ICD-10 FAQ

 

FAQ 1.  What is ICD-10-CM?

ICD-10-CM is the current diagnosis code set used in the United States, effective October 1, 2015.  You may also hear about ICD-10-PCS (Procedure Coding System), another code set used for inpatient hospital procedures.  ICD-10-PCS will be discussed in FAQ 9 below.  

The International Classification of Diseases (ICD) is the copyrighted official publication of the World Health Organization (WHO). The primary purpose of ICD is for epidemiological tracking of illness and injury. ICD has been used in the US since 1949 (ICD­-6). The US version of ICD is managed by the National Center for Healthcare Statistics (NCHS) of the CDC with additional oversight by the cooperating parties: Centers for Medicare and Medicaid Services (CMS), American Hospital Association (AHA), and American Health Information Management Association (AHIMA). ICD-10-CM is the HIPPA transaction code set for diagnosis coding. The ICD-10-CM Official Guidelines for Coding and Reporting provides the rules for using the code set.

FAQ 2.  How is ICD-10 organized?                                                                                   

The ICD-10-CM tabular divides Diseases and Injuries into 21 sections or chapters.  It also contains three index tables for conditions related to 1) Chemicals and Drugs, 2) External Causes of Injury, and 3) Neoplasms which can expedite finding codes for those issues.  Unlike ICD-9-CM, no chapter in ICD-10-CM is considered as supplementary. The table below lists the 21 sections for Diseases and Injuries:

Chapter	Alpha Numeric
1. Certain Infectious and Parasitic Diseases	A00-B99
2. Neoplasms	C00-D49
3. Blood and Blood-forming Organs	D50-D89
4. Endocrine, Nutritional and Metabolic Diseases	E00-E89
5. Mental, Behavioral, and Neurodevelopmental Disorders	F01-F99
6. Nervous System	G00-G99
7. Eye and Adnexa	H00-H59
8. Ear and Mastoid Process	H60-H95
9. Circulatory System	I00-I99
10. Respiratory System	J00-J99
11. Digestive System	K00-K95
12. Skin and Subcutaneous Tissue	L00-L99
13. Musculoskeletal System and Connective Tissue	M00-M99
14. Genitourinary System	N00-N99
15. Pregnancy, Childbirth and the Puerperium	O00-O9A
16. Certain Conditions Originating in the Perinatal Period	P00-P96
17. Congenital Malformations, Deformations and Chromosomal Abnormalities	Q00-Q99
18. Symptoms, Signs and Abnormal Clinical and Laboratory Findings	R00-R99
19. Injury, Poisoning and Certain Other Consequences of External Causes	S00-T88
20. External Causes of Morbidity	V00-Y99
21. Factors Influencing Health Status and Contact with Health Services	Z00-Z99

Injury codes S00-S99 are listed by anatomical location and type of injury.  The following table illustrates truncated codes by anatomical position and injury type:

	Superficial	Open Wound	Fracture	Dislocation/ Sprain	Nerve	Blood Vessel	Organ	Crush	Amputation	Other
Head	S00	S01	S02	S03	S04	S05	S06	S07	S08	S09
Neck	S10	S11	S12	S13	S14	S15	S16	S17	S18	S19
Thorax (front/back)	S20	S21	S22	S23	S24	S25	S26	S27	S28	S29
Lower Torso (front/back)	S30	S31	S32	S33	S34	S35	S36	S37	S38	S39
Shoulder & Upper Arm	S40	S41	S42	S43	S44	S45	S46	S47	S48	S49
Elbow & Forearm	S50	S51	S52	S53	S54	S55	S56	S57	S58	S59
Wrist & Hand	S60	S61	S62	S63	S64	S65	S66	S67	S68	S69
Hip & Thigh	S70	S71	S72	S73	S74	S75	S76	S77	S78	S79
Knee & Lower Leg	S80	S81	S82	S83	S84	S85	S86	S87	S88	S89
Ankle & Foot	S90	S91	S92	S93	S94	S95	S96	S97	S98	S99

Most codes related to orthopedic conditions, injuries, poisonings and certain other external causes require a 7^th character to indicate the phase of care (see FAQ 4).

