Biologic mesh in pelvic organ prolapse

Adverse events associated with the use of synthetic mesh in pelvic organ prolapse (POP) reparative surgery – and the Food and Drug Administration’s safety communication in 2011 warning physicians and patients about transvaginal placement of mesh for the repair of POP and stress urinary incontinence – have had a significant impact on gynecologic surgery.

Many physicians have become reluctant to use synthetic mesh products because of the risks of mesh erosion, exposure, pain and dyspareunia, and litigation. Patients also are concerned or even alarmed by reported risks. Moreover, some manufacturers have become increasingly concerned with the production of mesh products for POP repair, lessening the availability of synthetic mesh, and possibly some biologic mesh as well, for POP reparative surgery. Overall, the future of mesh augmentation in POP repair is uncertain.

Vaginal mesh procedures had surged in the decade prior to 2011 despite the lack of good randomized studies to determine whether mesh augmentation was truly efficacious. And unfortunately, the FDA has grouped synthetic and biologic material together in its reviews and notices of mesh products for POP repair. Not classifying and investigating them separately can mislead patients and hinder the development of randomized controlled trials needed to determine if augmentation with biologic material is truly superior to traditional POP repair using native tissue.

Comparing biologic mesh products to synthetic materials for pelvic organ prolapse repairs is like comparing apples to oranges: Synthetic mesh is permanent, while most biologics break down and remain in the body no longer than 6 months. From the standpoint of complications, this gives biologic materials an advantage. In my practice, biologic grafts have not eroded or caused pain, dyspareunia, or postoperative infections in any of my patients who have had surgical repair for POP.

There remains a real need for augmentation of weakened collagen tissue in the repair of POP. The native tissue in these patients is faulty tissue. Without reinforcement of defective tissue, we cannot expect excellent repairs. Data from nonrandomized studies have borne this out. When I talk with my patients about the options for surgical correction of POP, I tell them that success rates without the use of any augmentation are low, and that only about 60% of patients achieve a satisfactory result with traditional repairs.

Increasingly, I and other gynecologic surgeons are having success with biologic materials in our POP repairs. Efficacy needs to be measured in well-controlled randomized clinical trials, but at this point it appears anecdotally and from nonrandomized case reports that we can achieve good anatomic outcomes – upwards of 80% success rates – with biologic grafts, without the complications of synthetic mesh.

A recent survey of members of the American Urogynecologic Society shows that the use of synthetic mesh in transvaginal POP surgery decreased significantly after the 2011 FDA safety update, while there was no significant change in the use of biologic graft for POP (Female Pelvic Med. Reconstr. Surg 2013;19:191-8). It may be that the tide will shift toward greater use of biologic grafts. At the least, gynecologic surgeons should appreciate the differences between the two types of materials.

In the meantime, transvaginal placement of synthetic mesh should be used carefully and sparingly, with proper attention paid to patient selection and technique to reduce as much as possible the risk of erosion and pain.

In either case, more attention should be paid to the prevention of postoperative infections. Postoperative infection is an underappreciated risk with pelvic reconstructive surgery overall, and the use of synthetic mesh significantly increases this risk. Biologics are safer from an infection standpoint, but proper prevention – including evaluating each patient’s vaginal microflora immediately preoperatively and treating patients accordingly – is important for any surgery.

My advice on synthetics

Selecting patients for POP repair with no mesh, biologic mesh, or synthetic mesh requires thorough patient counseling. This is best done over multiple visits, with the patient reviewing information and coming back for a subsequent visit 1-2 weeks later with questions. She must be prepared psychologically and have realistic expectations.

In its 2011 safety communication, the FDA stated that the main role for mesh with POP repair is in the anterior compartment, and that traditional apical or posterior repair with mesh does not appear to provide any added benefit, compared with traditional surgery without mesh. Rectocele repair should not preclude the use of mesh, however, especially when a prior nonmesh repair has failed. For a patient with a small rectocele, I would advise repair with native tissue, and a second surgery with augmentation if the initial repair fails.

