T81.521A Obstruction due to foreign body accidentally left in body following infusion or transfusion, initial encounter

Billable ICD-10-CM code, FY2026.

Built from T81.521 with 7th character A (initial encounter).

Applies from T81 Complications of procedures, not elsewhere classified

Excludes2 (not included here)

• complications following immunization (T88.0-T88.1)
• complications following infusion, transfusion and therapeutic injection (T80.-)
• complications of transplanted organs and tissue (T86.-)
• specified complications classified elsewhere, such as:
• complication of prosthetic devices, implants and grafts (T82-T85)
• dermatitis due to drugs and medicaments (L23.3, L24.4, L25.1, L27.0-L27.1)
• endosseous dental implant failure (M27.6-)
• floppy iris syndrome (IFIS) (intraoperative) H21.81
• intraoperative and postprocedural complications of specific body system (D78.-, E36.-, E89.-, G97.3-, G97.4, H59.3-, H59.-, H95.2-, H95.3, I97.4-, I97.5, J95, K91.-, L76.-, M96.-, N99.-)
• ostomy complications (J95.0-, K94.-, N99.5-)
• plateau iris syndrome (post-iridectomy) (postprocedural) H21.82
• poisoning and toxic effects of drugs and chemicals (T36-T65 with fifth or sixth character 1-4)

Use additional code

• code for adverse effect, if applicable, to identify drug (T36-T50 with fifth or sixth character 5)

7th character note

• The appropriate 7th character is to be added to each code from category T81

7th character required

• A — initial encounter
• D — subsequent encounter
• S — sequela

Code annotations containing back-references to T81.521A

Back-references to T81.5

• Type 2 Excludes: T81.6 Acute reaction to foreign substance accidentally left during a procedure ("complications of foreign body accidentally left in body cavity or operation wound following procedure (T81.5-)")
• Type 1 Excludes: Z18 Retained foreign body fragments ("foreign body accidentally left during a procedure (T81.5-)")

Back-references to T81

• Code First: J98.51 Mediastinitis ("underlying condition, if applicable, such as postoperative mediastinitis (T81.-)")
• Type 2 Excludes: T78 Adverse effects, not elsewhere classified ("complications of surgical and medical care NEC (T80-T88)")
• Type 2 Excludes: T79 Certain early complications of trauma, not elsewhere classified ("complications occurring during or following medical procedures (T80-T88)")
• Type 2 Excludes: T79 Certain early complications of trauma, not elsewhere classified ("complications of surgical and medical care NEC (T80-T88)")
• Type 2 Excludes: T88 Other complications of surgical and medical care, not elsewhere classified ("complication following procedure NEC (T81.-)")

Diagnosis Index entries for T81.521A

• Foreign body › accidentally left following a procedure › infusion › resulting in › obstruction
• Foreign body › accidentally left following a procedure › transfusion › resulting in › obstruction

Nearby codes

• T81.520 Obstruction due to foreign body accidentally left in body following surgical operation
• T81.520A Obstruction due to foreign body accidentally left in body following surgical operation, initial encounter
• T81.520D Obstruction due to foreign body accidentally left in body following surgical operation, subsequent encounter
• T81.520S Obstruction due to foreign body accidentally left in body following surgical operation, sequela
• T81.521 Obstruction due to foreign body accidentally left in body following infusion or transfusion
• T81.521A Obstruction due to foreign body accidentally left in body following infusion or transfusion, initial encounter (this code)
• T81.521D Obstruction due to foreign body accidentally left in body following infusion or transfusion, subsequent encounter
• T81.521S Obstruction due to foreign body accidentally left in body following infusion or transfusion, sequela
• T81.522 Obstruction due to foreign body accidentally left in body following kidney dialysis
• T81.522A Obstruction due to foreign body accidentally left in body following kidney dialysis, initial encounter
• T81.522D Obstruction due to foreign body accidentally left in body following kidney dialysis, subsequent encounter