Instrument usage in laparoscopic gynecologic surgery: a prospective clinical trial

The influence of prolonged instrument manipulation on gas leakage through trocars

BACKGROUND

During laparoscopic surgery, CO2 insufflation gas could leak from the intra-abdominal cavity into the operating theater. Medical staff could therefore be exposed to hazardous substances present in leaked gas. Although previous studies have shown that leakage through trocars is a contributing factor, trocar performance over longer periods remains unclear. This study investigates the influence of prolonged instrument manipulation on gas leakage through trocars.

METHODS

Twenty-five trocars with diameters ranging from 10 to 15 mm were included in the study. An experimental model was developed to facilitate instrument manipulation in a trocar under loading. The trocar was mounted to a custom airtight container insufflated with CO2 to a pressure of 15 mmHg, similar to clinical practice. A linear stage was used for prolonged instrument manipulation. At the same time, a fixed load was applied radially to the trocar cannula to mimic the reaction force of the abdominal wall. Gas leakage was measured before, after, and during instrument manipulation.

RESULTS

After instrument manipulation, leakage rates per trocar varied between 0.0 and 5.58 L/min. No large differences were found between leakage rates before and after prolonged manipulation in static and dynamic measurements. However, the prolonged instrument manipulation did cause visible damage to two trocars and revealed unintended leakage pathways in others that can be related to production flaws.

CONCLUSION

Prolonged instrument manipulation did not increase gas leakage rates through trocars, despite damage to some individual trocars. Nevertheless, gas leakage through trocars occurs and is caused by different trocar-specific mechanisms and design issues.

Sonographic features of adenomyosis correlated with clinical symptoms and intraoperative findings: a case-control study

PURPOSE

Adenomyosis is a common disease of females during their reproductive age. As of today, histologic examination of the uterus after hysterectomy constitutes the gold standard for diagnosis. The aim of this study was to determine the validity of sonographic, hysteroscopic, and laparoscopic criteria for the diagnosis of the disease.

METHODS

This study included data collected from 50 women in the reproductive age of 18-45 years, who underwent a laparoscopic hysterectomy in the gynecology department of the Saarland University Hospital in Homburg between 2017 and 2018. The patients with adenomyosis were compared with a healthy control group.

RESULTS

We collected data of anamnesis, sonographic criteria, hysteroscopic criteria and laparoscopic criteria and compared it with the postoperative histological results. A total 25 patients were diagnosed with adenomyosis postoperatively. For each of these; at least three sonographic diagnostical criteria for adenomyosis were found compared with a maximum of two for the control group.

CONCLUSION

This study demonstrated an association between pre- and intraoperative signs of adenomyosis. In this way, it shows a high diagnostic accuracy of the sonographic examination as a pre-operative diagnostic method of the adenomyosis.

Hybrid argon plasma coagulation (HybridAPC) versus sharp excision for the treatment of endometriosis: a prospective randomized clinical trial

PURPOSE

Endometriosis is a benign, but potentially serious gynaecological condition in terms of abdominal pain and impaired fertility. Laparoscopic excision techniques are considered the therapeutic standard. HybridAPC is presented as a novel technique for the non-contact thermal ablation of peritoneal endometriosis with simultaneous protection of the underlying thermosensitive structures by creating a needle-free elevated fluid cushion which enables a safer exposure and distance, as well as potentially improved peritoneal conditioning prior to APC.

METHODS

In this prospective randomized clinical trial, 39 patients with 132 superficial endometriotic lesions in total were treated with HybridAPC or sharp excision in an initial laparoscopic procedure according to randomization. In a second-look laparoscopy, adhesion formation was rated macroscopically. Histologic samples were taken from previously treated areas for evaluation of eradication rate.

RESULTS

The eradication rate was not significantly different between HybridAPC treatment and sharp excision (65 vs. 81%, p = .55). Adhesions formed in 5% of HybridAPC-treated lesions and in 10% after sharp excision (p = .49). HybridAPC treatment was significantly faster than sharp excision (69 vs. 106 s, p < .05). No intra- and postoperative complications were registered.