Synthetic mesh should be reserved for patients who have had multiple failures with traditional repairs and who are not sexually active. Sexual behavior is key to the decision-making process I undertake with my patients because synthetic mesh can cause a loss of elasticity in the vagina and consequent dyspareunia. When synthetic meshes are selected, the surgeon should use a minimal amount of material to cover as small an area as possible. It should not be used concomitantly in both the anterior and posterior compartments, as the risk of mesh contraction, rigidity, and vaginal shrinkage is too great.

Incisions in a mesh-augmented anterior or posterior repair should be 3-4 mm thick, passing through the full thickness of the vagina. Posterior compartment incisions should be kept as small in length as possible to reduce the risk of erosion/exposure and hematoma. In the anterior compartment, for similar reasons, surgeons are increasingly moving toward using small semilunar incisions.

In addition to the well-reported risks of erosion, exposure, and extrusion, synthetic meshes pose a problem from an infection point of view. Not uncommonly, synthetic grafts are found upon removal to be covered with biofilms – matrices produced by bacteria or fungi that colonize the material and house the organisms. Biofilm formation can lead to both acute, significant infection and long-term chronic infection; it also can result in metastatic infection if the biofilm breaks off, fragments, and is transported to other areas of the body.

Minimizing infection risk

Biofilms have been known and studied for some time, but there is growing appreciation for the role they play in infections that are chronic, recurrent, or hard to detect and treat. It has been shown, for instance, that patients with recurrent bacterial vaginosis have Gardnerella vaginalis–generated biofilms that house the bacteria and keep it from being adequately penetrated by white blood cells or antibiotics.

Ongoing research is looking for agents to break down biofilms so that antibiotics can reach the infectious organisms embedded within them. At the current time, we do not have any tools available, other than the benefit of understanding how biofilms form, work, and can be prevented. Biofilms can form on a variety of surfaces, synthetic or natural, but clearly, permanent synthetic meshes are more likely to house biofilms than are biologic meshes.

In any case, every patient undergoing POP repair – any surgery, for that matter – should be evaluated prior to the procedure to determine if she is at higher risk of infection. The patient’s vaginal microflora should be evaluated, and conditions such as bacterial vaginosis or aerobic vaginitis should be treated presurgically to reduce her risk of postoperative infection.

Infections rates for POP surgery are not published, to my knowledge, but there is reason to believe the rate is substantive (the infection rate associated with hysterectomy, depending on the population, is 5%-9%, and we do know that most postsurgical pelvic infections are derived from the vaginal microflora.

I also advocate checking the vaginal pH in the operating room before the vagina is prepped. In my surgeries, if the pH is 4.5 or lower, a standard regimen for antibiotic prophylaxis (1-2 g cefazolin) is administered. If the pH is greater than 4.5, then 500 mg metronidazole is added to this standard regimen. This covers pathogenic obligate anaerobes, whose growth is favored in an environment with a higher pH. Antibiotic prophylaxis should be administered one time only.

It is important to recognize as early as possible the patient who is developing an infection or has an infection. There are no definitive signs of developing or early infection. Therefore, any patient who develops postoperative fever (101°F or higher) and has a pulse rate of 100 or higher and an elevated WBC count should be evaluated (physical examination including a pelvic exam). It is important to rule out infection involving the respiratory system, urinary tract, and pelvis.

If there is no evidence of infection, further observation is acceptable. If there is strong suspicion of infection, further evaluation is warranted (ultrasound or CT scan) and broad-spectrum antibiotics should be administered. The patient should be evaluated daily to determine the response to treatment.

Contrary to popular belief, some infections (such as group A streptococcus, group B streptococcus, Escherichia coli) can set in early, within 24-48 hours after surgery.

