eeg.newborn.classroom.pdf.99999999999999

eeg
newborn classroom

1. Continuous EEG Monitoring
in the Newborn
Robert White, MD

2. Learning Objectives
Upon completion of this session, you will be
able to: z
Discuss what current continuous EEG
monitors can and can't tell us
z
Review the possible uses (and misuses) of
this technology

3. Presentation Outline
z
What we know about continuous EEG
monitoring
z
A little bit about the technique itself
z
Exploring logic of aEEGuse for seizure
detection and monitoring of therapy
z
Suggestions for acquiring expertise
z
Resources

4. Continuous EEG Monitoring
in the Newborn -Why?
z
A real-time indicator of cerebral activity •
For diagnosis/prognosis following HIE
•
For seizure detection and monitoring
•
For developmental care
Why not?
•
Cost
•
Unconvinced of value/fear of misuse

5. aEEG–How is it derived?
z
Background + Transients
z
Filtered, rectified
z
Compressed -reams of paper in one screen

6. EEG
Courtesy T. Courtesy T. Weiler Weiler, Olympic Medical , Olympic Medical

7. Rectification

8. General Categories of aEEG
Activity
Burst-
Suppression
Discontinuous
Continuous
aEEG Raw EEG

9. Burst Suppression
Courtesy T. Courtesy T. Weiler Weiler, Olympic Medical , Olympic Medical

10. General Categories of aEEG
Activity -Continued
Seizures
Inactive
Continuous Low
Voltage
aEEG Raw EEG

11. aEEG –Typical tracings
z
CFM studies
have prognostic
significance post-
asphyxialinjury
z
Faster recovery
of CFM yields
better prognosis
at two years
z
Normal early
CFM, good
prognosis
Ter Horst HJ, et al. Ped Res 2004; 55:1025

12. EEG
Courtesy T. Courtesy T. Weiler Weiler, Olympic Medical , Olympic Medical

13. Moderately Abnormal

14. Seizure EEG
DeVries DeVriesL, L, Toet ToetM, Clin. Perinatol., 2006 M, Clin. Perinatol., 2006
Term infant with middle cerebral artery infarct Term infant with middle cerebral artery infarct

15. Premature infant seizures
25 wk. infant with Grade 4 IVH 25 wk. infant with Grade 4 IVH
DeVries DeVriesL, Clin. Perinatol., 2006 L, Clin. Perinatol., 2006

16. Seizures; Burst-suppression
and jet ventilator background

18. Immature aEEG
z
Less mature CFM
recordings were
characterized by
discontinuous
background activity,
with depressed
electrical amplitude
and wide bandwidth
(Burdjalov, et al)
26 weeks PCA 26 weeks PCA

19. z
With advancing age,
the CFM pattern
became increasingly
continuous, with
progressive elevation
of the minimum level of
electrical amplitude,
and narrowing of the
amplitude’s bandwidth
29 weeks PCA 29 weeks PCA

20. z
Cyclic 20 -30 minute
periods of wider
amplitude began to
emerge after the third
week of life, and
were recognizable by
30 -31 weeks post-
conceptional age in
the healthy pre-term
infant
31 weeks PCA 31 weeks PCA
30 weeks 30 weeks
PCAPCA

21. The effect of IVH on aEEG
z
In babies with grade
III and grade IV IVH,
discontinuity of the
tracing, and the
degree of electrical
amplitude
depression were
even more marked
than normal for
gestational age
31 weeks PCA, Grade 3 IVH 31 weeks PCA, Grade 3 IVH
31 weeks PCA, no IVH 31 weeks PCA, no IVH

22. z
In all patients with IVH,
there was delay in the
appearance of
maturational changes
and emergence of the
cyclic pattern of
cerebral activity, with
persisting discontinuity
compared to infants
without IVH of
comparable
developmental age.
34 weeks PCA, IVH 34 weeks PCA, IVH
33 weeks PCA, 33 weeks PCA,
IVHIVH

