Medical reference

Prehospital stroke scales.

Cincinnati screens. LAMS and RACE grade severity for CSC bypass. Here's the whole map.

Cincinnati Prehospital Stroke Scale (CPSS)

Three items. Any one abnormal = positive screen.

  • Facial droop — ask patient to smile / show teeth.
  • Arm drift — arms out, palms up, eyes closed for 10 sec.
  • Abnormal speech — repeat "You can't teach an old dog new tricks."

LAMS (Los Angeles Motor Scale)

0–5 severity from three motor items. LAMS ≥ 4 suggests LVO.

Item012
Facial droopAbsentPresent
Arm driftAbsentDrifts downFalls rapidly
Grip strengthNormalWeakNo grip

RACE (Rapid Arterial oCclusion Evaluation)

0–9 severity across 5 items. RACE ≥ 5 suggests LVO.

  • Facial palsy (0–2)
  • Arm motor (0–2)
  • Leg motor (0–2)
  • Head/gaze deviation (0–1)
  • Aphasia (left hemisphere) or agnosia (right) (0–2)

Field pearl

Document last known well, blood glucose, medications (especially anticoagulants), and time of scale — the receiving stroke team lives on those data points.

Stroke mimics

  • Hypoglycemia — always check a glucose.
  • Seizure with post-ictal Todd's paralysis.
  • Complex migraine.
  • Bell's palsy — spares the forehead.
  • Sepsis or severe electrolyte disturbance.

Frequently asked

Which stroke scale should EMS use?
Cincinnati (CPSS) is the fastest screen for any stroke. LAMS or RACE add severity — use them to decide whether to bypass a primary stroke center for a thrombectomy-capable comprehensive stroke center.
What is a positive Cincinnati scale?
Any one of: facial droop, arm drift, or abnormal speech. Sensitivity ~66% and specificity ~87% for stroke.
What LAMS score triggers CSC bypass?
LAMS ≥ 4 (0–5 scale) suggests large vessel occlusion (LVO) and thrombectomy candidacy. Many systems bypass with LAMS ≥ 4.
What RACE score suggests LVO?
RACE ≥ 5 (0–9 scale) has good sensitivity for LVO and is commonly used as the CSC bypass threshold.

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