My experience with biologics

Pelvic reconstructive surgeons became interested in biologic material because both animal studies and clinical experience in other surgical areas, such as hernia repair, have demonstrated a high degree of neovascularization and reepithelialization at the implantation area. When non–cross-linked biologic material is implanted onto or near fascia, new fascia is generated. When it is placed at the site of skin dissection, skin is regenerated. Over 3-6 months, the graft materials break down and are excreted from the body. The risks of complications and infection with non–cross-linked biologic meshes are low in comparison with the synthetic nonabsorbable meshes.

Biologic materials that are cross linked, or treated in an effort to improve strength and durability, tend to have inadequate elasticity and are not porous enough for adequate transmission of white blood cells and macrophages. Cross-linked biologics also may become encapsulated, which makes them more permanent and prone to erosion and other problems seen with the synthetic graft materials.

The non–cross-linked biologics are porous and do not present a barrier to white blood cells and macrophages. At least one of the available biologics in this category has an active antimicrobial component.

Most importantly, the non–cross-linked biologic materials give us much of what we are trying to achieve with augmentation, which is not to have a permanent prosthetic device but rather an extracellular matrix that acts like a cluster of stem cells, stimulating the body to regenerate tissue at the site of implantation.

I have used biologic mesh in approximately 200 surgeries over the past 5 years; many of these surgeries have been POP repairs. My success rate in terms of anatomic outcome and symptom resolution (anecdotally, per nonrandomized evaluation) has been about 85%. I have not hesitated to place biologic mesh concomitantly in both the anterior and posterior compartments, and I have used it to lengthen the vagina. I have not seen any infection or any rejection or allergic issues, and there have been no cases of erosion/exposure.

On occasion, a suture migrates through the vaginal epithelium and creates chronic discharge and/or pain. When the granulation tissue and the suture are both removed, the patient’s symptoms resolve. I have had two patients in whom the suture line has spontaneously opened along the anterior-posterior wall. In both patients, the vaginal discharge resolved once the tissue reepithelialized in 6-8 weeks.

Many patients today tell me immediately in their initial visit that they do not want mesh. It takes some time and thorough explanation to help each patient understand that adverse outcomes are associated mainly with the synthetic meshes, and that biologic materials are worth considering.

Dr. Faro is professor and vice chairman of ob.gyn. at Lyndon Baines Johnson Hospital and professor of obstetrics, gynecology, and reproductive sciences at the University of Texas, both in Houston. He has led infectious disease sections at Baylor College of Medicine and Louisiana State University, is a past president of the Infectious Diseases Society for Obstetrics and Gynecology, has published on postoperative and other infections, and has otherwise been an expert and leader in this realm of gynecologic care. *Dr. Faro is a scientific advisor for the research arm of Medical Diagnostic Laboratories in Hamilton, N.J. 

*CORRECTION (11/25/13): A previous version of this story reported an incorrect financial disclosure of Dr. Sebastian Faro. This article has been updated.

Adverse events associated with the use of synthetic mesh in pelvic organ prolapse (POP) reparative surgery – and the Food and Drug Administration’s safety communication in 2011 warning physicians and patients about transvaginal placement of mesh for the repair of POP and stress urinary incontinence – have had a significant impact on gynecologic surgery.

Many physicians have become reluctant to use synthetic mesh products because of the risks of mesh erosion, exposure, pain and dyspareunia, and litigation. Patients also are concerned or even alarmed by reported risks. Moreover, some manufacturers have become increasingly concerned with the production of mesh products for POP repair, lessening the availability of synthetic mesh, and possibly some biologic mesh as well, for POP reparative surgery. Overall, the future of mesh augmentation in POP repair is uncertain.

Vaginal mesh procedures had surged in the decade prior to 2011 despite the lack of good randomized studies to determine whether mesh augmentation was truly efficacious. And unfortunately, the FDA has grouped synthetic and biologic material together in its reviews and notices of mesh products for POP repair. Not classifying and investigating them separately can mislead patients and hinder the development of randomized controlled trials needed to determine if augmentation with biologic material is truly superior to traditional POP repair using native tissue.

