Background: Intra-abdominal pressure during laparoscopic insufflation with pressurized carbon dioxide (CO₂) gas is strongly influenced by mechanical ventilation. Resulting pressure fluctuations can destabilize the surgical workspace and potentially cause harm associated with high insufflation pressures. To address this, a novel CO₂ insufflator was developed using a radial fan and a gas reservoir to generate and maintain continuously stable insufflation pressures (radial fan-based insufflator, RFBI). This first-in-human study evaluated its safety and feasibility during laparoscopic surgery. Methods: Adults undergoing elective intraperitoneal laparoscopic procedures were included. All procedures were performed using the RFBI and an 11 mm study trocar. Primary outcomes were safety, defined as the absence of serious or harmful adverse device effects (SADEs or ADEs), and feasibility, defined as completing the procedure without switching to a conventional insufflator. Secondary outcomes included pressure stability at the device outlet and documentation of observed events affecting pressure stability (e.g., trocar insertion/repositioning, leaks, suction, etc.). Results: Twelve patients were enrolled, having a total RFBI insufflation time of 35.9 h in seven different laparoscopic procedures. No SADEs occurred. One ADE occurred while inserting a 5 mm instrument into the 11 mm study trocar that resulted in high air leakage, causing temporary loss of surgical workspace but no harm. All procedures were completed without the need to switch to a conventional insufflator. Pressure remained stable at both target pressures of 10 mmHg (median 10.0 mmHg, interquartile range (IQR) 0.12) and 14 mmHg (median 14.0 mmHg, IQR 0.15). The RFBI rapidly re-established the target pressure after observed events affecting stability, without manual intervention or procedural delay. Conclusion: This first-in-human study demonstrates that RFBI technology is safe, feasible, and capable of maintaining stable insufflation pressures across varied adult laparoscopic procedures. Radial fan-based insufflation effectively compensated for pressure fluctuations from ventilation and surgical events, warranting further evaluation of clinical benefits.

Background: Abdominal compliance describes the ease of expansion of the abdominal cavity. Several studies highlighted the importance of monitoring abdominal compliance (C_ab) during the creation of laparoscopic workspace to individualize the insufflation pressure. The lack of validated clinical monitoring tools for abdominal compliance prevents accurate tailoring of insufflation pressure. Oscillometry, also known as the forced oscillation technique (FOT), is currently used to measure respiratory mechanics and has the potential to be adapted for monitoring abdominal compliance. This study aimed to define, develop and evaluate a novel approach which can monitor abdominal compliance during laparoscopy using endoscopic oscillometry. Materials and methods: Endoscopic oscillometry was evaluated in a porcine model for laparoscopy. A custom-built insufflator was developed for applying an oscillatory pressure signal superimposed onto a mean intra-abdominal pressure. This insufflator was used to measure the abdominal compliance at insufflation pressures ranging from 5 to 20 hPa (3.75 to 15 mmHg). The measurements were compared to the static abdominal compliance, which was measured simultaneously with computed tomography imaging. Results: Endoscopic oscillometry recordings and CT images were obtained in 10 subjects, resulting in 76 measurement pairs for analysis. The measured dynamic C_ab ranged between 0.0216 and 0.261 L/hPa while the static C_ab based on the CT imaging ranged between 0.0318 and 0.364 L/hPa. The correlation showed a polynomial relation and the adjusted R-squared was 97.1%. Conclusions: Endoscopic oscillometry can be used to monitor changes in abdominal compliance during laparoscopic surgery, which was demonstrated in this study with a comparison with CT imaging in a porcine laparoscopy model. Use of this technology to personalize the insufflation pressure could reduce the risk of applying excessive pressure and limit the drawbacks of insufflation.