Page 53 - NNS 2014 Program & Abstract Book

various brain pathological conditions correctly. Therefore, we take a
closer look at the waveform of ICP in the several pathologic condi-
tion. The data of ICP waveform (ICPWF) was monitored in water
intoxicated rat model and continuous infusion model using Biopac
MP150 system (BIOPAC USAW). On cite of clinical, the ICP data of
16 trauma patients and 9 cerebrovascular disease patients in whom
ICPWF was monitored continuously by ICP express (Codman USA).
Differential ICPWF was calculated using LabChart Software (AD
instrument, USA).
Continuous monitoring of ICPWF showed clarify waveform change
and the change over time of the pressure. Single ICPWF was ex-
pressed as 3-phase wave (P1, P2, P3), 3-phase wave was reflected as
U1, U2, U3 in the differential ICPWF. In accordance with increased
ICP Continuous infusion as interstitial edema model demonstrates
high amplitude ICPWF and elevated P1, U1. In contrast, water in-
toxication as cellular edema model showed low amplitude ICPWF,
numerous b wave and U2 elevation during high ICP. Also in clinical
cases, ICPWF were divided roughly into two groups. One group
showed the increased U1, there was a tendency to include increased
ICP patients with a massive hematoma. Another elevated U2 group
tended to be more common in cases of severe traumatic brain injury
and cerebral infarction patients.
Although mean ICP was the same degree, the difference of ICPWFs
was observed in different pathogenic brain condition: extracellular
edema and intracellular edema. It suggests ICP waveform analysis
will be more valuable for assessment of brain’s pathological condition
like several type of brain edema.
Key words
differentiated intracranial pressure waveform
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FACTORS ASSOCIATED WITH CLINICIAN ADHERENCE
TO PEDIATRIC TRAUMATIC BRAIN INJURY GUIDELINES:
A QUALITATIVE STUDY
Brolliar, S.M.1, Vavilala, M.S.1, Whiteside, L.K.1, Thompson, H.J.1,
Mink, R.B.2, Wainwright, M.S.3, Groner, J.I.4, Bell, M.J.5, Giza, C.C.6,
Zatzick, D.F.1, Ellenbogen, R.G.1, Boyle, L.N.1, Mitchell, P.H.1,
Rivara, F.P.1
1University of Washington, Seattle, USA
2Harbor - UCLA and Los Angeles BioMedical Research Institute, Los
Angeles, USA
3Ann & Robert H. Lurie Children’s Hospital of Chicago, Chicago,
USA
4Ohio State University College of Medicine, Columbus, USA
5University of Pittsburgh, Pittsburgh, USA
6Mattel Children’s Hospital, UCLA, Los Angeles, USA
Evidence-based medicine may be influenced by provider beliefs and
competencies, professional norms, and managerial support. This study
assessed factors specific to adherence to the Brain Trauma Foundation
pediatric traumatic brain injury (TBI) guidelines. We conducted
nineteen focus groups with physicians (n = 54) and nurses (n = 74) who
treat pediatric patients with TBI at six pediatric-trauma centers
(Chicago, Columbus, Los Angeles, Pittsburgh, and Seattle). Sessions
were transcribed and examined using content analysis to identify
themes related to guideline adherence. Barriers and facilitators of
clinical adherence to the pediatric TBI guidelines were identified.
Three domains emerged: 1) the implementation and agreement of in-
stitutional protocols with the guidelines, 2) inter- and intra-department
communication and decision making, and 3) and perceived guideline
credibility and practicality. Dissemination and accountability struc-
tures used to implement institutional protocols, and the level of
agreement between protocols and TBI guidelines influenced clinical
decisions. Communication and decision making were affected by the
quality of platforms for inter- and intra-department communication
and the establishment of common treatment goals. Clinicians reported
value in clear care pathways, identified and accessible decision
makers, departmental liaisons, and provider consensus of guideline
application in local practice. Guideline credibility was rooted in the
perceived strength of the evidence, and alignment with clinical ex-
perience and training. Practicality was determined by applicability to
the patient. Identifying remediable provider and organizational fac-
tors that impact guideline adherence will inform changes to pediatric
TBI care pathways and the development of future TBI treatment
recommendations.
Key words
adherence, guidelines, qualitative, TBI
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COMPARATIVE STUDY OF OUTCOME MEASURES AND
ANALYSIS METHODS FOR TRAUMATIC BRAIN INJURY
TRIALS
Alali, A.S.1, Vavrek, D.3, Barber, J.2 , Dikmen, S.2 , Temkin, N.2
1University of Toronto, Toronto, Canada
2University of Washington, Seattle, United States
3University of Western States, Portland, United States
Batteries of functional and cognitive measures have been proposed as
alternatives to the Extended Glasgow Outcome Scale (GOSE) as the
primary outcome for traumatic brain injury (TBI) trials. We conducted
a study to compare GOSE and a battery of functional and cognitive
measures.
Several analytic methods were evaluated for each outcome. Using data
from a randomized trial, we simulated multiple treatment effects (0, 5,
7.5, and 10 percentage point improvement in favorable outcome on
GOSE and a corresponding deficit reduction for other measures) across
multiple outcome measures. Patients with complete data (n = 331) were
sampled with replacement (bootstrapping) to generate 10,000 samples for
each treatment effect (n = 400 patients/group). We calculated the per-
centage of samples where the null hypothesis was rejected to estimate the
power for each outcome with a suite of analytic techniques. Type-I error
was estimated by analyzing the simulation with 0% treatment effect.
All analytic techniques had appropriate rates of Type-I error
( £ 5%). Accounting for baseline prognosis, either by using sliding
dichotomy for GOSE or using regression-based methods substantially
increased the power over the corresponding analysis without ac-
counting for prognosis. The highest power was obtained using mul-
tivariate proportional odds regression to analyze GOSE or using
regression-based adjusted analysis of the battery of functional and
cognitive measures, assuming equal treatment effect across all com-
ponents. Analyzing GOSE using the fixed dichotomy provided the
lowest power for both unadjusted and regression-adjusted analyses.
Our findings are limited to situations where the assumption of equal
treatment effect across all measures is satisfied. This may not be true
in an actual clinical trial.
Accounting for baseline prognosis is critical to attaining high power
in phase-III TBI trials. The choice of primary outcome for future trials
should be guided by the domain of brain function an intervention is
likely to impact and the feasibility of data collection.
Key words
clinical trial, Glasgow Outcome Scale, outcome measures, research
design, statistical data analysis, traumatic brain injury
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