A versatile dual-channel carbon dioxide (CO₂) insufflator for various CO₂ applications

Abstract

Background

Carbon dioxide (CO₂), with its rapid absorptive nature, has been proven superior to atmospheric air as an insufflating agent in various clinical settings. However, CO₂ insufflation has not gained wide clinical acceptance, mainly because there has been no suitable feeding system. The authors therefore have developed a versatile “dual-channel” CO₂ insufflator that facilitates wider use of CO₂. The objectives of this study were to introduce the authors’ prototype insufflator, to evaluate its safety and performance, and to validate CO₂ application using the prototype.

Methods

The prototype insufflator provides one CO₂ inlet connected to a regular CO₂ gas cylinder and two CO₂ outlets positioned on the front and back of the device, respectively. The CO₂ gas fed from the cylinder is pressure-regulated and divided into two independent conduits inside the device. The front outlet feeds CO₂ gas for pneumoperitoneum at an electronically controlled pressure and flow rate. The back channel supplies CO₂ gas at a fixed flow rate, allowing manual control of insufflation for various purposes. The device was evaluated with canine models.

Results

The prototype was safe and performed well. The CO₂ application (colonoscopy in this series) using the back channel was feasible while intact CO₂ pneumoperitoneum was simultaneously maintained via the front channel. There were no device malfunctions. The serial abdominal x-rays indicated that intraluminal CO₂ insufflation such as that used for CO₂ colonoscopy caused less residual intestinal gas than conventional air insufflation.

Conclusions

The dual-channel CO₂ insufflator enabled two different modes of CO₂ insufflation at the same time from a single CO₂ cylinder. The authors are now improving the prototype to allow safer and wider usage of CO₂ in the operating room.