Unknown substance: When do you shut down?

When a patient presents at your ED with exposure to a potentially hazardous, but unknown substance, under what conditions do you shut down or limit operations? And what can you do to minimize your department’s downtime?

Emergency medicine observers agree that the last thing you want to do is shut down your ED, says Christopher Cannon, FACHE, system director at the office of emergency preparedness for Yale New Haven (CT) Health System.

"You have to be extremely careful about when and how you make that decision," he advises. "One of the main reasons for shutting down an ED clearly is that there are other patients or employees at risk — the potential for cross-contamination. That really is the overarching worry of the ED director: Am I going to contaminate the ED and the hospital, which is going to create an even greater risk to taking care of patients, and to the employees?"

The first step is to isolate and decontaminate the patient. "That’s critical," Cannon explains. In the case of an unknown substance, he says, a chemical is a little easier to identify than a biological agent, for example.

"The hospital may have some way of doing chemical detection," he offers. "There are strips out there now on the market, and some EMS and hazmat teams have them, and hospitals need to look into them." (Manufacturers of these strips include Safety Solutions, Boynton Beach, FL; and Smiths Detection, Warren, NJ, manufactures a chemical detection device.)

An excellent source for help in identifying unknown chemicals is the nearest poison control center, adds Kathy J. Rinnert, MD, MPH, assistant professor in the division of emergency medicine at the University of Texas Southwestern Medical Center in Dallas.

"They are absolutely phenomenal for telling you which labs can do assays for chemicals," she notes. The poison control center plays a critical intermediary role when an exposure has taken place in a public setting. The poison center will be providing resource information to the on-scene hazmat teams, to the local media, to the general medical community, and likely will also be able to coordinate communications between the different hospitals treating patients.

The centers, Rinnert explains, have pre-emptive partnerships with resources that can do testing on a 24/7 basis, "and they need to be able to guarantee expedited turnaround time when you have potential exposures," she says.

Another good source is the Chemical Transportation Emergency Center (CHEMTREC), a clearinghouse of information about hazardous materials, Rinnert says. (For contact information, see resources, below.) "You can type in a patient’s signs and symptoms, or the MSDS [the Material Safety Data Sheet, which appears on chemical containers] and it will spit you out all types of information — signs and symptoms, and if there is a low or moderate chance there has been exposure," she explains.

As long as the substance remains unknown, "you should be getting no EMS traffic — whether it’s critical care or not." Rinnert asserts. Ultimately, she adds, this level of diversion is the hospital’s decision, which they pass on to the EMS agencies. "You can only tell EMS you are on trauma divert; it’s still up to the medic to make the determination as to which is the next closest facility, and if they can, in fact, give credence to your request for divert," Rinnert says.

In terms of ensuring that you will reopen as quickly as possible, Cannon recommends taking the following steps:

  • Identify the substance as soon as possible; determine who has been affected.
  • If the ED is contaminated, follow appropriate procedures to decontaminate it.
  • Have the ability to shut down individual rooms, or portions of the facility.
  • Make sure that housekeeping, as well as your own clinical staff, know how to bag and isolate contaminated products.
  • In case of a terrorist attack, know your chain-of-custody issues as they pertain to working with law enforcement representatives.


For more information on diversion and reopening strategies, contact:

  • Christopher Cannon, FACHE, System Director, Office of Emergency Preparedness, Yale New Haven Health System, New Haven, CT. Phone: (203) 688-3224. E-mail: Christopher.Cannon@ynhh.org.

For more information on hazardous materials, contact:

  • Chemical Transportation Emergency Center (CHEMTREC). Phone: (800) 424-9300. Web: www.chemtrec.com.