Surgical Hernia Mesh: MedSun Small Sample Survey Summary
MedSun: Newsletter #54, November 2010

Survey Topic: Surgical Hernia Mesh
Year Conducted: 2009


Background
There have been several recalls and warning letters sent over the last 5 years to distributors, hospital administrators, and Chief Surgeons to let them know about device defects with surgical mesh. In October 2008, FDA updated its safety information on mesh used in hernia repair. Although the vast majority of adverse event reports received are related to recalled meshes, FDA continues to see reports discussing adverse reactions to mesh including, but not limited to, adhesions, infection, perforation, and injuries to nearby organs, nerves or blood vessels.

In an effort to obtain more information about the use of surgical mesh and clinical outcomes, a survey was conducted with nine clinicians that included general surgeons and operating room personnel. The information that follows is a summary of the interviews.

Summary
When selecting a mesh for hernia repair, respondents said that the size of the hernia and the type of repair needed were the most important factors. About half of the respondents did avoid certain meshes for various reasons such as Dualmesh® or Gore-Tex® because of an increased infection rate and in-growth problems, and Vicryl™ mesh because it doesn’t dissolve. The Prefix® Plug for “virgin” hernias was avoided because it doesn’t cover the area well and can shrink into a meshoma.

Respondents stated they removed mesh infrequently, about 1 out of every 100 procedures, and added that complications were rare. The most common complications warranting removal of the mesh were infection, recurrent hernia, and a fibrotic reaction. Most had not seen complications with one type of mesh more often than with other types. Chronic pain was deemed a significant complication which was mostly attributed to excessive sutures around the mesh, the surgical technique used in inguinal repairs, and fibroblasts growing into the interstices of the mesh.

FDA is pursuing additional avenues to obtain information about the use of mesh in hernia repair.

Small scale surveys are one of many tools the Agency uses to evaluate the public health impact of the potential problems associated with the use of medical devices. Because these surveys utilize a small sample size that is not statistically derived, the results provide only qualitative and not quantitative results. Additionally, FDA continues to receive adverse event reports from its Medical Device Reporting program, and will continue to make use of the literature and other published information. FDA scientific, medical, nursing and engineering staff are made aware of the survey results as needed. If FDA believes a possible public health problem may be emerging from the results of a survey, it will combine those results with data gained from the other sources and may convene an Ad Hoc group of clinical and manufacturing representatives to discuss further actions.

FDA will work with the manufacturers and health care professional organizations to make important information known about medical devices to the clinical community.


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Small Sample Survey Questions

Surgeon Practice

•In your practice, what percentage of cases involve hernia repair? Approximately how many hernia operations do you perform per year?
•What types of hernias do you typically see and repair (i.e. inguinal, ventral)?
•In these cases, how often do you use mesh for the repair? How do you make the decision to use mesh? What would you say is the breakdown of mesh/non-mesh hernia repairs that you perform?
•What operative procedure(s) do you perform using mesh to repair hernias? (i.e., laparoscopic, open procedure?)

Mesh material and design

•What types of mesh do you use most often? For example, polypropylene; PTFE meshes, biologic, others?
•Do you use different designs such as 1-dimensional and 3-dimensional mesh?
•Is the type of mesh you use most often pre-cut or non-pre cut?

Implantation

•With the type of mesh that you use most often, what patient characteristics play a role in mesh selection and use? (i.e., diabetic, obese, male, female)
•What types of mesh do you usually avoid using? And, for what reasons?
•How do you secure mesh? Have you had any problems using the fixation devices?

Explantation

•How often do you have to remove mesh? What types of mesh have you removed most often? And why?
•What are the most common complications you see that warrant removal of the implanted mesh? How often do these complications occur, i.e., 1 out of 10 surgeries, 1 out of 20 surgeries, etc.?
•Have you seen complications with one type of mesh more often than other types?
•Have you seen a difference in complications with pre-cut mesh vs. non pre-cut mesh?
•Do you ever see any complications during the explantation of a particular mesh product?
•Do you ever see adverse events, such as, tissue irritation that may be associated with modified mesh, or have needed to do a revision because of irritated tissue?

Device Performance and Experience

•In your opinion, what types of mesh have resulted in better patient outcomes?
•In your opinion, are patient outcomes dependent upon specific patient characteristics, such as the use of a particular type of mesh in a particular type of patient?
•What do you usually tell your patients about the use of mesh in hernia surgery?
•Prior to using mesh in your patients for hernia repair, how did you learn about mesh repair (i.e. did you receive training during your residency, did you take a course, did you read about the procedure, etc)?
•Do you think the training you received was sufficient?
•How could the training have been improved?

Device Labeling

As you know, FDA clearance is required for marketing a medical device within the US. With respect to surgical mesh, what is your expectation regarding the level of evidence that served as the basis for FDA’s clearance/approval?

FDA’s review of medical devices involves the evaluation of medical device labeling. To what extent have you used or referred to the product labeling that you have used for operations involving mesh?
•If you have seen the labeling, did it meet your needs?
•If you have not seen the labeling, what is your expectation regarding the types of information that should be included in the labeling?

Patient Informed Consent

FDA has heard from patient groups that informed consent regarding the use of mesh products for hernia repair is variable.
•What do you think could be done to better inform patients of the risks/benefits associated with hernia repair using mesh products?
•Do you have any standard consent form you use for these procedures? Do you think that the FDA can play a role in this?

In addition, FDA has also heard that more attention from the perspective of patient informed consent, mesh product manufacturer labeling, and surgeon training should be given to providing more information regarding salvage or removal of implanted mesh used in hernia repair.
•What are your thoughts on this?
•To what extent do you think that FDA and/or professional societies serve to help research and disseminate information about how implanted mesh may be salvaged or retrieved?

Recalls

•How do you typically become aware of recalls? How does your hospital track recalls?




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