers a small anchor securely into the ligament through a single point of entry, minimizing the risk of postoperative pain for the patient. A 6 cm x 8 cm size Axis Dermis graft is then trimmed to meet the specifications of the patient’s anatomy.

Most commonly, we measure, mark, and trim the body of the graft to 5.5 cm in length with a width of 3 cm. The bilateral arms are approximately 1 cm in width and comprise the remaining length of the 8 cm graft (FIGURE 2). As shown in Figure 2, pre-made holes are marked and punched out using a large hollow needle. These serve as the points of attachment for the permanent suture to be “weaved” into the graft arms and delayed absorbable “tacking suture” to be attached from the pubocervical fascia at the bladder neck to the distal end of the graft. This facilitates fixation of the graft in the midline of the anterior vaginal wall, overlying any central distention-type defect.

Finally, following attachment of the SSL permanent suture to the distal graft arm, this suture is then attached to the proximal U-shaped end of the graft body (in the midline), followed by a deep and secure bite through the cervix (or vaginal vault apex) and back through the proximal graft. These SSL suspension sutures are then tied such that the distal arms of the graft advance down to the ligament. Care is taken not to tie down to the SSL itself, rather until the cervix (or apex) is reduced to its normal anatomical location.

After the graft is secured in place, the full-thickness vaginal wall is closed with delayed absorbable suture. Sterile 1-inch ribbon packing is placed in the vagina immediately to close any dead space between the vagina and the graft to decrease the risk of seroma or hematoma formation.

This newly developed technique, like many surgeries for POP, requires extensive knowledge of pelvic anatomy and skill in vaginal surgery, and we recommend referral to a subspecialist in Female Pelvic Medicine and Reconstructive Surgery.

Pelvic organ prolapse (POP) is a common occurrence over the course of a woman’s lifetime, especially in parous women (up to 50% of women who have given birth).¹ The anterior vaginal wall is the most common site of POP and has the highest recurrence rate of up to 70%.² The risk of developing POP increases with age, obesity, White race, family history, and prior pelvic surgery, such as hysterectomy. It affects more than 3 million women in the United States alone, often negatively impacting sexual function and overall quality of life.^3,4

Because women are living longer than ever before and are more active in their senior years, a long-lasting, durable surgical repair is desirable, if not necessary. To be cost-effective and to avoid general anesthesia, the surgical approach ideally should be vaginal.

Biologic and synthetic grafts to augment transvaginal repair traditionally are used to improve on the well-recognized high failure rate of native-tissue repair that is often seen at both short-term and medium-term follow-up.⁵ The failure rate is commonly referenced as 30% to 40% at 2-year follow-up and 61% to 70% at 5-year follow-up, well-established by the results of the OPTIMAL randomized clinical trial.⁶ The more recent Descent trial likewise demonstrates a higher failure rate of native-tissue repair versus transvaginal mesh repair at a shorter term of 30 to 42 months.⁷ Furthermore, the use of permanent versus absorbable suture in suspension of the vaginal apex is associated with lower short-term failure rates.⁸

Despite this Level I evidence that demonstrates a clear advantage for obtaining a longer or more durable repair with permanent materials, native-tissue repairs with absorbable suture are still performed routinely. Since the US Food and Drug Administration (FDA) ordered that the use of transvaginal surgical mesh augmentation for pelvic reconstructive surgery be discontinued, it is more important than ever to explore evolving alternative native-tissue augmentation repair techniques that hopefully can preserve the advantages and merits of vaginal surgery and achieve longer durability.⁹

Biologic graft augmentation use in transvaginal reconstruction

All biologic grafts, including allografts derived from human tissue and xenografts derived from animal tissue, are acellular constructs composed of extracellular matrix (ECM) that acts as scaffolding for the host tissue. The ECM is predominantly composed of collagen (types I and III) and noncollagenous fibronectin, laminin, and glycosaminoglycans in various amounts depending on the source tissue. The 3D presentation of ECM’s complex molecules allows for rapid repopulation of host cells and revascularization with eventual regeneration.

Once a biologic graft is placed surgically, the body’s response to the scaffold ECM mimics the normal wound-healing process, beginning with fibrin-rich matrix hemostasis and the subsequent innate immune response of neutrophil and M1 macrophage infiltration. M1 macrophages are proinflammatory and clear cellular debris and begin the process of graft scaffold degradation. The host tissue then begins the process of remodeling through pro-remodeling M2 macrophages and stem cell recruitment, proliferation, and differentiation.¹⁰ As the biologic graft provides initial structure and strength for pelvic repairs, the ideal ECM scaffold would not degrade before the host is able to fully undergo regeneration and maintain its structure and strength.

Biologic grafts differ in source (allograft or xenograft), type (pericardium, dermis, or bladder), developmental stage (fetal or adult), decellularization processing, and sterilization techniques. These 5 aspects determine the distinct 3D ECM scaffold structure, strength, and longevity. If the ECM scaffold is damaged or retains noncollagenous proteins during the preparation process, an inflammatory response is triggered in which the graft is degraded, resorbed, and replaced with scar tissue. Furthermore, certain processing techniques aimed at extending the ECM’s durability—that is, cross-linking collagen—results in the foreign body response in which there is no vascular infiltration or cellular penetration of the graft and a collagen capsule is created around the empty matrix.¹¹ To avoid resorption or encapsulation of the graft, the ECM scaffolds of biologic grafts must be optimized to induce regeneration.

Continue to: Choosing surgical POP repair...

 

Choosing surgical POP repair

The decision to undergo surgical treatment for prolapse is a shared decision-making process between the patient and surgeon and always should be individualized. The type of procedure and the surgical approach will depend on the patient’s goals, the degree of prolapse, clinical history, risk tolerance, the surgeon’s skill set, and whether or not there is an indication or relative contraindication for uterine removal at the time of prolapse repair.