Comparing biologic mesh products to synthetic materials for pelvic organ prolapse repairs is like comparing apples to oranges: Synthetic mesh is permanent, while most biologics break down and remain in the body no longer than 6 months. From the standpoint of complications, this gives biologic materials an advantage. In my practice, biologic grafts have not eroded or caused pain, dyspareunia, or postoperative infections in any of my patients who have had surgical repair for POP.

There remains a real need for augmentation of weakened collagen tissue in the repair of POP. The native tissue in these patients is faulty tissue. Without reinforcement of defective tissue, we cannot expect excellent repairs. Data from nonrandomized studies have borne this out. When I talk with my patients about the options for surgical correction of POP, I tell them that success rates without the use of any augmentation are low, and that only about 60% of patients achieve a satisfactory result with traditional repairs.

Increasingly, I and other gynecologic surgeons are having success with biologic materials in our POP repairs. Efficacy needs to be measured in well-controlled randomized clinical trials, but at this point it appears anecdotally and from nonrandomized case reports that we can achieve good anatomic outcomes – upwards of 80% success rates – with biologic grafts, without the complications of synthetic mesh.

A recent survey of members of the American Urogynecologic Society shows that the use of synthetic mesh in transvaginal POP surgery decreased significantly after the 2011 FDA safety update, while there was no significant change in the use of biologic graft for POP (Female Pelvic Med. Reconstr. Surg 2013;19:191-8). It may be that the tide will shift toward greater use of biologic grafts. At the least, gynecologic surgeons should appreciate the differences between the two types of materials.

In the meantime, transvaginal placement of synthetic mesh should be used carefully and sparingly, with proper attention paid to patient selection and technique to reduce as much as possible the risk of erosion and pain.

In either case, more attention should be paid to the prevention of postoperative infections. Postoperative infection is an underappreciated risk with pelvic reconstructive surgery overall, and the use of synthetic mesh significantly increases this risk. Biologics are safer from an infection standpoint, but proper prevention – including evaluating each patient’s vaginal microflora immediately preoperatively and treating patients accordingly – is important for any surgery.

My advice on synthetics

Selecting patients for POP repair with no mesh, biologic mesh, or synthetic mesh requires thorough patient counseling. This is best done over multiple visits, with the patient reviewing information and coming back for a subsequent visit 1-2 weeks later with questions. She must be prepared psychologically and have realistic expectations.

In its 2011 safety communication, the FDA stated that the main role for mesh with POP repair is in the anterior compartment, and that traditional apical or posterior repair with mesh does not appear to provide any added benefit, compared with traditional surgery without mesh. Rectocele repair should not preclude the use of mesh, however, especially when a prior nonmesh repair has failed. For a patient with a small rectocele, I would advise repair with native tissue, and a second surgery with augmentation if the initial repair fails.

Synthetic mesh should be reserved for patients who have had multiple failures with traditional repairs and who are not sexually active. Sexual behavior is key to the decision-making process I undertake with my patients because synthetic mesh can cause a loss of elasticity in the vagina and consequent dyspareunia. When synthetic meshes are selected, the surgeon should use a minimal amount of material to cover as small an area as possible. It should not be used concomitantly in both the anterior and posterior compartments, as the risk of mesh contraction, rigidity, and vaginal shrinkage is too great.

Incisions in a mesh-augmented anterior or posterior repair should be 3-4 mm thick, passing through the full thickness of the vagina. Posterior compartment incisions should be kept as small in length as possible to reduce the risk of erosion/exposure and hematoma. In the anterior compartment, for similar reasons, surgeons are increasingly moving toward using small semilunar incisions.

In addition to the well-reported risks of erosion, exposure, and extrusion, synthetic meshes pose a problem from an infection point of view. Not uncommonly, synthetic grafts are found upon removal to be covered with biofilms – matrices produced by bacteria or fungi that colonize the material and house the organisms. Biofilm formation can lead to both acute, significant infection and long-term chronic infection; it also can result in metastatic infection if the biofilm breaks off, fragments, and is transported to other areas of the body.

