Toxic effect of hydrogen cyanide, assault, sequela

This code describes the long-term or residual health problems resulting from a toxic exposure to hydrogen cyanide due to an intentional act of harm by another person. These sequelae can manifest as neurological deficits, cardiovascular issues, or other chronic conditions that persist after the initial acute poisoning. The assaultive nature indicates the poisoning was not accidental or self-inflicted.

Use this code when documenting a patient presenting with chronic health issues directly attributable to a past hydrogen cyanide poisoning that was determined to be an assault. This applies when the acute phase of the poisoning has resolved, and the patient is now being treated for the lasting effects. It is appropriate for follow-up visits addressing these persistent conditions.

• Always sequence this sequela code after the code(s) for the specific residual condition(s) being treated.
• Ensure documentation clearly links the current sequela to a past hydrogen cyanide poisoning and specifies the assaultive intent.
• Do not use this code for acute poisoning; instead, use the appropriate acute toxic effect code with the 7th character for initial encounter.