While the FDA’s order does not apply to transabdominally placed surgical mesh, such as sacrocolpopexy, not all patients are ideal candidates for an abdominal sacrocolpopexy. Most notable are women with a history of multiple prior abdominal surgeries with higher rates of intraperitoneal adhesions. Ideally, to be cost-effective and to avoid general anesthesia, the surgical approach should be vaginal whenever possible.

Biologic versus native-tissue grafts

Currently, only low-quality evidence exists that compares the outcomes of biologic grafts with traditional native-tissue repairs in POP. Studies have been limited by poor reporting of methods, inconsistency in technique and materials used, and imprecise definitions. One Cochrane Review on the surgical management of POP concluded that biologic graft augmentation was associated with a lower failure rate (18%) within 1 to 2 years when compared with a traditional anterior colporrhaphy (28%).¹²

Based on consideration of all Cochrane Database Reviews and recent large systematic reviews, there clearly is a paucity of information on which to draw well-defined conclusions regarding the advantage of biomaterials in prolapse surgery.^12-14 This is due in part to the variation in graft material used and the surgical technique employed.

Similarly, evidence is lacking regarding the superiority of one type of biologic graft over another. Furthermore, some of the grafts previously studied are no longer on the market.¹⁵ With the FDA’s removal of all transvaginal mesh, including xenografts, only allografts are available for pelvic floor reconstruction. Currently, only 3 commercial manufacturers market allografts for pelvic floor reconstruction. Each allograft is available in various sizes and all can be trimmed at the time of the surgical procedure to customize both the size and shape to fit the individual patient.

A novel technique using Axis Dermis and polypropylene suture

One of the commercially available allografts, Axis Dermis (Coloplast), is non–cross-linked and is derived from human cadaveric dermal tissue from the back and dorsum of the upper leg. It is sterilized by a proprietary Tutoplast️ sterilization process that uses gamma irradiation to inactivate and prevent the transmission of pathogens. This unique technique involving solvent dehydration means the graft is never freeze dried; thus, the natural tissue matrix is preserved.

Additionally, the allograft is antigen-free, which decreases the risk of tissue reaction (scarring/fibrosis) and aids in the process of host tissue remodeling; invasion by growth factors, blood cells, collagen, elastin, and neovascularization. This natural tissue remodeling facilitates the anticipated “reabsorption” of the graft by the host tissue, leaving the patient with a tissue scaffold, that is, a stronger layer of “fascia” beneath the muscularis.¹⁶ As a result of this “biocompatible” graft, the host tissue remodeling has been shown in the rat model to involve early cellular infiltration and angiogenesis (in the first week after implantation), that leads to an organized cellular architecture with greater tensile strength by week 4, and ultimately inability to distinguish host collagen from the implant by 8 to 12 weeks.^17,18

Continue to: Steps in performing the technique...

 

Steps in performing the technique

To ensure that the graft is placed adjacent to the vaginal serosa, a full-thickness dissection is carried out to enter the true vesicovaginal space, which lies below all 4 histologic layers of the vagina (nonkeratinized stratified squamous epithelium, lamina propria, muscularis, and serosa). For the anterior dissection, a Tuohy epidural needle is used to achieve an accurate and consistent depth when injecting fluid (hydrodissection) to enter this true pelvic space (FIGURE 1). Correct entry into the vesicovaginal space can be confirmed visually by the presence of adipose tissue.

Many pelvic surgeons use the sacrospinous ligament (SSL) as a strong and reliable point of attachment for vaginal prolapse repair. It can be approached either anteriorly or posteriorly with careful dissection. Permanent suture (0-Prolene) is used to “bridge” the attachment between the SSL, the Axis Dermis graft, and the cervix (or vaginal apex). The suture is placed in the middle third and lower half of the ligament to avoid injury to nearby neurovascular structures.

While the surgeon may use any suture-capturing device, we prefer the Anchosure System (Neomedic). This device delivers a small anchor securely into the ligament through a single point of entry, minimizing the risk of postoperative pain for the patient. A 6 cm x 8 cm size Axis Dermis graft is then trimmed to meet the specifications of the patient’s anatomy.

Most commonly, we measure, mark, and trim the body of the graft to 5.5 cm in length with a width of 3 cm. The bilateral arms are approximately 1 cm in width and comprise the remaining length of the 8 cm graft (FIGURE 2). As shown in Figure 2, pre-made holes are marked and punched out using a large hollow needle. These serve as the points of attachment for the permanent suture to be “weaved” into the graft arms and delayed absorbable “tacking suture” to be attached from the pubocervical fascia at the bladder neck to the distal end of the graft. This facilitates fixation of the graft in the midline of the anterior vaginal wall, overlying any central distention-type defect.

Finally, following attachment of the SSL permanent suture to the distal graft arm, this suture is then attached to the proximal U-shaped end of the graft body (in the midline), followed by a deep and secure bite through the cervix (or vaginal vault apex) and back through the proximal graft. These SSL suspension sutures are then tied such that the distal arms of the graft advance down to the ligament. Care is taken not to tie down to the SSL itself, rather until the cervix (or apex) is reduced to its normal anatomical location.

After the graft is secured in place, the full-thickness vaginal wall is closed with delayed absorbable suture. Sterile 1-inch ribbon packing is placed in the vagina immediately to close any dead space between the vagina and the graft to decrease the risk of seroma or hematoma formation.

This newly developed technique, like many surgeries for POP, requires extensive knowledge of pelvic anatomy and skill in vaginal surgery, and we recommend referral to a subspecialist in Female Pelvic Medicine and Reconstructive Surgery.