"Optimal cerebral perfusion pressure" in poor grade patients after subarachnoid hemorrhage.
BACKGROUND
Cerebrovascular pressure reactivity depends on cerebral perfusion pressure (CPP), with the optimal CPP (CPPopt) defined as pressure at which cerebrovascular reactivity is functioning optimally, reaching minimal value of pressure reactivity index (PRx). The study investigates the association between vasospasm, PRx, and CPPopt in poor grade patients (WFNS 4&5) after subarachnoid hemorrhage (SAH).


METHODS
Data of intracranial pressure (ICP), arterial blood pressure (ABP), and flow velocities (FV) in the Middle Cerebral Artery (MCA) on transcranial Doppler from 42 SAH patients were analyzed retrospectively. PRx was calculated as a correlation coefficient between 10 s mean values of ABP and ICP calculated over a moving 3 min window. Data recorded during the first 48 h were available in 25 cases and during the first 3 days in 29 patients. Recordings obtained from day 4 to day 24 were available in 23 patients.


RESULTS
PRx at optimal CPP measured during the first 48 h showed better cerebrovascular reactivity in patients who were alive at 3 months after ictus than in those who died (PRx value -0.17 +/- 0.05 vs. 0.1 +/- 0.09; P < 0.01). PRx below zero at CPPopt during the first 48 h had 87.5% positive predictive value for survival. CPPopt was lower before than during vasospasm (78 +/- 3 mmHg, N = 29 vs. 98 +/- 4 mmHg; N = 17, P < 0.0001). The overall correlation between CPPopt and Lindegaard ratio was positive (R = 0.39; P < 0.01; N = 45).


CONCLUSIONS
Most WFNS 4&5 grade SAH patients with PRx below zero at optimal CPP during the first 48 h after ictus survived. Optimal CPP increases during vasospasm.
Bijlenga
Philippe
P
Academic Neurosurgical Unit, Department of Neurosurgery, Addenbrooke's Hospital, University of Cambridge, Cambridge, CB2 0QQ, UK.
Czosnyka
Marek
M
Budohoski
Karol P
KP
Soehle
Martin
M
Pickard
John D
JD
Kirkpatrick
Peter J
PJ
Smielewski
Peter
P
D001783:Blood Flow Velocity; D001794:Blood Pressure; D002560:Cerebrovascular Circulation; D006801:Humans; D020768:Middle Cerebral Artery / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013345:Subarachnoid Hemorrhage / Q000150:complications / Q000401:mortality / Q000503:physiopathology*; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial; D020301:Vasospasm, Intracranial / Q000000981:diagnostic imaging / Q000209:etiology
Stroke. 1996 Apr;27(4):625-9
8614919
Acta Neurochir Suppl. 1999;72:59-71
10337413
Crit Care Med. 2001 Jan;29(1):158-63
11176177
Neurosurgery. 1999 Jun;44(6):1237-47; discussion 1247-8
10371622
Acta Neurochir Suppl. 2005;95:43-9
16463818
AJNR Am J Neuroradiol. 2006 Jan;27(1):26-34
16418351
J Neurosurg. 1982 Feb;56(2):186-96
7054427
J Neurosurg. 1996 Apr;84(4):648-54
8613858
Ann Neurol. 1983 Dec;14(6):599-608
6651248
Stroke. 1996 Oct;27(10):1829-34
8841340
J Neurosurg. 1978 Feb;48(2):173-8
624965
N Engl J Med. 1997 Jan 2;336(1):28-40
8970938
Neurol Res. 1994 Feb;16(1):40-4
7913530
Stroke. 1982 Sep-Oct;13(5):601-11
6812243
J Neurosurg. 1990 Jul;73(1):18-36
2191090
Pharmacol Ther. 2005 Jan;105(1):23-56
15626454
J Neurol Neurosurg Psychiatry. 1979 Oct;42(10):899-903
117081
Stroke. 2001 Oct;32(10):2292-8
11588316
Stroke. 2005 Aug;36(8):1627-32
16049199
Neurosurgery. 2000 Oct;47(4):819-25; discussions 825-6
11014420
Neurology. 1998 May;50(5):1413-8
9595997
J Neurosurg. 1984 Jan;60(1):37-41
6689726
Lancet. 2007 Jan 27;369(9558):306-18
17258671
Acta Neurochir (Wien). 1991;108(1-2):7-14
2058430
Neurosurgery. 1982 Sep;11(3):337-43
7133349
Anesth Analg. 2004 Apr;98(4):1133-1139
15041613
J Neurosurg. 1993 Oct;79(4):490-3
8410215
Acta Neurochir (Wien). 2004 Feb;146(2):131-41
14963745
J Neurosurg. 2004 Feb;100(2):287-94
15086237
Stroke. 1989 Jan;20(1):45-52
2492126
Stroke. 2003 Oct;34(10):2404-9
12947157
Med Clin North Am. 1951 Sep;35(5):1457-74
14862567
Crit Care Med. 2002 Apr;30(4):733-8
11940737