Valveless Trocar Versus Standard Pneumoperitoneum Insufflation System in Minimally Invasive Surgery: Impact on Postoperative Pain. A Systematic Review and Meta-Analysis

Comparison of AirSeal versus conventional insufflation system for robot-assisted partial nephrectomy: a meta-analysis and systematic review

A systematic review and meta-analysis were performed to investigate the efficacy of the AirSeal Valveless Trocar Needle Insufflation System in robot-assisted partial nephrectomy (RAPN). The study compared the differences in perioperative outcomes between the AirSeal insufflation group (AIS) and the conventional insufflation group (CIS). A systematic search of databases such as PubMed, Embase, Cochrane library, and Web of science was performed to identify studies reporting perioperative outcomes between the AirSeal insufflation group (AIS) and the conventional insufflation group (CIS) in RAPN. The study protocol is registered with PROSPERO (CRD42024524335). The primary outcome was to compare the incidence of subcutaneous emphysema (SCE) and postoperative pain scores between the two approaches. The review included four studies with 379 patients, 194 in the AIS group and 185 in the CIS group. Baseline characteristics of the two groups were similar in all outcomes. SCE was significantly lower in the AIS group than in the CIS group [(OR) 0.30 (0.16, 0.54), p < 0.001]. Postoperative 12-h pain scores were also significantly lower in the AIS group compared to the CIS group [(WMD) - 0.93 (- 1.67, - 1.09), p = 0.014]. Both groups showed a significant reduction in length of hospitalization [(WMD) - 0.12 (- 0.84, 0.60), p = 0.746], thermal ischemia time [(WMD) 4.72 (- 5.71, 15.15), p = 0.375], amount of lost hemoglobin [(WMD) - 0.19 (- 0.53, 0.15), p = 0.284], pneumothorax [(OR) 0.13 (0.02,1.10), p = 0.062], mediastinal emphysema [(OR) 0.55 (0.20, 1.46), p = 0.230], and 4-h pain score [(WMD) - 0.25 (- 1.16, 0.65), p = 0.584]; no significant differences were observed. The incidence of subcutaneous emphysema SCE and 12-h pain scores were significantly lower in the AIS group compared to the CIS group. The AirSeal system demonstrated similar efficacy and a higher safety profile than the conventional insufflation system in robotic-assisted partial nephrectomy; however, due to the lack of a randomized study on the topic, further data are needed.

Effect of heating insufflation tube of AirSeal system on laparoscopic surgery

The AirSeal system (CONMED, NY, USA) can outstandingly keep pneumoperitoneum stable. However, water droplets form on the access port, impairing the performance of comfortable surgical procedures because of the resultant wet surgical field. This study was performed to clarify the mechanism of water droplet formation and to prevent it. Condensation was observed on the AirSeal system. A heater was wrapped around the tri-lumen tube, and the heating effect was assessed. The simulator experiments revealed that condensation formed in the tri-lumen tube and on the wall of the access port. The accumulated weight of the condensation on the wall of the access port was 41.6 g in the Heated group, 138.2 g in the Control group, and 479.4 g in the Cooled group. In the clinical assessment, the accumulated volume of the condensation attached to the inside wall was significantly smaller in the Heated group than in the Unheated group (111.7 g vs. 332.9 g, respectively). We clarified that the volume of condensation attached to the wall of the access port depended on the temperature of the tri-lumen tube. The clinical study revealed that the condensation on the access port was reduced by heating the tri-lumen tube. The development of a novel heating device for the insufflation tube would be effective and useful.

Escape of surgical smoke particles, comparing conventional and valveless trocar systems

BACKGROUND

During minimal access surgery, surgical smoke is produced which can potentially be inhaled by the surgical team, leading to several health risks. This smoke can escape from the abdominal cavity into the operating room due to trocar leakage. The trocars and insufflator that are used during surgery influence gas leakage. Therefore, this study compares particle escape from a valveless (Conmed AirSeal iFS), and a conventional (Karl Storz Endoflator) system.

MATERIALS AND METHODS

Using an in vitro model, a conventional and a valveless trocar system were compared. A protocol that simulated various surgical phases was defined to assess the surgical conditions and particle leakage. Insufflation pressures and instrument diameters were varied as these are known to affect gas leakage.

RESULTS

The conventional trocar leaked during two distinct phases. Removal of the obturator caused a sudden release of particles. During instrument insertion, an average of 211 (IQR 111) particles per second escaped when using the 5 mm diameter instrument. With the 10 mm instrument, 50 (IQR 13) particles per second were measured. With the conventional trocar, a higher abdominal pressure increased particle leakage. The valveless trocar demonstrated a continuously high particle release during all phases. After the obturator was removed, particle escape increased sharply. Particle escape decreased to 1276 (IQR 580) particles per second for the 5 mm instrument insertion, and 1084 (IQR 630) particles per second for 10 mm instrument insertion. With the valveless trocar system, a higher insufflation pressure lowered particle escape.

CONCLUSIONS

This study shows that a valveless trocar system releases more particles into the operating room environment than a conventional trocar. During instrument insertion, the leakage through the valveless system is 6 to 20 times higher than the conventional system. With a valveless trocar, leakage decreases with increasing pressure. With both trocar types leakage depends on instrument diameter.