FAQ 3: In ICD 10-CM, how would a common diagnosis such as “ACS” be coded.

An important principle of coding is to use the diagnosis which best describes your clinical impression and to be as specific as possible. For example, using a non-specific diagnosis of “chest pain” (which codes to R07.9 “chest pain, unspecified”) is much less specific then using “precordial pain” (R07.2) when using a symptom code. On the other hand, ICD-10 includes several specific diagnoses such as unstable angina, STEMI, and NSTEMI (I20-21 for initial cardiac insult) which should be used when applicable.  Acute coronary syndrome (ACS) codes at I24.9 (Acute ischemic heart disease, unspecified). Additional codes are available to indicate presence or absence of additional risk factors, e.g. patient smokes, is an ex-smoker, or never smoked.

FAQ 4: In ICD 10-CM, how would a traumatic fracture from a trampoline fall be coded?

Orthopedic codes represent about 25% of codes found in ICD-10. It is important to clearly specify where the fracture is located (e.g. ramus of right mandible), and laterality (e.g. right ilium). In the example of an ankle fracture, it is important to describe whether it was displaced or nondisplaced, and whether it was a fracture of the medial malleolus, lateral malleolus, bi-malleolar or tri-malleolar fracture of the right or left lower leg.  For example, a non-displaced right lateral malleolar fracture would be coded to S82.64XA. Additional codes that could be extracted from your documentation would specify if the fracture resulted from a fall (e.g. W17.89XA Other fall from one level to another, initial encounter), and even the location of the fall or activity (e.g. Y93.44 Activity, trampolining) when you provide these details in your ED note.

ICD-10 Guidelines provide that fractures not specified as displaced or non-displaced should be coded to displaced.  Fractures not specified as open or closed are coded to closed.  The ICD-10 codes for fractures use a 7^th character to indicate, among other things, initial versus subsequent encounters for fractures.  Initial encounter is used while the patient is receiving active treatment for the fracture.   Initial encounter may also be assigned when a patient is transferred to another facility (e.g. trauma center) for higher level of care during the period of active treatment. A subsequent visit code would be used if an x-ray was being obtained to check healing status of fracture or if there was only a cast change or removal.  Documentation for subsequent encounters should describe routine healing, delayed healing, malunion or nonunion of fractures.  The suffix “S” for sequela is appropriate for other late effect manifestations or complications of an injury, exclusive of delayed healing, malunion or nonunion of fractures.   

FAQ 5.  How are poisoning, adverse effect and under dosing codes sequenced?

Codes T36-T50 describe poisoning by, adverse effect of, and under dosing of drugs, medications, and biological substances.   These are combination codes which include both the substance that was taken as well as the intent (e.g. accidental, intentional self-harm, undetermined).  No additional external cause code is required for this code set.  A poisoning code (accidental, intentional self-harm, assault and undetermined intent) may be a primary code, with manifestations sequenced following the poisoning code.  For example, intentional overdose of benzodiazepine with intent to self-harm, resulting in respiratory failure with hypoxia would be sequenced as follows:

1. T42.4X2A (Poisoning by benzodiazepines, intentional self-harm, initial encounter)   
2.  J96.01 (Acute respiratory failure with hypoxia)   

For adverse effect of a drug that has been correctly prescribed and properly administered, assign code(s) which describe the nature of the adverse effect (manifestation), followed by the appropriate code from the T36-T50 code set.  For example, new onset urticaria due to Lisinopril would be sequenced as follows:

1.  L50.8 (Other urticaria)   
2. T46.4X5A (Adverse effect of angiotensin-converting-enzyme inhibitors, initial encounter)   

 

ICD-10-CM introduced a code set for under dosing of medications, which is defined as taking less of a medication than is prescribed by a provider or a manufacturer’s instruction.  Under dosing codes should never be assigned as principal or first-listed codes.  For example, intractable generalized epileptic seizure, prescribed Dilantin with lab phenytoin level 4 ug/ml would be coded:

 

1. G40.319 (Generalized idiopathic epilepsy and epileptic syndromes, intractable, without status epilepticus)   
2. T42.0X6A (Underdosing of hydantoin derivatives)   

 

Additional ICD-10-CM codes are available to describe under dosing intent as documented:

 

Z91.120	Patient’s intentional under dosing of medication regimen due to financial hardship
Z91.128	Patient’s intentional under dosing of medication regimen for other reason
Z91.130	Patient’s unintentional under dosing of medication regimen due to age-related disability
Z91.138	Patient’s unintentional under dosing of medication regimen for other reason

 

FAQ 6.  Will there be updates and revisions to ICD-10-CM?

