Using the Pupillometer in Clinical Practice Claude Hemphill MD M.A.S. chmephill@sfgh.ucsf.edu Kathy Johnson RN, MSN KJOHNSON@queens.org Mary Kay Bader RN, MSN, CCNS Badermk@aol.com
Pupillometry: How It Works
NPi -100 Pupillometer Katherine Johnson, RN, MS, CNS-BC, CCRN, CNRN Neuro CNS Honolulu, Hawaii KJohnson@queens.org
Change of Shift: did the pupil really get bigger? Dark eyes: where is the iris/pupil boundary? Pin Point Pupils: any reaction? Are the pupils really fixed? Or did I see a reaction? Brisk? Or Sluggish to
THEN: NOW: Slide compliments of: Neurooptics NPi -100 Pupillometer
NPI (Neurological Pupillary Index) NPi is an algorithm developed by NeurOptics after many years of research in the modeling of pupil dynamics. INPUT Pupil variable NPi 1, 2, 3, n OUTPUT 5 3 Normal > 3-5 Abnormal < 3 0
Key Definitions
NPi Normal > 3-5 Abnormal < 3 MAX/MIN mm %CH % Constriction % or Percentage Change LAT Seconds Latency Constriction Velocity (CV) Maximum Constriction Velocity (MCV)
Conclusions The Npi -100 pupillometer can reliably detect smaller changes than the human eye and allows trending of gradual changes. Brisk, Sluggish or Non-reactive can be quantified Pupillometry does not replace the bedside Neuro Exam
Instructional Video
Bedside Nursing Use of Pupillometry
Indications Head Injury mild, moderate & severe Subarachnoid hemorrhage Intracerebral hemorrhage Ischemic stroke Craniotomy patients post-op Multisystem trauma patients with history of loss of consciousness Post Cardiac Arrest Patients
Considerations Medications Fentanyl affects pupillary reflex dilation Morphine affects pupillary size/constriction velocity (bolus dose) Symmetrical changes Midazolam can affect constriction velocity but it is symmetrical Paralytics no impact Propofol slows but symmetrical Barbiturates Makes them big and non-reactive
Application Data Forms
Data Form: Trending
Data Form: Trending
Mannitol IV Push ICP and Constriction Velocity ICP in mm Hg 35 30 25 20 15 10 5 0 Barb Coma Started Barbs off 1.6 1.4 1.2 1 0.8 0.6 0.4 0.2 0 C. Velocity Intracranial Pressure Constriction Velocity
Application: Case 1 41 year old female admitted as code stroke last night seen normal was 2300
Application: Case 1 ED to CT Taken to Neuro Interventional for possible Tx Pupillometer readings On arrival Right Left 4.5 mm 4.2mm -1.89-1.43 0300 4.5mm 4.2mm -1.89-1.43
Application: Case 1 Admitted to SICU at 0610 am Unable to open vessel with IA tpa 17 mg over 120 minutes and 2 passes of Merci Retrieval Pupillometer readings 0655 Small pupils hard to detect pupillary reaction constriction velocities of 0.15 and 0.23 with normal NPI 0943 constriction velocities of 0.05 and 0.07 and abnormal NPI (1.7 and 2.7) 1100 Right pupil 5.2 and Left 2.9
To CT and OR
Post Interventional Craniectomy ICP PbtO2 placed
Case 1: Pt Undergoes Hypothermia
Application in Clinical Setting 65 year old male Ischemic stroke transfer 4.5 hours after onset
Application: Case 2 To OR Post Craniectomy
Application: Case 2 Post op Decompressive Hemicraniectomy and Implementation of Hypothermia Normal NPI Post Decompressive Cranietomy
Application: Case 3 60 year old female Having dinner with husband Complains of sudden onset of severe headache Asks for her BP medicine Husband returns to table, wife is slumped in chair Calls 911 Admit as Code Stroke Hunt and Hess V Fisher IV To OR for ICP/PbtO2 Post coiling CT Increase blood
ICU Course Day 11-15 TCDs moderate spasm ICP d/c on Day 13 Pupil: RCv 1.2 ms LCv 1.1 ms Pupillometer readings WNL Day 15 PbtO2 dips Pupillometer slows R Cv 0.5ms and L Cv 0.0 ms Stat CT scan shows hydrocephalus New ICP ventriculostomy placed
ICU Course Day 15 Post ICP ICP 20s decreased to 6 Constriction velocities Increase to 2.55 (R) / 1.95 (L) Day 16 stable
Recovery Day 43 To Subacute facility Day 140 To Acute Rehab Day 170 Home
Application #4 Minor TBI TB, 18 year old male, fell from skateboard Arrival in ED GCS 4-4-3 Pupils Right 2.6 to 2.1 CV 1.1 mm/second Left 2.5 to 2.1 CV 0.98 mm/sec CT negative order to repeat CT in 4 hours Admitted to SICU Frequent Neuro Assess 3 hours later.gcs 2-4-2 Pupils Right 2.1 to 2.0 with CV 0.48 mm/sec Left 2.1 to 1.9 with CV 0.8 mm/sec Neurosurgeon called stat CT scan of brain reveals multiple contusions
Application #4 Minor TBI TB, 18 year old male, fell from skateboard CT shows contusions/shift of 8 mm To OR for ICP/Brain oxygen monitors Initial ICP 32 mm Hg opening pressure Mannitol intraop ICP decreases to 19 mm Hg Right CV 0.98 mm /sec Left CV 0.81 mm/sec
Application Case 5 TBI 21 year old male sustains severe TBI ICP/Brain oxygen monitors placed ICP controllable first 24 hours with ICP <20 Pupillometer Right Pupil 2.5 2.1mm CV 0.92 mm/sec Left Pupil 2.7 -- 2.3 mm CV 1.02 mm/sec Pupillometer slows 2 hours later
21 year old male sustains severe TBI ICP increases to 32 mm Hg 40 minutes later Treated with Hypertonic Saline ICP decreases Constriction Velocity returns to 0.95 mm/sec and 1.05 mm/sec
Conclusion Useful as an objective measurement between practitioners Trend data Incorporate overall clinical exam Early signal to investigate radiographic confirmation of neurologic deterioration
Clinical Research in Neurocritical Care Pupillometry
Pupillometer Taylor, Chen, Meltzer, et al J of Neurosurgery 98: 205-213 (Jan 2003) CV fell to 0.81 mm/sec when ICP trended to > 20
Temporal Progression of NPi : pupil diameter Patient B: TBI with an occipital parenchymal hemorrhage and a right lateral intraventricular hemorrhage. The CT scan revealed no cisterns and no midline shift and a mass size of 4cc (right). ICP raised above 50 mmhg few hours later accompanied by an increase of ICV. diameter 4-5 hr- 5 hour 4-7.5 hr- 7.5 hour abnormal NPi PLRi Abnormal 4-10.5 hrnon-reactive PLRi Abnormal NPi 10.5 hour 2 time 2 time 2 time red line = right pupil left line = left pupil
NPi and Subjects with abnormal/nonreacti ve NPi had a peak of ICP higher than subjects with normal NPi. The first occurrence of abnormal NPi relative to the time of the first peak of ICP was 15.9 hours. (CI=-28.56,-3) ICP
NPi and ICP
Reference Meeker, 2005 NPi -100 Pupillometer Instruction manual, May 2009 Neuroptics University