Chapter 18 includes symptoms, signs, abnormal results of clinical or other investigative procedures, and ill-defined conditions regarding which no diagnosis classifiable elsewhere is recorded. Signs and symptoms that point to a specific diagnosis have been assigned to a category in other chapters of the classification.
a. Use of symptom codes
Codes that describe symptoms and signs are acceptable for reporting purposes when a related definitive diagnosis has not been established (confirmed) by the provider.
b. Use of a symptom code with a definitive diagnosis code
Codes for signs and symptoms may be reported in addition to a related definitive diagnosis when the sign or symptom is not routinely associated with that diagnosis, such as the various signs and symptoms associated with complex syndromes. The definitive diagnosis code should be sequenced before the symptom code. Signs or symptoms that are associated routinely with a disease process should not be assigned as additional codes, unless otherwise instructed by the classification.
c. Combination codes that include symptoms
ICD-10-CM contains a number of combination codes that identify both the definitive diagnosis and common symptoms of that diagnosis. When using one of these combination codes, an additional code should not be assigned for the symptom.
d. Repeated falls
Code R29.6, Repeated falls, is for use for encounters when a patient has recently fallen and the reason for the fall is being investigated. Code Z91.81, History of falling, is for use when a patient has fallen in the past and is at risk for future falls. When appropriate, both codes R29.6 and Z91.81 may be assigned together.
e. Coma scale
The coma scale codes (R40.2-) can be used in conjunction with traumatic brain injury codes, acute cerebrovascular disease or sequelae of cerebrovascular disease codes. These codes are primarily for use by trauma registries, but they may be used in any setting where this information is collected. The coma scale may also be used to assess the status of the central nervous system for other non-trauma conditions, such as monitoring patients in the intensive care unit regardless of medical condition. The coma scale codes should be sequenced after the diagnosis code(s). These codes, one from each subcategory, are needed to complete the scale. The 7th character indicates when the scale was recorded. The 7th character should match for all three codes. At a minimum, report the initial score documented on presentation at your facility. This may be a score from the emergency medicine technician (EMT) or in the emergency department. If desired, a facility may choose to capture multiple coma scale scores. Assign code R40.24, Glasgow coma scale, total score, when only the total score is documented in the medical record and not the individual score(s).
f. Functional quadriplegia
Functional quadriplegia (code R53.2) is the lack of ability to use one's limbs or to ambulate due to extreme debility. It is not associated with neurologic deficit or injury, and code R53.2 should not be used for cases of neurologic quadriplegia. It should only be assigned if functional quadriplegia is specifically documented in the medical record.
g. SIRS due to Non-Infectious Process
The systemic inflammatory response syndrome (SIRS) can develop as a result of certain non-infectious disease processes, such as trauma, malignant neoplasm, or pancreatitis. When SIRS is documented with a noninfectious condition, and no subsequent infection is documented, the code for the underlying condition, such as an injury, should be assigned, followed by code R65.10, Systemic inflammatory response syndrome (SIRS) of non-infectious origin without acute organ dysfunction, or code R65.11, Systemic inflammatory response syndrome (SIRS) of non-infectious origin with acute organ dysfunction. If an associated acute organ dysfunction is documented, the appropriate code(s) for the specific type of organ dysfunction(s) should be assigned in addition to code R65.11. If acute organ dysfunction is documented, but it cannot be determined if the acute organ dysfunction is associated with SIRS or due to another condition (e.g., directly due to the trauma), the provider should be queried.
h. Death NOS
Code R99, Ill-defined and unknown cause of mortality, is only for use in the very limited circumstance when a patient who has already died is brought into an emergency department or other healthcare facility and is pronounced dead upon arrival. It does not represent the discharge disposition of death.
i. NIHSS Stroke Scale
The NIH stroke scale (NIHSS) codes (R29.7- -) can be used in conjunction with acute stroke codes (I63) to identify the patient's neurological status and the severity of the stroke. The stroke scale codes should be sequenced after the acute stroke diagnosis code(s). At a minimum, report the initial score documented. If desired, a facility may choose to capture multiple stroke scale scores. See Section I.B.14. for information concerning the medical record documentation that may be used for assignment of the NIHSS codes.