Minimizing infection risk

Biofilms have been known and studied for some time, but there is growing appreciation for the role they play in infections that are chronic, recurrent, or hard to detect and treat. It has been shown, for instance, that patients with recurrent bacterial vaginosis have Gardnerella vaginalis–generated biofilms that house the bacteria and keep it from being adequately penetrated by white blood cells or antibiotics.

Ongoing research is looking for agents to break down biofilms so that antibiotics can reach the infectious organisms embedded within them. At the current time, we do not have any tools available, other than the benefit of understanding how biofilms form, work, and can be prevented. Biofilms can form on a variety of surfaces, synthetic or natural, but clearly, permanent synthetic meshes are more likely to house biofilms than are biologic meshes.

In any case, every patient undergoing POP repair – any surgery, for that matter – should be evaluated prior to the procedure to determine if she is at higher risk of infection. The patient’s vaginal microflora should be evaluated, and conditions such as bacterial vaginosis or aerobic vaginitis should be treated presurgically to reduce her risk of postoperative infection.

Infections rates for POP surgery are not published, to my knowledge, but there is reason to believe the rate is substantive (the infection rate associated with hysterectomy, depending on the population, is 5%-9%, and we do know that most postsurgical pelvic infections are derived from the vaginal microflora.

I also advocate checking the vaginal pH in the operating room before the vagina is prepped. In my surgeries, if the pH is 4.5 or lower, a standard regimen for antibiotic prophylaxis (1-2 g cefazolin) is administered. If the pH is greater than 4.5, then 500 mg metronidazole is added to this standard regimen. This covers pathogenic obligate anaerobes, whose growth is favored in an environment with a higher pH. Antibiotic prophylaxis should be administered one time only.

It is important to recognize as early as possible the patient who is developing an infection or has an infection. There are no definitive signs of developing or early infection. Therefore, any patient who develops postoperative fever (101°F or higher) and has a pulse rate of 100 or higher and an elevated WBC count should be evaluated (physical examination including a pelvic exam). It is important to rule out infection involving the respiratory system, urinary tract, and pelvis.

If there is no evidence of infection, further observation is acceptable. If there is strong suspicion of infection, further evaluation is warranted (ultrasound or CT scan) and broad-spectrum antibiotics should be administered. The patient should be evaluated daily to determine the response to treatment.

Contrary to popular belief, some infections (such as group A streptococcus, group B streptococcus, Escherichia coli) can set in early, within 24-48 hours after surgery.

My experience with biologics

Pelvic reconstructive surgeons became interested in biologic material because both animal studies and clinical experience in other surgical areas, such as hernia repair, have demonstrated a high degree of neovascularization and reepithelialization at the implantation area. When non–cross-linked biologic material is implanted onto or near fascia, new fascia is generated. When it is placed at the site of skin dissection, skin is regenerated. Over 3-6 months, the graft materials break down and are excreted from the body. The risks of complications and infection with non–cross-linked biologic meshes are low in comparison with the synthetic nonabsorbable meshes.

Biologic materials that are cross linked, or treated in an effort to improve strength and durability, tend to have inadequate elasticity and are not porous enough for adequate transmission of white blood cells and macrophages. Cross-linked biologics also may become encapsulated, which makes them more permanent and prone to erosion and other problems seen with the synthetic graft materials.

The non–cross-linked biologics are porous and do not present a barrier to white blood cells and macrophages. At least one of the available biologics in this category has an active antimicrobial component.

Most importantly, the non–cross-linked biologic materials give us much of what we are trying to achieve with augmentation, which is not to have a permanent prosthetic device but rather an extracellular matrix that acts like a cluster of stem cells, stimulating the body to regenerate tissue at the site of implantation.

I have used biologic mesh in approximately 200 surgeries over the past 5 years; many of these surgeries have been POP repairs. My success rate in terms of anatomic outcome and symptom resolution (anecdotally, per nonrandomized evaluation) has been about 85%. I have not hesitated to place biologic mesh concomitantly in both the anterior and posterior compartments, and I have used it to lengthen the vagina. I have not seen any infection or any rejection or allergic issues, and there have been no cases of erosion/exposure.

