Q&A: Using the Glasgow Coma Scale
Q: Can you give us advice on coma documentation and coding? We do not use the Glasgow Coma Scale (GCS) at our organization.
A: My best advice related to coma is to use the GCS. If your nurses are not documenting these scores, they should do so, so you can capture this information. If the coding staff is not assigning these codes, they should.
You want to report the scale with the separate components (so the information should be placed within the medical record to allow for the separate components to be captured). Here’s the code category for the GCS scores. The bolded codes are classified as MCCs:
- R40.21, Coma scale, eyes open
- R40.211, Coma scale, eyes open, never
- R40.212, Coma scale, eyes open, to pain
- R40.213, Coma scale, eyes open, to sound
- R40.214, Coma scale, eyes open, spontaneous
- R40.22, Coma scale, best verbal response
- R40.221, Coma scale, best verbal response, none
- R40.222, Coma scale, best verbal response, incomprehensible words
- R40.223, Coma scale, best verbal response, inappropriate words
- R40.224, Coma scale, best verbal response, confused conversation
- R40.225, Coma scale, best verbal response, oriented
- R40.23, Coma scale, best motor response
- R40.231, Coma scale, best motor response, none
- R40.232, Coma scale, best motor response, extension
- R40.233, Coma scale, best motor response, abnormal
- R40.234, Coma scale, best motor response, flexion withdrawal
- R40.235, Coma scale, best motor response, localizes pain
- R40.236, Coma scale, best motor response, obeys commands
The codes that add MCCs would also affect your severity of illness and risk of mortality scores. I found physicians often hesitant to document coma, but we could capture the complexity of the patient by assigning these codes based off nursing documentation.
There are chapter specific guidelines about the use of these codes:
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).
Do not report codes for individual or total Glasgow coma scale scores for a patient with a medically induced coma or a sedated patient.
See Section I.B.14 for coma scale documentation by clinicians other than patient's provider.
Code R40.20 leads to unspecified coma, which also provides an MCC. Note the inclusion term of unconsciousness not otherwise specified (NOS)—if your provider is documenting unconsciousness, the R40.20 code can be assigned.
Here are a few helpful questions I suggest considering with the GCS:
- Does the patient’s documented diagnosis correlate with their coma score?
- Does “unresponsive” or “unarousable” equal coma?
- If the patient is in a coma, are we capturing any/all associated secondary diagnoses, such as cerebral edema, brain compression, or respiratory status?
If you have a low GCS and no documented co-morbidities or no documented condition that explains the low GCS, you likely have a query opportunity.
Editor’s Note: Laurie L. Prescott, RN, MSN, CCDS, CDIP, CRC, CDI education director at HCPro in Middleton, Massachusetts, answered this question. Contact her at email@example.com. For information regarding CDI Boot Camps, click here.