The ICD-10 Coordination and Maintenance Committee (C&M) is a Federal interdepartmental committee comprised of representatives from the Centers for Medicare and Medicaid Services (CMS) (who are responsible for PCS codes) and the Centers for Disease Control and Prevention's (CDC) National Center for Health Statistics (NCHS) (who are responsible for CM codes).  Each agency is responsible for approving coding changes, developing errata, addenda and other modifications within their area of responsibility.  Requests for coding changes are submitted to the committee for discussion at either the Spring or Fall C&M meeting. Almost all ICD-10-CM code additions and changes come from medical specialty societies or health care related groups. A public comment period follows which helps guide the agencies whether to accept, deny or modify the code proposals.

The C&M Committee meeting held in September 2015 discussed ICD-10-CM revisions and updates including discussion topics for laterality of rectal and peri-rectal abscess, asthma control status, atrial fibrillation, clostridium difficile recurrence, contact with knives and other sharp objects, heart failure, and the addition of a new ICD-10-CM category X50 for Overexertion and strenuous or repetitive movements. The agenda for the March 2016 meeting contained topics including discussion of Zika virus, classifications of myocardial infarction, hepatic encephalopathy, Type 2 diabetes mellitus with ketoacidosis, TMJ, and post-operative seroma. 

Anticipated ICD-10-CM changes effective October 1, 2016 reflect 1943 new codes, 422 revised codes, and 304 deleted codes. There are an unusually large number of new codes and changes for FY 2017 because of a partial code freeze that has been in effect since October 1, 2011 (last full update). Except for codes to capture new diseases, new and revised codes could not be published until one year after ICD-10-CM was implemented. Some of the fiscal 2017 changes include:

I160	Hypertensive urgency
I16.1	Hypertensive emergency
I16.9	Hypertensive crisis, unspecified
I69.010	Attention and concentration deficit following nontraumatic subarachnoid hemorrhage
I69.110	Attention and concentration deficit following nontraumatic intracerebral hemorrhage
I69.210	Attention and concentration deficit following other nontraumatic intracranial hemorrhage
I69.310	Attention and concentration deficit following cerebral infarction
I69.311	Memory deficit following cerebral infarction
K58.1	Irritable bowel syndrome with constipation
M61.0	Mastitis without abscess
M61.1	Abscess of the breast and nipple
R31.21	Asymptomatic microscopic hematuria
R31.29	Other microscopic hematuria
R82.71	Bacteriuria
R93.421	Abnormal radiologic findings on diagnostic imaging of right kidney
R93.422	Abnormal radiologic findings on diagnostic imaging of left kidney
Z29.14	Encounter for prophylactic rabies immune globin
Z79.84	Long term (current) use of oral hypoglycemic drugs

 

A new ICD-10-CM code set is introduced for external cause due to overexertion and strenuous movement:

X500XXA	Overexertion from strenuous movement or load, initial encounter
X500XXD	Overexertion from strenuous movement or load, subsequent encounter
X500XXS	Overexertion from strenuous movement or load, sequela
X501XXA	Overexertion from prolonged static or awkward postures, initial encounter
X501XXD	Overexertion from prolonged static or awkward postures, subsequent encounter
X501XXS	Overexertion from prolonged static or awkward postures, sequela
X503XXA	Overexertion from repetitive movements, initial encounter
X503XXD	Overexertion from repetitive movements, subsequent encounter
X503XXS	Overexertion from repetitive movements, sequela
X509XXA	Other and unspecified overexertion or strenuous movements or postures, initial encounter
X509XXD	Other and unspecified overexertion or strenuous movements or postures, subsequent encounter
X509XXS	Other and unspecified overexertion or strenuous movements or postures, sequela

 

Additionally, 2017 ICD-10 codes for fractures of the face and skull are revised to indicate right and left laterality.   National Institutes of Health Stroke Scale (NIHSS) scores (1-42) are included in a new code set R29.701-R29.742.   Codes for complications of indwelling urinary catheters (e.g. mechanical breakdown, displacement, leakage) are revised to indicate initial, subsequent and sequela encounters.  External cause codes for sport utility vehicle collisions are deleted, and now reflected in “car” code sets for driver, passenger, etc.   

