Abstract:
:Temporal variability of parameters which describe dynamic cerebral autoregulation (CA), usually quantified by the short-term relationship between arterial blood pressure (BP) and cerebral blood flow velocity (CBFV), could result from continuous adjustments in physiological regulatory mechanisms or could be the result of artefacts in methods of measurement, such as the use of non-invasive measurements of BP in the finger. In 27 subjects (61+/-11 years old) undergoing coronary artery angioplasty, BP was continuously recorded at rest with the Finapres device and in the ascending aorta (Millar catheter, BP(AO)), together with bilateral transcranial Doppler ultrasound in the middle cerebral artery, surface ECG and transcutaneous CO(2). Dynamic CA was expressed by the autoregulation index (ARI), ranging from 0 (absence of CA) to 9 (best CA). Time-varying, continuous estimates of ARI (ARI(t)) were obtained with an autoregressive moving-average (ARMA) model applied to a 60 s sliding data window. No significant differences were observed in the accuracy and precision of ARI(t) between estimates derived from the Finapres and BP(AO). Highly significant correlations were obtained between ARI(t) estimates from the right and left middle cerebral artery (MCA) (Finapres r=0.60+/-0.20; BP(AO) r=0.56+/-0.22) and also between the ARI(t) estimates from the Finapres and BP(AO) (right MCA r=0.70+/-0.22; left MCA r=0.74+/-0.22). Surrogate data showed that ARI(t) was highly sensitive to the presence of noise in the CBFV signal, with both the bias and dispersion of estimates increasing for lower values of ARI(t). This effect could explain the sudden drops of ARI(t) to zero as reported previously. Simulated sudden changes in ARI(t) can be detected by the Finapres, but the bias and variability of estimates also increase for lower values of ARI. In summary, the Finapres does not distort time-varying estimates of dynamic CA obtained with a sliding window combined with an ARMA model, but further research is needed to confirm these findings in healthy subjects and to assess the influence of different physiological manoeuvres.
journal_name
Physiol Measjournal_title
Physiological measurementauthors
Panerai RB,Sammons EL,Smith SM,Rathbone WE,Bentley S,Potter JF,Samani NJdoi
10.1088/0967-3334/29/4/006subject
Has Abstractpub_date
2008-04-01 00:00:00pages
497-513issue
4eissn
0967-3334issn
1361-6579pii
S0967-3334(08)66176-6journal_volume
29pub_type
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journal_title:Physiological measurement
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更新日期:2004-02-01 00:00:00
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journal_title:Physiological measurement
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更新日期:2002-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/38/2/310
更新日期:2017-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/22/1/308
更新日期:2001-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab6ebb
更新日期:2020-03-06 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2004-06-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/2/006
更新日期:1993-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/24/2/310
更新日期:2003-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/009
更新日期:1993-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
doi:10.1088/0967-3334/25/6/n01
更新日期:2004-12-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/31/10/001
更新日期:2010-10-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/ab7cb5
更新日期:2020-04-20 00:00:00
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pub_type: 杂志文章
doi:10.1088/1361-6579/ab921e
更新日期:2020-07-01 00:00:00
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doi:10.1088/0967-3334/36/2/231
更新日期:2015-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章,随机对照试验
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更新日期:1996-11-01 00:00:00
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journal_title:Physiological measurement
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doi:10.1088/0967-3334/33/5/849
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journal_title:Physiological measurement
pub_type: 临床试验,杂志文章
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更新日期:2007-02-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/3/465
更新日期:2015-03-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/15/2/002
更新日期:1994-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaa749
更新日期:2018-03-23 00:00:00
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pub_type: 杂志文章
doi:10.1088/1361-6579/abb8bf
更新日期:2020-11-06 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/14/3/019
更新日期:1993-08-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/0967-3334/36/5/857
更新日期:2015-05-01 00:00:00
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journal_title:Physiological measurement
pub_type: 杂志文章
doi:10.1088/1361-6579/aaee19
更新日期:2018-12-07 00:00:00