Thank you Dr. Sanaei-Zadeh for the letter and we welcome the opportunity to clarify few points as below.
Smoke inhalation is a common cause of Cyanide poisoning during fires, resulting in injury and even death. The diagnosis of cyanide poisoning remains very difficult and requires high index of suspicion based on history and clinical presentation [1]. In our case [2] cyanide poisoning does not fit the complete picture of cyanide poisoning, in which the victim will have a bitter, almond odor [3], which was not noticed in our patient.
Severe metabolic acidosis with high anion gap is expected in cyanide poisoning. Elevated serum lactate above 8 mmol/l following smoke inhalation is strongly suggestive of cyanide poisoning [4,5,1].
In our case the AGB was pH: 7.35, Pco2: 42, Hco3: 23, COHgb: 8.7%
Lactic acid was 1.47, Sodium: 140, Chloride: 108
For the above mentioned facts and absence of major clues, cyanide poisoning was not considered as provisional diagnosis and was not investigated.
Tobacco smoke is an important source of carbon monoxide. Carboxyhemoglobin(COHgb) commonly reaches a level of 10 percent in smokers and may exceed 15 percent as compared with 1–3% in nonsmokers [6]. This wide range (3–15%) depends on the amount of smoking, duration of smoking, lung functions, inhalers or non inhalers and other factors [7]. Therefore we believe that COHgb level of 8.7% in our case and responding to the treatment was reflecting a carbon monoxide poisoning.
Footnotes
Peer review under responsibility of King Saud University.
References
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