CONCLUSION

This clinical trial demonstrates the feasibility of this novel surgical technique with a promising impact on adhesion prevention. Compared to sharp excision, HybridAPC is likely to be a safe, tissue-preserving, and fast method for the treatment of peritoneal endometriosis.

Mechanical Intelligence (MI): A Bioinspired Concept for Transforming Engineering Design

Despite significant scientific advances in the past decades, most structures around us are static and ironically outdated from a technological perspective. Static structures have limited efficiency and durability and typically perform only a single task. Adaptive structures, in contrast, adjust to different conditions, tasks, and functions. They not only offer multi-functionality but also enhanced efficiency and durability. Despite their obvious advantages over conventional structures, adaptive structures have only been limitedly used in everyday life applications. This is because adaptive structures often require sophisticated sensing, feedback, and controls, which make them costly, heavy, and complicated. To overcome this problem, here the concept of Mechanical Intelligence (MI) is introduced to promote the development of engineering systems that adapt to circumstances in a passive-automatic way. MI will offer a new paradigm for designing structural components with superior capabilities. As adaptability has been rewarded throughout evolution, nature provides one of the richest sources of inspiration for developing adaptive structures. MI explores nature-inspired mechanisms for automatic adaptability and translates them into a new generation of mechanically intelligent components. MI structures, presenting widely accessible bioinspired solutions for adaptability, will facilitate more inclusive and sustainable industrial development, reflective of Goal 9 of the 2030 Agenda for Sustainable Development.

Quantitative Comparison of Surgical Device Usage in Laparoscopic Gastrectomy Between Surgeons' Skill Levels: an Automated Analysis Using a Neural Network

BACKGROUND

Whether surgical device usage in laparoscopic gastrectomy differs with respect to operator's skill levels is unknown. Further, device usage analysis using artificial intelligence has not been reported to date. Herein, we compared the patterns of surgical device usage during laparoscopic gastrectomy for gastric cancer among surgeons at different skill levels. The data of device usage was acquired from laparoscopic video recordings using an automated surgical-instrument detection system.

METHODS

In total, 100 video recordings of infrapyloric lymphadenectomy and 33 of D2 suprapancreatic lymphadenectomy during laparoscopic gastrectomy for gastric cancer were analyzed in this retrospective study. The system's accuracy was evaluated by comparing the automatic and the manual usage time. Surgical device usage patterns were compared between qualified and nonqualified surgeons of The Japan Society for Endoscopic Surgery Endoscopic Surgical Skill Qualification System.

RESULTS

For every device, the automatic detection time and manual detection time were consistent with each other. In infrapyloric lymphadenectomy, the usage time proportions of dissector forceps and clip applier were higher among nonqualified operators than among qualified operators (dissector, 5.1% vs. 2.3%, P < 0.001; clip applier, 1.6% vs. 1.3%, P < 0.01). In suprapancreatic lymphadenectomy, the usage time proportions of energy devices, clip applier, and grasper forceps were significantly different (energy devices, 59.6% vs. 50.6%, P < 0.001; clip applier, 1.4% vs. 0.9%, P < 0.001; only grasper forceps; 18.3% vs. 27.9%, P = 0.022).

CONCLUSIONS

Quantitative analysis of laparoscopic device usage using the automated surgical device detection system showed that the patterns of device usage during laparoscopic gastrectomy differed depending on surgeons' skill levels. These differences could suggest how the qualified and nonqualified surgeons performed the procedures.

Characterisation of trocar associated gas leaks during laparoscopic surgery

BACKGROUND

During laparoscopy, the abdominal cavity is insufflated with carbon dioxide (CO₂) that could become contaminated with viruses and surgical smoke. Medical staff is potentially exposed when this gas leaks into the operating room through the instruments and past trocar valves. No detailed studies currently exist that have quantified these leakage pathways. Therefore, the goal of this study was to quantify the gas leakages through trocars and instruments, during minimally invasive procedures.

