KeyLoop retractor for global gasless laparoscopy: evaluation of safety and feasibility in a porcine model.

BACKGROUND: Many surgeons in low- and middle-income countries have described performing surgery using gasless (lift) laparoscopy due to inaccessibility of carbon dioxide and reliable electricity, but the safety and feasibility of the technique has not been well documented. We describe preclinical testing of the in vivo safety and utility of KeyLoop, a laparoscopic retractor system to enable gasless laparoscopy. METHODS: Experienced laparoscopic surgeons completed a series of four laparoscopic tasks in a porcine model: laparoscopic exposure, small bowel resection, intracorporeal suturing with knot tying, and cholecystectomy. For each participating surgeon, the four tasks were completed in a practice animal using KeyLoop. Surgeons then completed these tasks using standard-of-care (SOC) gas laparoscopy and KeyLoop in block randomized order to minimize learning curve effect. Vital signs, task completion time, blood loss and surgical complications were compared between SOC and KeyLoop using paired nonparametric tests. Surgeons completed a survey on use of KeyLoop compared to gas laparoscopy. Abdominal wall tissue was evaluated for injury by a blinded pathologist. RESULTS: Five surgeons performed 60 tasks in 15 pigs. There were no significant differences in times to complete the tasks between KeyLoop and SOC. For all tasks, there was a learning curve with task completion times related to learning the porcine model. There were no significant differences in blood loss, vital signs or surgical complications between KeyLoop and SOC. Eleven surgeons from the United States and Singapore felt that KeyLoop could be used to safely perform several common surgical procedures. No abdominal wall tissue injury was observed for either KeyLoop or SOC. CONCLUSIONS: Procedure times, blood loss, abdominal wall tissue injury and surgical complications were similar between KeyLoop and SOC gas laparoscopy for basic surgical procedures. This data supports KeyLoop as a useful tool to increase access to laparoscopy in low- and middle-income countries.

KeyLoop: Mechanical Retraction of the Abdominal Wall for Gasless Laparoscopy.

Background. Despite favorable outcomes of laparoscopic surgery in high-income countries, its implementation in low- and middle-income countries (LMICs) is challenging given a shortage of consumable supplies, high cost, and risk of power outages. To overcome these barriers, we designed a mechanical retractor that provides vertical tension on the anterior abdominal wall. Methods. The retractor design is anatomically and mathematically optimized to provide exposure similar to traditional gas-based insufflation methods. Anatomical data from computed tomography scans were used to define retractor size. The retractor is constructed of biocompatible stainless steel rods and paired with a table-mounted lifting system to provide 5 degrees of freedom. Structural integrity was assessed through finite element analysis (FEA) and load testing. Functional testing was performed in a laparotomy model. Results. A user guide based on patient height and weight was created to customize retractor size, and 4 retractor sizes were constructed. FEA data using a 13.6 kg mass (15 mm Hg pneumoperitoneum) show a maximum of 30 mm displacement with no permanent deformation. Physical load testing with applied weight from 0 to 13.6 kg shows a maximum of 60 mm displacement, again without permanent deformation. Retraction achieved a 57% larger field of view compared to an unretracted state in a laparotomy model. Conclusions. The KeyLoop retractor maintains structural integrity, is easily sterilized, and can be readily manufactured, making it a viable alternative to traditional insufflation methods. For surgeons and patients in LMICs, the KeyLoop provides a means to increase access to laparoscopic surgery.

Laparoscopic experience and attitudes toward a low-cost laparoscopic system among surgeons in East, Central, and Southern Africa: a survey study.

BACKGROUND: Laparoscopic surgery has become standard of care in high-income countries but is rarely accessible in low- and middle-income countries (LMICs). This study assessed experience with laparoscopy and attitudes toward a low-cost laparoscopic system among surgeons in sub-Saharan Africa. METHODS: A survey assessing current laparoscopic practice and feedback on a low-cost laparoscopic system was administered to attendees of the College of Surgeons of East, Central, and Southern Africa (COSECSA) Scientific Conference between December 4 and December 6, 2019 in Kampala, Uganda. RESULTS: Fifty-six surgeons from 14 countries participated. A majority were male (n = 46, 82%) general surgeons (n = 37, 66%) from tertiary/teaching hospitals (n = 36, 64%). For those with training in laparoscopy (n = 33, 59%), 22 (67%) reported less than 1 year of training and over half (n = 17, 52%) reported 1 month or less. Overall, a minority (n = 21, 38%) used laparoscopy in current practice, with 57% (n = 12) of those performing laparoscopy less than once per week. The most common laparoscopic surgeries performed were cholecystectomy (n = 15), diagnostic laparoscopy (n = 14), and appendectomy (n = 12). Few surgeons were performing more complex cases (n = 5). Barriers to laparoscopy included poor access to training equipment (n = 34, 61%), mentors (n = 33, 59%), laparoscopic equipment (n = 31, 55%), equipment maintenance (n = 25, 45%), access to consumable supplies (n = 21, 38%), and cost (n = 31, 55%). Fifty-two participants (93%) were interested in increasing their use of laparoscopy; the majority felt that a low-cost laparoscope (n = 52, 93%) and lift retractor for gasless laparoscopy (n = 46, 82%) would serve an unmet need in their practice. CONCLUSIONS: While the use of laparoscopy is currently limited in COSECSA countries, there is a significant interest among surgeons to increase implementation. A low-cost, durable laparoscopic system was viewed as a potential solution to the current barriers and could improve implementation in LMICs.

