The Feasibility of Using the Ultravision™ System to Facilitate Low Impact Laparoscopic Surgery for the Treatment of Endometriosis

Background/Introduction: The Ultravision™ System is an FDA-cleared medical device that removes surgical smoke by means of electrostatic precipitation from the visual field during laparoscopic surgical procedures. "Surgical smoke" refers to the suspended particulate matter that is generated as a by-product of the combustion and other processes that are associated with the use of energy-based surgical instruments. Surgical smoke can obscure (partially or totally) the surgeon's view of the operative field and this has obvious safety implications for the patient. In the case of laparoscopic procedures, which are increasing in popularity, the smoke is retained within the "closed abdomen" and this, coupled with the CO2 pneumoperitoneum, presents additional challenges for the surgical team. The Ultravision™ System can therefore be considered an accessory to electrosurgical instruments to clear the surgical smoke generated during their use and as such will only be used when such devices are in use. The ability to operate at under "low impact" laparoscopic conditions has been shown by others to improve clinical outcomes by, for example, reducing post-surgical pain and with smaller incision sizes, improved cosmesis. For the purposes of this study "low impact" is defined as (1) a target pneumoperitoneal pressure of 10mm Hg; and (2) instead of 10mm and/or 12mm ports, the use of 3mm ports and one 5mm port. Using a standard insufflator, the combination of lower pneumoperitoneal pressure and smaller size ports creates visualization challenges for the surgeon due to the difficulty of preventing the buildup of surgical smoke within the abdomen. "Venting" or actively extracting the smoke through a trocar is known to be largely ineffective due to the narrow internal diameter of 3mm trocars, certainly unless the instrument is removed beforehand, which creates additional surgical challenges. Furthermore, operating under lower pressure can cause pneumoperitoneum to be lost upon venting of the smoke. The research question that is posed in this study is whether the Ultravision™ System, due to its unique mode of action which (unlike other smoke management approaches) provides smoke management without needing to extract or exchange CO2, provides effective visual field clearing, thereby facilitating low impact laparoscopic surgery when using a conventional insufflator. In addition, Ultravision™ does not require CO2 removal and replacement to achieve its intended use, thereby minimizing to the greatest extent possible patient CO2 exposure. CO2 is dry (effectively 0% relative humidity) and cold (typically 65F) and exposure is linked to postoperative pain and other adverse consequences such as patient cooling and tissue desiccation. Due its mode of action, Ultravision™ minimizes CO2 exposure to the patient. Laparoscopic surgery for the treatment of endometriosis is a common procedure for the removal of mild to moderate endometriosis. Diathermy is commonly used to remove the lesions which can be extensive, therefore this procedure presents an appropriate surgical procedure for this study. Assessments in terms of surgical field visualization, CO2 consumption, end tidal CO2, patient satisfaction for cosmesis, and postoperative pain will be conducted in order to determine if the Ultravision™ System is effective in enabling laparoscopic surgery under low impact laparoscopic conditions. Adverse event information will be reported. The study is an open label single arm study.

Study Purpose: There are five main study objectives:

1. Demonstrate the feasibility of undertaking low impact laparoscopic surgery for endometriosis when using the Ultravision™ System.
2. Assess the impact of Ultravision on visual field clarity.
3. Determine the ability to complete the procedure while maintaining an abdominal pressure of < 10mmHg.
4. Quantify the consumption of CO2.
5. Collect data on additional clinical outcomes associated with the use of Ultravision and low impact surgery (i.e. end tidal CO2 levels (EtCO2), adverse events, cosmesis outcome, postoperative pain levels and pain medications).

Study Hypothesis: The primary hypothesis being tested in this study is that Ultravision facilitates the utilization of low impact laparoscopic surgery techniques whilst maintaining an adequate visual field throughout the procedure with low demand for CO2 replenishment to maintain pneumoperitoneal pressure. Study Population The study will enroll patients indicated for laparoscopic surgery to treat endometriosis. Patients must meet all inclusion/exclusion criteria.

Study Design: This is a prospective single arm study. The study will enroll 20 patients. Comparisons to prior clinical trials and published literature will be made to assess the relative significance of the study results.