An experimental model of cellular aerosolization during laparoscopic surgery

Laparoscopic surgery for cancer has led to the unwelcome occurrence of malignant seeding of port sites. It is hypothesized that this seeding may be a result of aerosolization and forced egress of cells from the peritoneum as a result of pneumoperitoneum. The purpose of this study was to develop a model that would allow for future investigations of cellular aerosolization. Six swine were anesthetized, intubated, and ventilated. A port was placed in the midline and the abdomen insufflated. After insufflation a 14-gauge angiocath was placed in the abdomen through a separate site and attached to a closed system that allowed escaping air to bubble through 3 ml of saline. Intraabdominal pressure was serially increased at 30-min intervals to 8, 10, 12, 14, 16, and 18 mm Hg, and separate saline samples were collected at each interval. Saline samples were centrifuged, and epithelial cells were counted by direct vision and Giemsa staining. Epithelial cells were recovered at all levels of pneumoperitoneum. There was a moderate correlation between the level of pneumoperitoneum and the number of cells collected (r = 0.61, p < 0.19). Results of this study suggest that during pneumoperitoneum there is an ongoing egress of aerosolized cells from the abdomen. Application of this model may aid in future study of aerosolization of cancer cells during laparoscopic surgery.