On occasion, a suture migrates through the vaginal epithelium and creates chronic discharge and/or pain. When the granulation tissue and the suture are both removed, the patient’s symptoms resolve. I have had two patients in whom the suture line has spontaneously opened along the anterior-posterior wall. In both patients, the vaginal discharge resolved once the tissue reepithelialized in 6-8 weeks.

Many patients today tell me immediately in their initial visit that they do not want mesh. It takes some time and thorough explanation to help each patient understand that adverse outcomes are associated mainly with the synthetic meshes, and that biologic materials are worth considering.

Dr. Faro is professor and vice chairman of ob.gyn. at Lyndon Baines Johnson Hospital and professor of obstetrics, gynecology, and reproductive sciences at the University of Texas, both in Houston. He has led infectious disease sections at Baylor College of Medicine and Louisiana State University, is a past president of the Infectious Diseases Society for Obstetrics and Gynecology, has published on postoperative and other infections, and has otherwise been an expert and leader in this realm of gynecologic care. *Dr. Faro is a scientific advisor for the research arm of Medical Diagnostic Laboratories in Hamilton, N.J. 

*CORRECTION (11/25/13): A previous version of this story reported an incorrect financial disclosure of Dr. Sebastian Faro. This article has been updated.

Adverse events associated with the use of synthetic mesh in pelvic organ prolapse (POP) reparative surgery – and the Food and Drug Administration’s safety communication in 2011 warning physicians and patients about transvaginal placement of mesh for the repair of POP and stress urinary incontinence – have had a significant impact on gynecologic surgery.

Many physicians have become reluctant to use synthetic mesh products because of the risks of mesh erosion, exposure, pain and dyspareunia, and litigation. Patients also are concerned or even alarmed by reported risks. Moreover, some manufacturers have become increasingly concerned with the production of mesh products for POP repair, lessening the availability of synthetic mesh, and possibly some biologic mesh as well, for POP reparative surgery. Overall, the future of mesh augmentation in POP repair is uncertain.

Vaginal mesh procedures had surged in the decade prior to 2011 despite the lack of good randomized studies to determine whether mesh augmentation was truly efficacious. And unfortunately, the FDA has grouped synthetic and biologic material together in its reviews and notices of mesh products for POP repair. Not classifying and investigating them separately can mislead patients and hinder the development of randomized controlled trials needed to determine if augmentation with biologic material is truly superior to traditional POP repair using native tissue.

Comparing biologic mesh products to synthetic materials for pelvic organ prolapse repairs is like comparing apples to oranges: Synthetic mesh is permanent, while most biologics break down and remain in the body no longer than 6 months. From the standpoint of complications, this gives biologic materials an advantage. In my practice, biologic grafts have not eroded or caused pain, dyspareunia, or postoperative infections in any of my patients who have had surgical repair for POP.

There remains a real need for augmentation of weakened collagen tissue in the repair of POP. The native tissue in these patients is faulty tissue. Without reinforcement of defective tissue, we cannot expect excellent repairs. Data from nonrandomized studies have borne this out. When I talk with my patients about the options for surgical correction of POP, I tell them that success rates without the use of any augmentation are low, and that only about 60% of patients achieve a satisfactory result with traditional repairs.

Increasingly, I and other gynecologic surgeons are having success with biologic materials in our POP repairs. Efficacy needs to be measured in well-controlled randomized clinical trials, but at this point it appears anecdotally and from nonrandomized case reports that we can achieve good anatomic outcomes – upwards of 80% success rates – with biologic grafts, without the complications of synthetic mesh.

A recent survey of members of the American Urogynecologic Society shows that the use of synthetic mesh in transvaginal POP surgery decreased significantly after the 2011 FDA safety update, while there was no significant change in the use of biologic graft for POP (Female Pelvic Med. Reconstr. Surg 2013;19:191-8). It may be that the tide will shift toward greater use of biologic grafts. At the least, gynecologic surgeons should appreciate the differences between the two types of materials.