23. General Categories of aEEG
Activity
Rare or absent Near-silence
(1-3 uV)
Low-voltage background with little
or no spontaneous activity
Continuous Low
Voltage
None Artifact only No detectable cortical activity Inactive
High-voltage bursts
(25-100 uV)
Near-silence
(1-3 uV)
Mostly near-silence, with
occasional high-voltage bursts
Burst-Suppression
NA NA Rhythmic, stereotypical, high-
voltage spikes
Seizure
Significantly higher
than background
Low voltage
(2-5 uV)
Periods of activity interspersed
with quiet periods
Discontinuous
Modestly higher
than background
Modest voltage
(5-10 uV)
Always something going on, with
or without sleep-wake cycling
Continuous
Spontaneous
Activity
Background Brief description

24. How Can aEEGBe Used?
HIE Evaluation,
Treatment and
Prognosis

25. aEEGEnhances Diagnosis and
Prognosis Following HIE
z
Al Naqueeb et al (Pediatrics
1999)
•
56 cases of neonatal encephalopathy
•
21 infants with normal aEEG
•
19 were normal at 18-24 month
follow-up
•
35 infants with abnormal aEEG
•
27 died or had neurological
abnormalities

26. Diagnosis/Prognosis
Following HIE
z
Toetet al (Arch DisChild Neo Ed
1999)
•
33 infants normal or mildly abnormal aEEG
•
30 were normal at follow-up, 1 died, and
2 had global delay
•
35 infants burst-suppression or low voltage
•
22 died; 8 major handicaps; 5 normal

27. Diagnosis/Prognosis
Following HIE
z
Subsequent studies have shown that
combining aEEGwith clinical exam and
imaging provides earlier prognostic
information, with better sensitivity and
specificity, than exam and imaging alone.
z
aEEGis used as an entry criterion for
some therapeutic hypothermia protocols

28. How Can aEEGBe Used?
Seizure Detection
and Management

29. aEEGImproves Seizure
Detection/Monitoring
z
Majority of seizures (~70%) in neonates are
electrographic, without clinical correlates
z
Electrographic seizures are not more benign than
electroclinical seizures
z
Continuous recording detects/documents seizure
frequency better than observation + conventional
EEG alone
z
Anticonvulsant therapy can produce electro-clinical
dissociation, obscuring continued seizure activity

30. Seizure Detection/Monitoring
z
Continuous EEG is a supplement to
conventional EEG, not a substitute
z
No guidance yet on treatment

31. Neonatal Seizure Patterns
R. Clancy, Clin. Perinatol., 2006 R. Clancy, Clin. Perinatol., 2006

32. How Can aEEGBe Used?
Developmental Care

33. aEEGin Developmental Care
z
Allows identification of sleep/wake periods,
which might improve care practices and
provide an additional parameter in
research trials
z
Normal developmental progression of
aEEgby gestational age has been
described, which might assist in providing
age-appropriate care and in identifying
high-risk infants for follow-up

34. Indications for Continuous EEG
Limited Broad Developmental Care
Moderate Moderate Seizure
detection/monitoring
High Limited Diagnosis/prognosis
of HIE
Level of
supportive evidence
Potential breadth of application
Indication

35. Continuous EEG -
Technology
z
BrainZ –BRM2 •
Two channels, surface or needle electrodes
z
Day One –Neurotrac(FDA approval pending) •
Eight channels, surface electrodes
z
Olympic –CFM 6000 •
One channel, surface or needle electrodes
z
VIASYS –NicoletOne •
16 channels, surface electrodes

36. BrainZ BRM2 Monitor
z
Two-channel
recording allows
detection of some
asymmetries

38. Olympic CFM 6000
z
Single channel
z
Surface or needle
electrodes (less
prone to artifact)

39. Needle electrode placement
z
Can be covered
by a headband, if
desired

40. Putting what we know about
aEEGinto clinical context…..

41. Key Questions
z
Who should be monitored?
z
What seizures to treat?
z
Can additional diagnostic/prognostic info be
provided by aEEGin high-risk infants?
z
Appropriate training/documentation •
Without formal training/certification, the
potential for misadventure is considerable
z
Costs/charges/reimbursement

