NIHSS score 20

This code indicates a National Institutes of Health Stroke Scale (NIHSS) score of 20, reflecting a severe neurological deficit following an acute cerebrovascular event. The NIHSS is a standardized, systematic assessment tool used to quantify the severity of stroke based on various neurological functions. A score of 20 suggests significant impairment across multiple domains, such as consciousness, motor function, sensation, and language.

Assign this code when documentation explicitly states an NIHSS score of 20, typically assessed during the acute phase of an ischemic or hemorrhagic stroke. This score is crucial for guiding treatment decisions, predicting patient outcomes, and tracking neurological status changes. Ensure the medical record clearly documents the NIHSS assessment and the specific score obtained.

• Always verify the exact NIHSS score documented; do not estimate or round.
• This code should be sequenced after the primary diagnosis for the acute stroke (e.g., I63.x for ischemic stroke, I61.x for hemorrhagic stroke).
• Do not use this code if the NIHSS score is not explicitly documented as 20; other codes exist for different score ranges.