Carbon Monoxide Poisoning

FAQ (Frequently Asked Questions) and ANSWERS:

Question: Is it true that carbon monoxide is lighter than air, and will that property cause the CO to rise to the ceiling?
Answer: CO is usually a very minor component of any gas mixture, even one that is lethal to humans and animals. The simple fact is that the CO molecules CANNOT SEPARATE from the air molecules (oxygen, nitrogen, etc.). To do so would violate the Second Law of Thermodynamics. This does not occur, unless large amounts of energy are put into the system to cause it to happen. CO and the air that it is contained in will only rise if that volume of air is warmer than the surrounding air or is propelled there by a fan or pump.

Question: Will visiting to my family doctor help me in a case of CO poisoning?
Answer: The doctor can give you 100% oxygen to breathe, maybe hyperbaric oxygen ( HBO) - that will help. However, most of the tests used by physicians (blood counts, chest X-rays, body temperature, ECG, etc.) are useless in making a diagnosis, except in very severe CO poisoning. For the test for carboxyhemoglobin (COHb) to be useful/accurate, it must be done within 2-4 hours of leaving the site of CO exposure. Neuropsychological testing will show where most of damage is, if indeed, there is damage.

Question: Can you refer me to a doctor?
Answer: One of the most frequently asked questions is: "can you give me the name of a physician in my area who is knowledgeable about CO poisoning?" Unfortunately, I do not keep a database on thousands of physicians, even in the United States. The other problem with this question is that most physicians know little about CO poisoning - this is even more true for chronic CO poisoning. If you wish to have your symptoms treated (headache, dizziness, muscle/joint pain, depression, etc.) your physician SHOULD NOT have to be an expert on CO poisoning to do this. He/she can simply treat the symptom(s) by prescribing the appropriate medication (analgesic, anti-vertigo med., anti-depressant, etc.) to alleviate your suffering. Does this make sense? It is my approach to refer patients for the proper specialized evaluation following CO poisoning. This usually involves having them see a competent neuropsychologist (a Ph.D. person like myself), one experienced in the effects of CO.

Question: Is going to a physician the best way to get a health condition resulting from CO poisoning diagnosed?
Answer: This question is closely related to the one above. Generally, physicians are very reluctant to make a diagnosis of CO poisoning, due to their lack of training and experience in the area. Finally, as I comment on below, visiting many physicians to obtain a diagnosis of "CO poisoning" is not usually wise if you are seeking compensation in the courts. Most physicians will come up with an alternative, to them, more likely diagnosis (high blood pressure, psychiatric problem, pulled muscle, etc., etc.), that will be, to say the very least, unhelpful in a court battle. Neurologists are often consulted in CO cases. Unfortunately, few have any training in toxicology. Moreover, the "Gross Neurologic Exam" that they use does not have the power to ferret out the residual effects of CO poisoning or to objectively quantify them. If you need that physician's records for your court case, what he/she says could help you, or more likely, hurt your case. That is where an expert in CO poisoning is called in to analyze the situation and render an educated explanation of cause and effect for the health damage that has occurred.

Question: After a bout of CO poisoning can you tell me whether I will have lasting health damage?
Answer: No! We know of no markers or symptoms that accurately predict whether a person will have a complete recovery or will incur some lasting health damage. However, injury does increase with more severe CO poisoning and/or with longer duration of CO exposure.

Question: Should I go out and be evaluated for my cognitive/memory symptoms following CO poisoning by my local neuropsychologist?
Answer: If you have serious coronary artery disease, chest pain, etc. and need coronary artery bypass ("open-heart") surgery, would you go to a surgeon who does only 6 such operations a year? You would go to a surgeon who does 200, or 400, or more such operations per year. Experience and practice make all the difference. I can refer you to neuropsychologists with the most experience with CO poisoning.

Question: Can I have any Neuropsychologist do an evaluation following CO Poisoning?
Answer: I am frequently asked for the name/phone of a neuropsychologist in the victims' vicinity." There are two parts to this answer. First I do not make referrals to neuropsychologists until I have a good understanding of a case, that usually involves reviewing the CO Questionnaire and Adult History Questionnaire, and some of the relevant medical records. I usually am in a position to make referrals after I have officially become part of the case, ie. I have been retained by the victim(s) and/or legal counsel. Second, most neuropsychologists do not have an adequate understanding of what damage CO does, particularly chronic CO poisoning. Without this understanding, he/she may give incorrect tests, or may not know how to properly interpret the results of the tests given. Exercising my responsibility, I only refer to Neuropsychologists who have experience and competence in this emerging area of neuropsychological practice. Recently, I have begun assisting local neuropsychologists to do the very best testing possible, and to correctly interpret what the tests mean in terms of the damage that can result from CO poisoning.

Question: How long will the effects of CO last? - This is another very frequently asked question. Doc, "how long will it be until I recover to my healthy pre-CO-exposure state?"
Answer: Recovery time from CO poisoning is extremely difficult to predict, at best it is usually very slow, and recovery is often minimal/partial. I have spoken with people who continue to have debilitating symptoms from CO poisoning 10 and 15 years after the incident. The major portion of the recovery that occurs takes place during the first 9-12 months after termination of CO exposure. If you were actually able to choose your brain trauma, stroke or concussion in a motor vehicle accident is probably better than CO in terms of longterm recovery and outcome! The brain is usually better able in time to "wire-around" localized lesions produced by stroke and concussion than it is the diffuse damage that CO produces.

Question: Will the use of 100% oxygen at normal pressure (normobaric oxygen = NBO) or use of 100% oxygen at increased pressure (hyperbaric oxygen = HBO) eliminate the residual health effects caused by previous CO poisoning?
Answer: It may, or it may not. As an expert in this field, I neither recommend nor discourage the use of NBO or HBO for people who already have residual health effects as the result of CO poisoning. Most often a person feels better immediately following oxygen treatment, but then usually returns to his or her original (injured) state within a short period of time. If the costs of these treatments are not too high, you may wish to try, but be aware there are no guarantees connected with them. Currently there is no cure for CO-induced residual health damage.

Question: Are you a Toxicologist? - One of the most frequently asked questions is: "Are you a Toxicologist?"
Answer: I am not a "general" Toxicologist in the usual sense of the word. The dictionary defines TOXICOLOGIST as: "One who studies the nature, effects, and detection of poisons and the treatment of poisoning". or, "An individual who specializes in what is known regarding poisons; the scientific study of poisons, their actions, their detection, and the treatment of the conditions produced by them". My own definition is that a 'General Toxicologist' is someone who knows a little about a very large number of (poisonous) substances. I am just the opposite, I know a whole lot about Carbon Monoxide, but make no claim to know much about hundreds of other poisons! Thus, I am a toxicologist, and more than that, a highly specialized Toxicologist, an expert on the poison Carbon Monoxide.

.......... last changed 05/12/03

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