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Raised intracranial pressure: keeping a lid on it UNSW John Myburgh MBBCh PhD FCICM The George Institute for Global Health St George Clinical School, University of New South Wales
Raised intracranial pressure:keeping a lid on it
UNSW
John MyburghMBBCh PhD FCICM
The George Institute for Global Health St George Clinical School, University of New South Wales
P (
mm
Hg
)
V (ml)1783, 1824
Monro-Kelly doctrineIntracranial volume remains constant at any given time
Bryan Jennett
Douglas Miller
Larry Marshall
1978
1979
1980
Fearnside: Br J Neurosurg 1992
Inflammatory modulation
Bayir: Crit Care Med 2003
Neuroprotective trials
Maas: Neurosurgery 1999
HIT I (n=351)HIT II (n=852)
HIT III (n=123)PEGSOD (n=463)Tirilizad (n=1128)
Triamcinolone (n=396)
HIT II tSAHTirilizad tSAH
Triamcinolone GCS 8+focal lesion
Neuroprotective agentsAll steroids
mean = 435
Rat / human model 20th centuryTake a young male rat.
Infuse alcohol or speed until intoxicated.
Throw rat at high speed into brick wall
Break its femur and pelvis.
Leave it lying in the corner for 1 hour.
Get resident to resuscitate it using albumin
Include an oesophageal intubation and hypoxia for 20m.
Get orthopod to fix femur and lose 20% blood volume.
Do a CT head, but don’t tell the researcher the results.
Get a resident to put in ICP monitor 6-36 hours after injury.
Do the intervention.
Random use of mannitol, hyperventilation, hypothermia, barbs
Count how many rats are dead after 1 week.
Randy Chesnut
Nino Stocchetti
Andrew Maas
www.braintrauma.org
2001, 2003, 2007
Critical pathway
BTF Guidelines 1st, 2nd editions
Tier 1
Critical pathway: proposed
Tier 2
Tier 3
Low dose mannitol
Normothermia
Decompressive craniectomyInduced hypothermia
Neuromuscular blockadeHigh dose mannitol
Hypertonic saline
Mild hypothermia (35-37)
BTF Guidelines Working Group: 2009
Rat / human model 21th centuryTake a rat of any age.
If young, infuse alcohol or speed until intoxicated.
If old, give warfarin and aspirin
Early intubation and resuscitation
Pan-scan and damage control surgery
Standardise ICP monitoring
Do the intervention.
Flog CPP with noradrenaline
Use hypothermia, barbiturates to keep ICP<20
Decompressive craniectomy if these don’t work
Keep going until the rat’s family tells you when to stop
Count how many rats are dead after 6 months.
Comparative data
ATBISGCS<9
SAFE TBIGCS<9
(Albumin)
SAFE TBIGCS<9(Saline)
n 363 160 158
Inception period 2000-2001 2001-2003 2001-2003
12-month mortality: n/N (%) 105/299 (35.1) 61/153 (39.9) 32/149 (21.5)
Myburgh J Trauma: 2008
Decompressive craniectomyIndication
Age
Diffuse vs mass lesion
Traumatic vs non-traumatic
Timing
Pre-emptive
Rescue
Trigger
CT / clinical
ICP
Technique
Bifrontal vs unilateral
Dura open vs closed
Outcome
Physiological
Death / functional outcome
Honeybul: Brian inj 2013
Jiang:J Neurotrauma: 2005
Multicentred RCT, blinded outcome adjudication
1998 – 2001
n=486
Age < 70
Clinical / CT triggers for decompression
Primary outcome: 6m GOS
Standard Limited
Jiang:J Neurotrauma: 2005
GR / MD SD / PVS Dead0
10
20
30
40
50
Standard DC (n=241))Limited DC (n=245)
6m GOS
%
0
10
20
30
40
50
Day
ICP
(m
mH
g)
Pre DC 1 day 3 days 7 days
Standard DC (n=36)Limited DC (n=47)
p=0.03
Cooper: New Eng J Med 2011
Multicentred RCT, blinded outcome adjudication
2002-2011
N=155 (age <60)
Age < 60; < 72h post injury
CT trigger: Diffuse injury
ICP trigger: >20 mmHg
Primary outcome: 6m GOS
vs Medical therapy
Cooper: New Eng J Med 2011
Unfavourable Favourable
70% 51%
OR: 2.21 95%CI 1.14 to 4.26; P=0.02
www.rescueicp.com
Multi-centre RCT, blinded outcome adjudication
366/400 patients recruited
Age 18-65
ICP>25 mmHg
Refractory to medical therapy (2nd tier)
Included evacuated mass lesions
Clinically directed decompression
Primary outcome: Discharge + 6m GOSE
Honeybul: Brian inj 2013
Decompression for TBI
Survivors with unfavourable outcomes
Survivors with favourable outcomesSurvivors with favourable outcomes
Honeybul: Brian inj 2013
Middle cerebral artery infarctionAge limited: <60y
Time limited: < 48 hours
Co-morbidity / non-dominant hemisphere
DECIMAL: n=38 (Germany)
DESTINY: n=32 (France) HAMLET: n=39 (Netherlands)
Hofmeijer: Lancet 2009
Middle cerebral artery infarction
Age limited: >60y
Time limited: < 48 hours
Low co-morbidity / non-dominant hemisphere
Juttler: NEJM 2014
Honeybul: Brian inj 2013
Decompression for non-TBI
Survivors with unfavourable outcomes
Survivors with favourable outcomes
Does Intensive Care improve outcome from TBI?
Chesnut: NEJM 2012
Multi-centred RCT, blinded outcome adjudication
2008-2011
N=324
Age >13 <60
GCS<9 , < 48h post injury
Pressure/monitoring: ICP >20 mmHg + 3-tiered protocol
Imaging/clinical exam: 3-tiered protocol
Primary outcome: composite functional outcome 6m
Chesnut: NEJM 2012
ICP monitoring group
Imaging/exam group
P=0.60
ICP(n=157)
ICE(n=167)
OR (95%CI) p
CFOS 56 (22-37) 53 (21-76) 1.09 (0.74 to 1.58) 0.49
Death 56/144 (39%) 67 (41%) 1.10 (0.77 to 1.57) 0.60
T H Huxley1825 - 1895
m“That the great tragedy of Science is the slaying of a beautiful hypothesis with an ugly fact”
Some concluding thoughts
Outcome from ABI is primarily determined by geography…
… and genetics
ICP is primarily an indicator of severity of injury
Treating ICP comes at a cost …
… saving the head, but killing the body…
… and those who care for the patient
Some concluding thoughts
Beware the therapeutic imperative to do what we can…
… and not what we should
