Tulip BioMed™, developer of instruments for plastic, aesthetic, and orthopedic surgeries, has released the results of a study that compared the interior surface of its disposable cannulas with the interior surfaces of non-Tulip reusable cannulas postsurgery. The study results show that despite cleaning, residue remains in reusable closed-end cannulas that have been previously used in plastic surgery procedures.

“While we cannot state that any residue that may remain on the interior surface of reusable cannulas, despite cleaning and sterilization, are ‘contaminants,’ these results suggest that there may be the potential for the transfer of protein residue material from one patient to another when reusable cannulas are utilized,” says Richard P. Burgoon, Jr, Tulip BioMed’s president and COO.

The study, which was conducted at the University of California San Diego Medical Center, compared the inner surface of disposable Tulip BioMed 2.1-mm cannulas with the inner surface of several non-Tulip reusable cannulas (3 mm) that were provided to the researchers after use and ready for surgery (that is, cleaned and autoclaved in the customary manner). A scanning electron microscope examined the interior metal surfaces of the cannulas. The surfaces were scanned at multiple resolutions, ranging from 50 to 20,000 times magnification. The interior surface of the disposable cannulas appeared cleaner and smoother compared to the reusable cannulas.

An assessment of the materials remaining on the interior metal surfaces of the reusable cannulas was also conducted using a nuclear magnetic resonance imaging scan. The cannulas were washed with 10 mL phosphate buffered saline and passed through the interior portion of the cannulas using a 10 mL plastic syringe that mimics the force of a typical injector during surgery. The released fluids were then collected in sterile test tubes, centrifuged, and the material at the bottom of the centrifuged tubes was evaluated. All samples showed the presence of nitrogen–hydrogen bonds, suggesting that the material released from the reusable cannulas included organic materials containing amino acids or a protein residue.

[Medical News Today, May 30, 2007]