42. Proposed Indications for
Seizure Monitoring
z
5 minute Apgar <5, or other evidence for HIE
z
Clinical suspicion of seizures
z
Sarnatstage 2-3
z
High-risk infants during neuromuscular
blockade
z
Severe apnea
z
IVH/ICH
z
ELBW infants
z
Infants requiring ECMO or surgery for CHD

43. Possible Indications for
Treatment of Seizures
z
Status epilecticus
z
Repetitive, prolonged seizures in a
child, especially when clinical indicators
of seizure activity (e.g., severe apnea)
might be obscured or misinterpreted as
“normal”

44. Treatment of Repetitive Seizure
Activity Using aEEG
z
If any
seizures treated (94% of neonates with seizures in
2007 Barthasurvey), then aEEGprobably better than clinical
evaluation and conventional EEG alone.
z
If in a given situation you would treat seizures seen on
conventional EEG, it is logical to use same criteria when
seizures identified by aEEG, since clinical implications are
similar.
z
If you could get a reliable co nventional EEG at 0200 on a
ventilator + multiple other devices aEEGmight not be
needed, but since most of us can’t…..

45. Why Monitor?
The ABGsAnalogy
z
Continuous EEG is to conventional EEG as
SaO2 monitoring is to ABGs.
z
ABGs–more info, more accurately, but
SaO2 allows real-time monitoring, something
ABGscannot do.
z
Conventional EEG –more info, more precise
than aEEG, but continuous EEG allows real-
time monitoring, which conventional EEG
cannot provide.

46. Why Monitor?
The ABGsAnalogy
z
In a very stable baby, perhaps monitoring O2
sat for 30 minutes a day is enough, but in a
sick infant, it’s grossly inadequate
z
If a 30 minute EEG gave a representative
picture of the full 24 hour activity, one could
logically base therapy on the conventional
EEG, but we now know that it often doesn’t

47. Further Context
z
Use of aEEGhas not increased frequency of our
infants who go home on anticonvulsants (much
lower than the 75% found in the Barthasurvey)
z
Concerns about side-effects of phenobarbare
largely related to its long-term use
z
Everybody
intervenes with some seizures!
•
Example –seizure leading to severe apnea, requiring ventilatoryassistance
So, bottom line suggestion is to –
monitor aggressively, treat cautiously

48. More “Bottom Line”
z
Continuous EEG monitoring has the potential
to make our treatment of neonatal seizures
more informed and more rational
z
On the other hand, it also has the potential to
make our treatment of neonatal seizures
more irrational, more invasive, and more
expensive
So...monitor aggressively; treat cautiously

49. Proposed Training Sequence
z
Preliminary training •
Read the Atlas
and Clinics
•
Review key references
•
Attend pertinent conferences
•
Establish contact with mentor(s)
•
Attend in-service by manufacturer’s
representative

50. Proposed Training Sequence
z
Early clinical use •
Daily “EEG review”rounds
•
Review challenging tracings with
mentor(s)
•
Attend a formal training course

51. Proposed Training Sequence
z
Continuing Education •
Regular “journal club”
•
Competency checks
•
Conferences

52. The Future
z
More screening/diagnostic tools –e.g., NIRS,
multiple-array EEG and others?
z
New neuroprotective interventions may
require screening devices available 24/7.
z
Window into the neonatal brain is opening for
real-time evaluation of well-intended but not
always benign interventions –we need better
monitoring tools!

53. Resources
z
Dr. Whitelaw’s course: Cerebral Function Monitoring
and Neurophysiology for Neonatologists -
www.neonatalneurology.org.uk/neurophysPoster.htm
z
3rd International Conf. on Neonatal Brain Monitoring
and Neuroprotection, Feb 19-22, 2009, Disney World
www.cme.hsc.usf.edu/brain/
z
Hellstrom-Westas, deVries, Rosen. An Atlas of Amplitude-integrated EEGs in the Newborn (new edition due this year).
z
Brain Monitoring in the Neonate
Clinics in Perinatology
, Sept. 2006

54. Thank You!
Please feel free to reach me at: Please feel free to reach me at:
[email protected] [email protected]

55. Financial
z
Hospital billing code we use –95950 –
“Special EEG Tests”

56. z
Clinically
apparent
is not the same as
clinically
significant
•
But what is clinically significant
remains to be determined