CO causes lifetime damage: Utah expert and his patient wonder how many are in danger

Cynthia Smith was poisoned silently and slowly in her own home every day as she worked, ate, read and watched TV.

Even as she slept, the colorless, tasteless, odorless poison attacked her brain, snatching parts of its functioning for two and a half years before the stealthy culprit was discovered.

Her faulty furnace leaked carbon monoxide — not enough to kill her, but more than enough to damage her brain, her health, her emotions, her job and her future.

Today, the former venture capitalist and 30-something businesswoman from San Francisco is dealing with brain damage, heart trouble and the possibility of other health problems after she unknowingly inhaled the poison for months on end.

Smith is in Salt Lake City to visit Dr. Lindell Weaver, medical director of the Hyperbaric Medicine Center at Intermountain Medical Center, whose most recent study on carbon monoxide poisoning was published Wednesday in the New England Journal of Medicine. He is one member of a team of doctors now helping Smith deal with the consequences of the poisoning, which she discovered in the fall of 2001.

Both Weaver and his patient wonder how many others are now being poisoned little by little, with children, unborn babies and older people at particular risk for damage with exposure to CO levels that may not do the same harm — or even create symptoms — in healthy adults.

The study describes the potential for ongoing impact on those suffering from long-term exposure, and advises that such patients "should be informed that they may not fully recover after poisoning." Patients not only have been deprived of oxygen that is critical to brain function, but the inflammation caused by CO results in injury to tissue that may explain symptoms in patients that develop long-term cognitive problems, the study said.

Yet it was the initial lack of specificity and severity of her symptoms that kept Smith from discovering the problem, and getting the necessary treatment more quickly, she said.

"I had nausea, headaches and general fatigue based on the time of exposure or whether I was out of town. If you were to create a list, there could be 20 to 30 symptoms," none of which specifically pointed to CO poisoning, she said. Loss of balance and a lack of concentration were also present.