Sources: 

New 2017 ICD-10-CM code additions and revisions:

ftp://ftp.cdc.gov/pub/Health_Statistics/NCHS/Publications/ICD10CM/2017/NewICD10CMCodes_FY2017.txt

September 2015 C&M agenda: http://www.cdc.gov/nchs/data/icd/Topic_Packet_09_22_23_15.pdf

March 2016 C&M agenda:  http://www.cdc.gov/nchs/data/icd/topic_packet_03_18_2015.pdf     

 

Requests for code changes to ICD-10-CM can be made by individuals or directed to the Coding and Nomenclature Advisory Committee.   Comments on proposals from a Coordination and Maintenance Committee meeting or requests for new/modified codes should be directed to: National Center for Health Statistics, ICD-10-CM Coordination and Maintenance Committee, nchsicd10CM@cdc.gov,

 

FAQ 7. Are "unspecified" diagnosis codes permitted with ICD-10-CM?

 Yes, these types of codes are permitted when a more specific diagnosis is not available at the time of the encounter. For example, if the patient is diagnosed with a pneumonia but the physician is not able to determine additional detail then "Pneumonia, organism unspecified" (J18.9) is a permissible diagnosis. However, if the pneumonia was associated with aspiration of vomit (J69.0) or Avian influenza (J09.X1), then those specific codes would be used.

Specificity is of particular importance, for example, as to the location of an injury, abdominal, back or limb pain. A specific diagnosis should indicate if an injury was of the left/ right forearm or upper arm or 3^rd digit finger as opposed to non-specific term "arm" or "finger." Diagnoses that do not list laterality when applicable, e.g. left vs. right, are more likely to be denied. For example, listing the diagnosis as “ankle sprain” (S93.409 Sprain of unspecified ligament of unspecified ankle) is more likely to elicit prepayment review than “right ankle sprain” (S93.401 Sprain of unspecified ligament of right ankle). The EP may not be able to tell which specific ligament is involved (e.g. calcaneofibular vs. tibiofibular) but should be able to note which side is affected.

The ICD-10-CM Official Guidelines for Coding and Reporting says:

Signs/symptoms and "unspecified" codes have acceptable, even necessary, uses. While specific diagnosis codes should be reported when they are supported by the available medical record documentation and clinical knowledge of the patient's health condition, there are instances when signs/symptoms or unspecified codes are the best choices for accurately reflecting the healthcare encounter. Each healthcare encounter should be coded to the level of certainty known for that encounter.

If a definitive diagnosis has not been established by the end of the encounter, it is appropriate to report codes for sign(s) and/or symptom(s) in lieu of a definitive diagnosis. When sufficient clinical information isn't known or available about a particular health condition to assign a more specific code, it is acceptable to report the appropriate "unspecified" code (e.g., a diagnosis of pneumonia has been determined, but not the specific type). Unspecified codes should be reported when they are the codes that most accurately reflect what is known about the patient's condition at the time of that particular encounter. It would be inappropriate to select a specific code that is not supported by the medical record documentation or conduct medically unnecessary diagnostic testing in order to determine a more specific code. (Section I.B.18,underline added)

This information was also published in AHA Coding Clinic^® for ICD-10-CM/PCS, Second Quarter 2013, pages 29-30.

Payers may need to be reminded, "Adherence to these guidelines when assigning ICD-10-CM diagnosis and procedure codes is required under the Health Insurance Portability and Accountability Act (HIPAA)."  (ICD-10-CM Official Guidelines for Coding and Reporting) Additional coding guidance is published quarterly in AHA Coding Clinic^® for ICD-10-CM/PCS.

FAQ 8.  Are External Cause Codes required for ICD-10-CM?

