In Vitro Leakage Testing of Tissue Containment Bags When Subjected to Power Morcellation Forces.

STUDY OBJECTIVE: To determine the ability of tissue containment systems to prevent leakage of cancer cell surrogates when subjected to forces encountered during power morcellation procedures. DESIGN: In vitro study. SETTING: Medical device research laboratory. INTERVENTIONS: Samples from 7 different legally marketed tissue containment bags (1 of which is indicated for power morcellation) were subjected to dye and bacteriophage penetration tests at pressures ranging from 0.5 to 50 times the insufflation pressure. The minimum pressure required to cause bag leakage was measured. Subsequently, the morcellation leakage safety factor for each bag was determined as the ratio of the minimum leakage pressure of the bag to the total pressure contributed from insufflation pressure and mechanical forces acting during the power morcellation procedure. MEASUREMENT AND MAIN RESULTS: The leakage performance of the bags varied markedly from brand to brand. No correlation was found between leakage pressure and the bag material or the total bag thickness. The leakage pressures ranged from 26 mmHg to >1293 mmHg for the 7 bags, and safety factors ranged from 1 to 50 when only the insufflation pressure was considered. However, if the morcellation forces were included in the calculation, the safety factor dropped by 6-fold for all brands and dropped below 1, indicating likelihood of leakage, for 2 of the 7 brands. CONCLUSION: This study provides a mechanism for more realistically simulating the conditions experienced by containment bags during morcellation and quantifying the level of safety provided by the bags.

Mechanical and leakage integrity testing considerations for evaluating the performance of tissue containment systems.

Tissue containment systems (TCS) are medical devices that may be used during morcellation procedures during minimally invasive laparoscopic surgery. TCS are not new devices but their use as a potential mitigation for the spread of occult malignancy during laparoscopic power morcellation of fibroids and/or the uterus has been the subject of interest following reports of upstaging of previously undetected sarcoma in women who underwent a laparoscopic hysterectomy. Development of standardized test methods and acceptance criteria to evaluate the safety and performance of these devices will speed development, allowing for more devices to benefit patients. As a part of this study, a series of preclinical experimental bench test methods were developed to evaluate the mechanical and leakage performance of TCS that may be used in power morcellation procedures. Experimental tests were developed to evaluate mechanical integrity, e.g., tensile, burst, puncture, and penetration strengths for the TCS, and leakage integrity, e.g., dye and microbiological leakage (both acting as surrogates for blood and cancer cells) through the TCS. In addition, to evaluate both mechanical integrity and leakage integrity as a combined methodology, partial puncture and dye leakage was conducted on the TCS to evaluate the potential for leakage due to partial damage caused by surgical tools. Samples from 7 different TCSs were subjected to preclinical bench testing to evaluate leakage and mechanical performance. The performance of the TCSs varied significantly between different brands. The leakage pressure of the TCS varied between 26 and > 1293 mmHg for the 7 TCS brands. Similarly, the tensile force to failure, burst pressure, and puncture force varied between 14 and 80 MPa, 2 and 78 psi, and 2.5 N and 47 N, respectively. The mechanical failure and leakage performance of the TCS were different for homogeneous and composite TCSs. The test methods reported in this study may facilitate the development and regulatory review of these devices, may help compare TCS performance between devices, and increase provider and patient accessibility to improved tissue containment technologies.

Contemporary concepts in hernia prevention: Selected proceedings from the 2017 International Symposium on Prevention of Incisional Hernias.

Incisional hernia is a frequent complication of midline laparotomy and enterostomal creation and is associated with high morbidity, decreased quality of life, and high costs. The International Symposium on Incisional Hernia Prevention was held October 19-20, 2017, at the InterContinental Hotel in San Francisco, CA, hosted by the Department of Surgery, University of California, San Francisco. One hundred and three attendees included general and plastic surgeons from 9 countries, including principal participants for several of the seminal studies in the field. Over the course of the 2-day meeting, there were 38 oral presentations, 3 keynote lectures, and 2 panel discussions. The Symposium was a combination of new information but also a comprehensive review of the existing data so as to assess the current state of the field and to set the stage for future research. Further, the Symposium sought to increase awareness and thus emphasize the importance of preventing the formation of incisional and enterostomal hernias.