Raloxifene Improves Bone Mechanical Properties in Mice Previously Treated with Zoledronate.

Bisphosphonates represent the gold-standard pharmaceutical agent for reducing fracture risk. Long-term treatment with bisphosphonates can result in tissue brittleness which in rare clinical cases manifests as atypical femoral fracture. Although this has led to an increasing call for bisphosphonate cessation, few studies have investigated therapeutic options for follow-up treatment. The goal of this study was to test the hypothesis that treatment with raloxifene, a drug that has cell-independent effects on bone mechanical material properties, could reverse the compromised mechanical properties that occur following zoledronate treatment. Skeletally mature male C57Bl/6J mice were treated with vehicle (VEH), zoledronate (ZOL), or ZOL followed by raloxifene (RAL; 2 different doses). At the conclusion of 8 weeks of treatment, femora were collected and assessed with microCT and mechanical testing. Trabecular BV/TV was significantly higher in all treated animals compared to VEH with both RAL groups having significantly higher BV/TV compared to ZOL (+21%). All three drug-treated groups had significantly more cortical bone area, higher cortical thickness, and greater moment of inertia at the femoral mid-diaphysis compared to VEH with no difference among the three treated groups. All three drug-treated groups had significantly higher ultimate load compared to VEH-treated animals (+14 to 18%). Both doses of RAL resulted in significantly higher displacement values compared to ZOL-treated animals (+25 to +50%). In conclusion, the current work shows beneficial effects of raloxifene in animals previously treated with zoledronate. The higher mechanical properties of raloxifene-treated animals, combined with similar cortical bone geometry compared to animals treated with zoledronate, suggest that the raloxifene treatment is enhancing mechanical material properties of the tissue.

Safety and efficacy of an implantable device for management of gastroesophageal reflux in lung transplant recipients.

BACKGROUND: Magnetic sphincter augmentation (MSA) is a promising minimally invasive surgical technique for management of gastroesophageal reflux disease (GERD); however, device implantation after transplantation has not been studied and may be concerning in these immunosuppressed patients. We explored the safety of the LINX Reflux Management System (MSA device) for management of GERD following lung transplantation (LTx). METHODS: Lung transplant recipients who underwent LINX implantation at our institution between 2017 and 2019 were followed prospectively in the Reflux Following Lung Transplantation and Associated Treatment Registry. Ambulatory pH testing and acid-suppressing medication use were compared before and after LINX implantation. One-year outcomes and change in pulmonary function were compared between matched LINX and fundoplication groups. RESULTS: Of 17 patients who underwent post-lung transplant LINX implantation, 8 (47.1%) agreed to undergo post-LINX pH testing. Three/eight (37.5%) patients achieved normal esophageal acid exposure time; 14 (82.4%) remained on acid-suppressing medication at one-year under the direction of their transplant teams. One-year patient survival and change in pulmonary function were similar between groups. LINX patients experienced more early side effects. CONCLUSIONS: Use of the LINX MSA device in a cohort of lung transplant recipients at our institution was associated with similar short-term safety compared to traditional fundoplication, however assessment of efficacy was limited. Further investigation is needed to characterize the long-term efficacy of LINX implantation after LTx.

An Accessible Laparoscope for Surgery in Low- and Middle- Income Countries.

Laparoscopic surgery is the standard of care in high-income countries for many procedures in the chest and abdomen. It avoids large incisions by using a tiny camera and fine instruments manipulated through keyhole incisions, but it is generally unavailable in low- and middle-income countries (LMICs) due to the high cost of installment, lack of qualified maintenance personnel, unreliable electricity, and shortage of consumable items. Patients in LMICs would benefit from laparoscopic surgery, as advantages include decreased pain, improved recovery time, fewer wound infections, and shorter hospital stays. To address this need, we developed an accessible laparoscopic system, called the ReadyView laparoscope for use in LMICs. The device includes an integrated camera and LED light source that can be displayed on any monitor. The ReadyView laparoscope was evaluated with standard optical imaging targets to determine its performance against a state-of-the-art commercial laparoscope. The ReadyView laparoscope has a comparable resolving power, lens distortion, field of view, depth of field, and color reproduction accuracy to a commercially available endoscope, particularly at shorter, commonly-used working distances (3-5 cm). Additionally, the ReadyView has a cooler temperature profile, decreasing the risk for tissue injury and operating room fires. The ReadyView features a waterproof design, enabling sterilization by submersion, as commonly performed in LMICs. A custom desktop software was developed to view the video on a laptop computer with a frame rate greater than 30 frames per second and to white balance the image, which is critical for clinical use. The ReadyView laparoscope is capable of providing the image quality and overall performance needed for laparoscopic surgery. This portable low-cost system is well suited to increase access to laparoscopic surgery in LMICs.