METHODS

A model of the surgical environment was created, consisting of a rigid container with an interface for airtight clamping of laparoscopic equipment such as trocars and surgical instruments. The model was insufflated to 15 mm Hg using a pressure generator and a pneumotachograph measured the equipment gas leak. A protocol of several use cases was designed to simulate the motions and forces the surgeon exerts on the trocar during surgery.

RESULTS

Twenty-three individual trocars and twenty-six laparoscopic instruments were measured for leakage under the different conditions of the protocol. Trocar leakages varied between 0 L/min and more than 30 L/min, the instruments revealed a range of leakages between 0 L/min and 5.5 L/min. The results showed that leakage performance varied widely between trocars and instruments and that the performance and location of the valves influenced trocar leakage.

CONCLUSIONS

We propose trocar redesigns to overcome specific causes of gas leaks. Moreover, an international testing standard for CO₂ leakage for all new trocars and instruments is needed so surgical teams can avoid this potential health hazard when selecting new equipment.

A Novel Suction-and-Irrigation Laparoscopic Surgical Instrument: Internal Design and Preclinical Performance Evaluation

Objective: Laparoscopic instruments with suction and irrigation functions often lead to tissue damage during removal of the aspirated tissues, owing to the presence of aspiration into the side holes of their catheters. To address this problem, we designed a novel irrigation-and-suction catheter and assessed its preclinical efficacy.

Methods: We made structural improvements to the irrigation-suction catheter to prevent tissue aspiration through its side holes. We ran a simulation program to perform experimental assessments before printing out the catheter tip models using a three-dimensional (3D) printer. Model 1 was the control, and Models 2, 3, and 4 were the improved models. Using these, we performed 10 repetitions of 15-s suction followed by 15-s irrigation, for a total of 5 times per model. We recorded the number of aspirations that occurred through the side holes and analyzed each model using nonparametric methods.

Results: Models 2 and 3 showed fewer aspirations because the velocity and pressure around their side holes were lower than those of Model 1; this was statistically significant. On the other hand, Model 4 had a lesser preventive effect against aspiration due to higher velocity and pressure around its side holes.

Interpretation of Results: We confirmed that side-hole aspiration can be prevented with an internal structure that completely separates the irrigation and suction paths. Even if the irrigation and suction paths are not completely separated, adding a septal structure at the distal end of the catheter may prevent aspiration.

Stop the leak!: Mitigating potential exposure of aerosolized COVID-19 during laparoscopic surgery

BACKGROUND

Viral particles have been shown to aerosolize into insufflated gas during laparoscopic surgery. In the operating room, this potentially exposes personnel to aerosolized viruses as well as carcinogens. In light of circumstances surrounding COVID-19 and a concern for the safety of healthcare professionals, our study seeks to quantify the volumes of gas leaked from dynamic interactions between laparoscopic instruments and the trocar port to better understand potential exposure to surgically aerosolized particles.

METHODS

A custom setup was constructed to simulate an insufflated laparoscopic surgical cavity. Two surgical instrument use scenarios were examined to observe and quantify opportunities for insufflation gas leakage. Both scenarios considered multiple configurations of instrument and trocar port sizes/dimensions: (1) the full insertion and full removal of a laparoscopic instrument from the port and (2) the movement of the scope within the port, recognized as "dynamic interaction", which occurs nearly 100% of the time over the course of any procedure.

RESULTS

For a 5 mm instrument in a 5 mm trocar, the average volume of gas leaked during dynamic interaction and full insertion/removal scenarios were 43.67 and 25.97 mL of gas, respectively. Volume of gas leaked for a 5 mm instrument in a 12 mm port averaged 41.32 mL and 29.47 for dynamic interaction vs. instrument insertion and removal. Similar patterns were shown with a 10 mm instrument in 12 mm port, with 55.68 mL for the dynamic interaction and 58.59 for the instrument insertion/removal.

CONCLUSIONS

Dynamic interactions and insertion/removal events between laparoscopic instruments and ports appear to contribute to consistent leakage of insufflated gas into the OR. Any measures possible taken to reduce OR gas leakage should be considered in light of the current COVID-19 pandemic. Minimizing laparoscope and instrument removal and replacement would be one strategy to mitigate gas leakage during laparoscopic surgery.