Upload
karahman
View
217
Download
0
Embed Size (px)
Citation preview
8/16/2019 ICP Waveform Analysis J Ball 2004
1/16
ICPICP
WaveformWaveform
Analysis Analysis
Joanne Ball RNJoanne Ball RN
Intensive Care UnitIntensive Care UnitWestmeadWestmead HospitalHospital
8/16/2019 ICP Waveform Analysis J Ball 2004
2/16
Why look at ICP waveformWhy look at ICP waveform
analysis?analysis?
“…provides information about intracranial dynamics that can help
identify individuals
who have decreased adaptive capacity and are
at risk for increases in ICP
and decreases in CPP,
which may contribute to secondary brain injuryand have a negative impact on neurologic outcome.”
C.J Kirkness et. al, 2000, 32;5, 271.
8/16/2019 ICP Waveform Analysis J Ball 2004
3/16
8/16/2019 ICP Waveform Analysis J Ball 2004
4/16
MonroMonro--Kellie doctrineKellie doctrine
increase in one component
(brain swelling)
or
addition of new component
(haematoma)
displaces another component
• skull – closed box, fixed volume
• contents
– blood, brain and CSF
– non-compressible fluids
8/16/2019 ICP Waveform Analysis J Ball 2004
5/16
ATLS Course Manual, American College of Surgeons, 1997
8/16/2019 ICP Waveform Analysis J Ball 2004
6/16
“compliance reflects theability of the intracranial
system to compensate for
increases in volumewithout subsequent
increases in ICP. When
compliance is decreased
even small increases in
intracranial volume
result in large increases
in ICP”
C.J Kirkness et. al, 2000, 32,5 271
8/16/2019 ICP Waveform Analysis J Ball 2004
7/16 ATLS Course Manual, American College of Surgeons, 1997
8/16/2019 ICP Waveform Analysis J Ball 2004
8/16
Methods of Methods of
ICP measurementICP measurementTechnology
• external strain gauge
• catheter tip (internal)
strain gauge
• fibre-opticLocation
• Ventricular (EVD/IVC)
• Intraparenchymal• Subarachnoid
• Subdural/Extradural
• External Fontanelle
8/16/2019 ICP Waveform Analysis J Ball 2004
9/16
Normal ICPNormal ICP
It is difficult to establish a universal“normal value” for ICP as it depends on
age, body posture and clinicalconditions.
8/16/2019 ICP Waveform Analysis J Ball 2004
10/16
The ICP WaveformThe ICP Waveform• P1 (percussion wave)
– sharp peak and a fairly
constant amplitude.
• P2 (tidal wave)
– ends on the dicrotic
notch.
• P3 (dicrotic wave)
– follows the dicroticnotch.
– Influenced by
• 3 peaks
• relation to the arterial &
venous pulse waveforms.
North B, in ‘Head Injury’ Ed. Reilly & Bullock, 1997
8/16/2019 ICP Waveform Analysis J Ball 2004
11/16
Increase waveform amplitude (P2)
(rounding of ICP waveform due to
increase in later waveform components)
↑ venous volume
Hypoventilation
Venous compression
Increase waveform amplitude (P1)↑ BP (hypertension)
Increase/ decrease waveform amplitude
Little change in waveform components
↑ CSF volume
Increase waveform amplitude (P2)↑ Mass lesion
Waveform changesCondition that
↑ ICP
adapted from C.J Kirkness et. al, 2000, 32;5, 273.
8/16/2019 ICP Waveform Analysis J Ball 2004
12/16
Interpretation of ICPInterpretation of ICP
• Elevation of P2
• suggests poor compliance
• predictive of poor outcome C.J Kirkness et. al, 2000, 32;5, 273.
8/16/2019 ICP Waveform Analysis J Ball 2004
13/16
The ICP WaveformThe ICP Waveform
• related to
– cardiac cycle : within individual waves
– respiratory cycle : between consecutive waves
North B, in ‘Head Injury’ Ed. Reilly & Bullock, 1997
8/16/2019 ICP Waveform Analysis J Ball 2004
14/16
ICPICP wavetrendswavetrends :: ‘‘ A A’’ waveswaves• Waves that plateau as high as 30-70mmhg and remain elevated for
as long as 20 minutes indicate that CPP is being significantly
compromised.
Muller et al. Pan Arab Journal of Neurosurgery 2000 4;2.
8/16/2019 ICP Waveform Analysis J Ball 2004
15/16
SummarySummary
• Visual assessment of the ICP waveform
can provide information about decreasedintracranial compliance and altered
intracranial dynamics :
• Increased amplitude
• Elevated P2 and• Rounding of the waveform
• ‘A’ or plateau waves
8/16/2019 ICP Waveform Analysis J Ball 2004
16/16
ReferencesReferences• Kirkness CJ et al. (2000)
Intracranial Pressure Waveform Analysis: Clinical and ResearchImpications.
Journal of Neuroscience Nursing 32:5
• Czosnyka M & Pickard JD (2004)Monitoring and Interpretation of Intracranial Pressure.
Journal of Neurology Neurosurgery & Psychiatry 75:813-821
• North B (1997)Intracranial Pressure Monitoring
in Reilly & Bullock (eds) Head Injury, Chapman & Hall.
• Muller et al. (2000)Intracranial Pressure (ICP) and Cerebrospinal Fluid (CSF)
DynamicsPan Arab Journal of Neurosurgery 2000 4;2.