In the meantime, transvaginal placement of synthetic mesh should be used carefully and sparingly, with proper attention paid to patient selection and technique to reduce as much as possible the risk of erosion and pain.

In either case, more attention should be paid to the prevention of postoperative infections. Postoperative infection is an underappreciated risk with pelvic reconstructive surgery overall, and the use of synthetic mesh significantly increases this risk. Biologics are safer from an infection standpoint, but proper prevention – including evaluating each patient’s vaginal microflora immediately preoperatively and treating patients accordingly – is important for any surgery.

My advice on synthetics

Selecting patients for POP repair with no mesh, biologic mesh, or synthetic mesh requires thorough patient counseling. This is best done over multiple visits, with the patient reviewing information and coming back for a subsequent visit 1-2 weeks later with questions. She must be prepared psychologically and have realistic expectations.

In its 2011 safety communication, the FDA stated that the main role for mesh with POP repair is in the anterior compartment, and that traditional apical or posterior repair with mesh does not appear to provide any added benefit, compared with traditional surgery without mesh. Rectocele repair should not preclude the use of mesh, however, especially when a prior nonmesh repair has failed. For a patient with a small rectocele, I would advise repair with native tissue, and a second surgery with augmentation if the initial repair fails.

Synthetic mesh should be reserved for patients who have had multiple failures with traditional repairs and who are not sexually active. Sexual behavior is key to the decision-making process I undertake with my patients because synthetic mesh can cause a loss of elasticity in the vagina and consequent dyspareunia. When synthetic meshes are selected, the surgeon should use a minimal amount of material to cover as small an area as possible. It should not be used concomitantly in both the anterior and posterior compartments, as the risk of mesh contraction, rigidity, and vaginal shrinkage is too great.

Incisions in a mesh-augmented anterior or posterior repair should be 3-4 mm thick, passing through the full thickness of the vagina. Posterior compartment incisions should be kept as small in length as possible to reduce the risk of erosion/exposure and hematoma. In the anterior compartment, for similar reasons, surgeons are increasingly moving toward using small semilunar incisions.

In addition to the well-reported risks of erosion, exposure, and extrusion, synthetic meshes pose a problem from an infection point of view. Not uncommonly, synthetic grafts are found upon removal to be covered with biofilms – matrices produced by bacteria or fungi that colonize the material and house the organisms. Biofilm formation can lead to both acute, significant infection and long-term chronic infection; it also can result in metastatic infection if the biofilm breaks off, fragments, and is transported to other areas of the body.

Minimizing infection risk

Biofilms have been known and studied for some time, but there is growing appreciation for the role they play in infections that are chronic, recurrent, or hard to detect and treat. It has been shown, for instance, that patients with recurrent bacterial vaginosis have Gardnerella vaginalis–generated biofilms that house the bacteria and keep it from being adequately penetrated by white blood cells or antibiotics.

Ongoing research is looking for agents to break down biofilms so that antibiotics can reach the infectious organisms embedded within them. At the current time, we do not have any tools available, other than the benefit of understanding how biofilms form, work, and can be prevented. Biofilms can form on a variety of surfaces, synthetic or natural, but clearly, permanent synthetic meshes are more likely to house biofilms than are biologic meshes.

In any case, every patient undergoing POP repair – any surgery, for that matter – should be evaluated prior to the procedure to determine if she is at higher risk of infection. The patient’s vaginal microflora should be evaluated, and conditions such as bacterial vaginosis or aerobic vaginitis should be treated presurgically to reduce her risk of postoperative infection.

Infections rates for POP surgery are not published, to my knowledge, but there is reason to believe the rate is substantive (the infection rate associated with hysterectomy, depending on the population, is 5%-9%, and we do know that most postsurgical pelvic infections are derived from the vaginal microflora.