There is no national requirement for mandatory ICD-10-CM external cause code reporting. Unless you are subject to a State-based external cause code reporting mandate or these codes are required by a particular payer, you are not required to report ICD-10-CM codes found in Chapter 20 of the ICD-10-CM, External Causes of Morbidity.  Check with your local payers to determine whether they require external cause codes. However, it is not unreasonable that this information would be part of the ED documentation and could be extracted by the hospital or other party as required.

FAQ 9.  What is ICD-10-PCS?

ICD-10-PCS (Procedure Coding System) is designed to replace Volume 3 of ICD-9-CM. As with ICD-9, ICD-10-PCS is ONLY used by hospitals to show inpatient resource utilization. It does not affect services provided in the outpatient setting, including the ED. It is not intended to show physician work, and CMS has stated ICD-10-PCS is not intended to replace CPT for physicians procedure coding.

CPT remains the procedure coding standard for physicians, regardless of whether the physician services were provided in the inpatient or outpatient setting. Any third party payer asking for ICD-10-PCS procedure codes to be submitted along with CPT codes for outpatient services is in violation of HIPAA regulations and subject to fines by CMS.

FAQ 10.  Where can I learn more about ICD-10-CM and ICD-10-PCS?

For the first few months of ICD-10 implementation, the ICD-10 Coordination Center (ICC) appointed an ombudsman (William Rogers MD) to respond to provider questions and concerns about ICD-10. The ICC is now closed and will no longer accept inquiries.

For requests to update the ICD-10-CM codes, please note The National Center for Healthcare Statistics of the CDC is responsible for the development and maintenance of ICD-10-CM. Please send your ICD-10-CM comments to:  National Center for Health Statistics, ICD-10-CM Coordination and Maintenance Committee, nchsicd10CM@cdc.gov

ICD-10-CM Official Guidelines:  http://www.cdc.gov/nchs/data/icd/10cmguidelines_2016_Final.pdf

 

2016 ICD-10-CM codes (indexes and tabular): http://www.cdc.gov/nchs/data/icd/icd10cm/2016/ICD10CM_FY2016_Full_PDF.ZIP

http://www.cdc.gov/nchs/data/icd/icd10cm/2016/ICD10CM_FY2016_Full_XML.ZIP

 

ICD-10 Fee-For-Service educational resources, including MLN Matters® articles, MLN products, MLN Connects® videos, and CMS resources: http://www.cms.gov/Medicare/Coding/ICD10/Medicare-Fee-for-Service-Provider-Resources.html on the CMS website

 

 

For questions about Claims Processing and Payment or Local Coverage Determinations:

Contact your Medicare Administrative Contractor (MAC) for guidance. You can find the list of MACs at this link: https://www.cms.gov/Medicare/Coding/ICD10/ICD-10-Provider-Contact-Table.pdf 

Additional resources are located on the ACEP website: 

ICD-10-CM and the Emergency Physician

ICD-10-CM For the Busy Emergency Physician

ICD-10-CM ED Clinical Examples

Disclaimer 

The American College of Emergency Physicians (ACEP) has developed the Reimbursement & Coding FAQs and Pearls for informational purposes only.   The FAQs and Pearls have been developed by sources knowledgeable in their fields, reviewed by a committee, and are intended to describe current coding practice. However, ACEP cannot guarantee that the information contained in the FAQs and Pearls is in every respect accurate, complete, or up to date. The FAQs and Pearls are provided "as is" without warranty of any kind, either express or implied, including but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Payment policies can vary from payer to payer. ACEP, its committee members, authors or editors assume no responsibility for, and expressly disclaim liability for, damages of any kind arising out of or relating to any use, non-use, interpretation of, or reliance on information contained or not contained in the FAQs and Pearls. In no event shall ACEP be liable for direct, indirect, special, incidental, or consequential damages arising out of the use of such information or material. Specific coding or payment related issues should be directed to the payer. For information about this FAQ/ Pearl, or to provide feedback, please contact David A. McKenzie, CAE, Reimbursement Director, ACEP at (972) 550-0911, Ext. 3233 or dmckenzie@acep.org 

 Updated 08/10/2016