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Objective Nociceptive Assessment in Ventilated ICU Patients: A Feasibility Study Using Pupillometry and the Nociceptive Flexion Reflex
Published on: July 4, 2018
Pupillary evaluation for differential diagnosis of coma
Y Tokuda1, N Nakazato, G H Stein
1Division of General Internal Medicine, Department of Medicine, Okinawa Chubu Hospital, Okinawa, Japan. tokuda_yasuharu@hosp.pref.okinawa.jp
Postgraduate Medical Journal
|February 5, 2003
Summary
Bedside pupil evaluation is useful for diagnosing coma causes. Pupil light reflex loss and anisocoria are key indicators of structural coma origins, aiding emergency room diagnosis.
Area of Science:
- Neurology
- Emergency Medicine
- Clinical Diagnostics
Background:
- Coma etiology determination is crucial for timely and effective treatment.
- Bedside clinical evaluation plays a vital role in emergency settings.
Purpose of the Study:
- To assess the utility of bedside pupil examination in identifying coma causes.
- To employ a probabilistic approach for etiological diagnosis of coma.
Main Methods:
- Prospective cohort study of 115 consecutive coma patients in an emergency room.
- Structured clinical examinations, laboratory tests, and imaging were performed.
- Etiology assignment based on predefined criteria by consensus.
Main Results:
- Coma etiology was identified in 98% of patients.
- Metabolic causes accounted for 60% and structural causes for 40%.
- Light reflex loss and anisocoria independently predicted structural coma origins.
Conclusions:
- Coma in emergency settings is frequently metabolic (60%) or structural (40%).
- Pupil examination findings, specifically light reflex loss and anisocoria, are significant predictors of structural etiology.