I also advocate checking the vaginal pH in the operating room before the vagina is prepped. In my surgeries, if the pH is 4.5 or lower, a standard regimen for antibiotic prophylaxis (1-2 g cefazolin) is administered. If the pH is greater than 4.5, then 500 mg metronidazole is added to this standard regimen. This covers pathogenic obligate anaerobes, whose growth is favored in an environment with a higher pH. Antibiotic prophylaxis should be administered one time only.

It is important to recognize as early as possible the patient who is developing an infection or has an infection. There are no definitive signs of developing or early infection. Therefore, any patient who develops postoperative fever (101°F or higher) and has a pulse rate of 100 or higher and an elevated WBC count should be evaluated (physical examination including a pelvic exam). It is important to rule out infection involving the respiratory system, urinary tract, and pelvis.

If there is no evidence of infection, further observation is acceptable. If there is strong suspicion of infection, further evaluation is warranted (ultrasound or CT scan) and broad-spectrum antibiotics should be administered. The patient should be evaluated daily to determine the response to treatment.

Contrary to popular belief, some infections (such as group A streptococcus, group B streptococcus, Escherichia coli) can set in early, within 24-48 hours after surgery.

My experience with biologics

Pelvic reconstructive surgeons became interested in biologic material because both animal studies and clinical experience in other surgical areas, such as hernia repair, have demonstrated a high degree of neovascularization and reepithelialization at the implantation area. When non–cross-linked biologic material is implanted onto or near fascia, new fascia is generated. When it is placed at the site of skin dissection, skin is regenerated. Over 3-6 months, the graft materials break down and are excreted from the body. The risks of complications and infection with non–cross-linked biologic meshes are low in comparison with the synthetic nonabsorbable meshes.

Biologic materials that are cross linked, or treated in an effort to improve strength and durability, tend to have inadequate elasticity and are not porous enough for adequate transmission of white blood cells and macrophages. Cross-linked biologics also may become encapsulated, which makes them more permanent and prone to erosion and other problems seen with the synthetic graft materials.

The non–cross-linked biologics are porous and do not present a barrier to white blood cells and macrophages. At least one of the available biologics in this category has an active antimicrobial component.

Most importantly, the non–cross-linked biologic materials give us much of what we are trying to achieve with augmentation, which is not to have a permanent prosthetic device but rather an extracellular matrix that acts like a cluster of stem cells, stimulating the body to regenerate tissue at the site of implantation.

I have used biologic mesh in approximately 200 surgeries over the past 5 years; many of these surgeries have been POP repairs. My success rate in terms of anatomic outcome and symptom resolution (anecdotally, per nonrandomized evaluation) has been about 85%. I have not hesitated to place biologic mesh concomitantly in both the anterior and posterior compartments, and I have used it to lengthen the vagina. I have not seen any infection or any rejection or allergic issues, and there have been no cases of erosion/exposure.

On occasion, a suture migrates through the vaginal epithelium and creates chronic discharge and/or pain. When the granulation tissue and the suture are both removed, the patient’s symptoms resolve. I have had two patients in whom the suture line has spontaneously opened along the anterior-posterior wall. In both patients, the vaginal discharge resolved once the tissue reepithelialized in 6-8 weeks.

Many patients today tell me immediately in their initial visit that they do not want mesh. It takes some time and thorough explanation to help each patient understand that adverse outcomes are associated mainly with the synthetic meshes, and that biologic materials are worth considering.

Dr. Faro is professor and vice chairman of ob.gyn. at Lyndon Baines Johnson Hospital and professor of obstetrics, gynecology, and reproductive sciences at the University of Texas, both in Houston. He has led infectious disease sections at Baylor College of Medicine and Louisiana State University, is a past president of the Infectious Diseases Society for Obstetrics and Gynecology, has published on postoperative and other infections, and has otherwise been an expert and leader in this realm of gynecologic care. *Dr. Faro is a scientific advisor for the research arm of Medical Diagnostic Laboratories in Hamilton, N.J. 

*CORRECTION (11/25/13): A previous version of this story reported an incorrect financial disclosure of Dr. Sebastian Faro. This article has been updated.