Spetzler and Martin Grading for AVM



AVM Grading System

Spetzler-Martin grading system

  • stratify morbidity risk in patients following complete microsurgical resection of brain AVM to help inform treatment decision
  • AVM size (largest diameter of nidus)
    • < 3 cm = 1 point
    • 3-6 cm = 2 points
    • > 6 cm = 3 points
  • deep venous drainage = 1 point
    • deep veins include internal cerebral veins, basal veins, precentral cerebellar vein
    • all veins in posterior fossa are deep except for cerebellar hemispheric veins that drain into straight sinus transverse sinus
  • AVM adjacent to eloquent brain areas = 1 point
    • eloquent indicates identifiable neurological function and disabling neurological deficit if injured
    • includes sensorimotor, language, and visual cortices; hypothalamus and thalamus; internal capsule, brainstem, cerebellar peduncles, and deep cerebellar nuclei
  • grade = sum of scores (total score range 1-5 points)
  • major postsurgery deficits (0% mortality)
    • hemiparesis
    • long-term increase in aphasia
    • homonymous hemianopsia
    • severe deficit (including presumed normal perfusion pressure breakthrough) with major aphasia and hemiparesis

Postsurgery Outcomes Stratified by SM Grade:


AVM Validation

AVM Notes AVM Eloquent AVM morbidity  AVM factors AVM 08 AVM 01 AVM 02 AVM 03 AVM 04 AVM 05 AVM 06 AVM 07



Postsurgery Outcomes Stratified by SM Grade:




Spetzler, Robert F., and Neil A. Martin. “A Proposed Grading System For Arteriovenous Malformations”. Journal of Neurosurgery 65.4 (1986): 476-483. Web.

KCentra Contents and Dosing

kcentra dose and contents



Kcentra: coumadin reversal in acute major bleeding or need for urgent surgery:  

  • Pretreatment INR: 2 to <4: Administer 25 units/kg; maximum dose: 2,500 units
  • Pretreatment INR: 4 to 6: Administer 35 units/kg; maximum dose: 3,500 units
  • Pretreatment INR: >6: Administer 50 units/kg; maximum dose: 5,000 units

*Dosage expressed in units of factor IX activity
*give concurrent vitamin K
*Repeat dosing is not recommended (has not been studied).



Life-threatening hemorrhage with DOACs: (off label)

Optimal dosing not established

European Heart Rhythm Association, 50 units/kg (+25 units/kg if clinically necessary) recommended based on limited evidence in healthy volunteers

ICH due to various antithrombotic agents (NCS/SCCM [Frontera 2016]):

  • apixaban, edoxaban, rivaroxaban:
    • 50 units/kg if ICH within 3 to 5 terminal half-lives of drug exposure or when liver failure co-exists.
  • argatroban, dabigatran [if idarucizumab unavailable], bivalirudin, desirudin:
    • 50 units/kg if administered within 3 to 5 half-lives prior and no renal failure or there is renal impairment leading to drug exposure beyond 3 to 5 half-lives



Advantages of fixed dose KCentra:

  1. eliminates need for dose calculation based on patient-specific variables
  2. earlier start of hemostasis – limits hematoma enlargement?
  3. easier administration, no complex tables, reduction of door-to-needle time
  4. ?better clinical outcome

Retrospective study from Netherlands – fixed dose 1000 IU fIX PCC, ffd by 500 IU if INR>1.5, used Cofact (Sanquin BV) which contains FII FVII FIX FX and PrC and PrS, no activated factors or heparin. CONCLUSION:  that fixed dose required further dose/s to achieve target INR.  Door-to-needle time shorter, but not significant.  ?clinical outcome unknown.

Bottom line:  For now, calculate dose based on weight and INR.







“Prothrombin complex concentrate, 4-factor, unactivated, from human plasma”. Uptodate.com. Accessed 13 Dec. 2016.

Kcentra product insert.

Abdoellakhan, Rahat Amadkhan et al. “Fixed Versus Variable Dosing Of Prothrombin Complex Concentrate In Vitamin K Antagonist-Related Intracranial Hemorrhage: A Retrospective Analysis”. Neurocritical Care 26.1 (2016): 64-69.

Full Outline of UnResponsivenes (FOUR) score

FOUR Score

Full Outline of UnResponsivenes (FOUR) score
E4 = eyelids open or opened, tracking, or blinking to command
E3 = eyelids open but not tracking
E2 = eyelids closed but open to loud voice
E1 = eyelids closed but open to pain
E0 = eyelids remain closed with pain

M4 = thumbs-up, fist, or peace sign
M3 = localizing to pain
M2 = flexion response to pain
M1 = extension response to pain
M0 = no response to pain or generalized myoclonus status

Brainstem reflexes:
B4 = pupil and corneal reflexes present
B3 = one pupil wide and fixed
B2 = pupil or corneal reflexes absent
B1 = pupil and corneal reflexes absent
B0 = absent pupil, corneal, and cough reflex

Respiration pattern:
R4 = not intubated, regular breathing pattern
R3 = not intubated, Cheyne-Stokes breathing pattern
R2 = not intubated, irregular breathing
R1 = breathes above ventilatory rate
R0 = breathes at ventilator rate or apnea


Kiwon Lee, NeuroICU Book.