In simple words: The patient received too little of a general anesthetic during their first visit.

Underdosing of unspecified general anesthetics, initial encounter. This code is used when a patient experiences an adverse effect due to an insufficient dose of a general anesthetic during the initial encounter.

Example 1: A patient undergoing a surgical procedure receives an insufficient dose of general anesthetic, resulting in inadequate anesthesia and awareness during the procedure. This is the initial encounter for this underdosing event., A patient receiving general anesthesia for a medical procedure experiences inadequate sedation due to underdosing during the initial encounter, requiring additional medication to achieve the desired level of anesthesia., A patient in the emergency room requires general anesthesia for a painful procedure. Due to an error in calculation or administration, the patient receives an insufficient dose, experiencing discomfort and inadequate sedation during the initial encounter.

Documentation should clearly indicate the type of general anesthetic administered, the dosage given, the inadequate response to the anesthetic, and any corrective actions taken. The documentation should specify that this is the initial encounter related to underdosing and describe how it affected the procedure or treatment.

** For adverse effects of drugs, code first the nature of the adverse effect. The drug causing the adverse effect can be identified using codes T36-T50 with the fifth or sixth character as '5'. Additional codes can be used to specify manifestations of poisoning or underdosing (Y63.6, Y63.8-Y63.9, Z91.12-, Z91.13-). Excludes1: birth trauma (P10-P15), obstetric trauma (O70-O71), toxic reaction to local anesthesia in pregnancy (O29.3-), abuse and dependence of psychoactive substances (F10-F19), abuse of non-dependence-producing substances (F55.-), immunodeficiency due to drugs (D84.821), drug reaction and poisoning affecting newborn (P00-P96), and pathological drug intoxication (F10-F19).