Y84.8

Other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

FY2027Chapter 20: External causes of morbidity/Y83–Y84 Surgical and other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure

BillableComplete code, valid to report

Y84.8 (also written Y848) is a billable ICD-10-CM diagnosis code for other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure. It is part of the FY2027 code set, effective October 1, 2026. It is one of the 10 codes in category Y84 (Other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure). Its coding notes include 1 Excludes1 entry and 1 Excludes2 entry.

Guidelines tip

From the FY2027 Official Guidelines. ICD10Ref adds no rules of its own.

An external cause code is never a principal or first-listed diagnosis. Its 7th character is assigned for each encounter and should match the injury or condition code.

Guidelines I.C.20.a.2; I.C.20.a.6External cause codesRead the official text

Excludes1

Not coded here. The listed conditions generally should not be reported together.

Also from chapter/block level (1 note)
Inherited from Y83–Y84 Surgical and other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure
  • misadventures to patients during surgical and medical care, classifiable to (Y62-Y69)

Excludes2

Not included here. Both codes may be reported if the patient has both conditions.

Also from chapter/block level (1 note)
Inherited from Y83–Y84 Surgical and other medical procedures as the cause of abnormal reaction of the patient, or of later complication, without mention of misadventure at the time of the procedure
  • breakdown or malfunctioning of medical device (after implantation) (during procedure) (ongoing use) (Y70-Y82)

Notes

Also from chapter/block level (1 note)
Inherited from Chapter 20 External causes of morbidity
  • This chapter permits the classification of environmental events and circumstances as the cause of injury, and other adverse effects. Where a code from this section is applicable, it is intended that it shall be used secondary to a code from another chapter of the Classification indicating the nature of the condition. Most often, the condition will be classifiable to Chapter 19, Injury, poisoning and certain other consequences of external causes (S00-T88). Other conditions that may be stated to be due to external causes are classified in Chapters I to XVIII. For these conditions, codes from Chapter 20 should be used to provide additional information as to the cause of the condition.