Post-Surgical Respiratory Distress In Cats Associated With Chlorhexidine Surgical Scrubs

This past winter (1996), Dr. Mosley of the LakeviewVeterinaiy Clinic, Mitchell, South Dakota, was seeing post-surgical respiratory distress in cats. The syndrome occured 24-48 hours after surgery and consisted of fever, partial anorexia, serous nasal discharge, and an abnormal respiratory "rattle" that seemed to originate from the larynx and nasal cavities. There were no deaths, and with supportive care the cats recovered in two to five days. A temporary cessation of surgeries combined with a thorough cleansing of the surgical suite and equipment did not resolve the problem. Changes in anesthetic protocols also did not resolve the problem.

Pharyngeal swabs from three different cats were submitted for virus isolation during their respiratory distress; one cat was cultured twice several weeks apart. A virus that was neutralized by antibody to Feline Syncytial Virus was isolated from two different cats. Culture attempts from one cat did not re-isolate the virus. The importance of these viruses relative to the clinical syndrome is doubtful.

A note concerning this problem was posted on the internet (American Association of Veterinary Laboratory Diagnosticians  - List).   Several suggestions were received, but most had already been considered and ruled out. A previous report of adverse reactions to chlorhexidine surgical scrubs was discussed.

The clinic  involved with the current investigation was using Nolvasan Surgical Scrub (Fort Dodge Labs) and all cats with the problem were scrubbed with that 2% chlorhexidine acetate product. The product was not being used to clean endotracheal tubes and the problem had occurred in some cats that had not been intubated. After ceasing use of chlorhexidine surgical scrub, the problem immediately resolved, highly suggestive that this was an adverse reaction to chlorhexidine surgical     scrub,     centered     on     the laryngeal/pharyngeal tissues.

The problem with chlorhexidine in cats has led one company (Solvay) to place warning labels against usage on cats and kittens (Solvahex brand -4% chlorhexidinegluconate).    Fort Dodge Laboratories has not warned against usage in cats as they report the problem is very rare with their product and they suspect individual sensitivity is a factor.

Two routes of exposure are possible. The material can be a residue on endotracheal tubes or the cats can ingest the surgical scrub after surgery by grooming. One important variable between different clinics is how much surgical scrub is left on the hair and skin versus being completely rinsed off.

There has also been discussion regarding the difference between 4% chlorhexidinegluconate versus 2% chlorhexidine acetate. If the reaction is to chlorhexidine, then differences in concentration could certainly be a factor in expression of the syndrome. However, other chemicals are present in the scrubs (surfactants, perfumes, etc) and there has been no published data verifying the precise chemical cause of the reaction. The solution seems simple: Avoid using chlorhexidine scrubs to clean cat endotracheal tubes and thoroughly rinse the product off when using on cats.

- David Zeman

-JiU Mosley

- PamLeslie-Steen

- edited by Stephen Hooser,DVM,PhD

Reference:

South Dakota Animal Disease Research and Diagnostic Lab, Brookings,SD and Lakeview Veterinary Clinic, Mitchell, SD. Proceedings 105th annual meeting, SD Vet MedAssoc, 8/96, pl23.