Predictive value of intracranial flow pulsatility for intracranial hypertension in adults with subarachnoid hemorrhage

Joseph L. Nates, Adatola Talabi, Andrei Alexandrov

Research output: Contribution to journalArticle

Abstract

Introduction: Transcranial Doppler (TCD) noninvasively measures pulsatility of flow in basal cerebral arteries which has been previously correlated to intracranial pressure (ICP) changes. The purpose of this study was to evaluate the predictive value of TCD in adults with markedly elevated ICP with a view to develop criteria for detecting ICP changes due to hydrocephalus or mass-effect. Methods: TCD was performed daily to monitor vasospasm in adult patients with subarachnoid hemorrhage (SAH). We compared the highest pulsatility index (PI) on TCD to simultaneous ventricular ICP measurements. PI < 1.2 was considered normal, i.e. showing a low resistance flow. PI ≥ 1.2 was considered abnormal indicating increased ICP ≥ 20 mm Hg. Ventriculostomy was performed when clinically indicated and independent of TCD findings. Patients with distal vasospasm were excluded from the analysis. Results: In 42 patients, 17 had true positive, 21 had true negative TCD findings. False-positive and false-negative TCD results were found in 4 patients. The accuracy parameters were: sensitivity 89% (95% CI's 79-99%); specificity 91% (82-100%); PPV 89% (79-99%); NPV 91% (82-100%). False-positive TCD studies were due to relatively low MAP with mildly elevated ICP (i.e. 10-18 mm Hg), bradicardia, or chronic hypertension in elderly patients. False-negative TCD's were found in patients with relatively high MAP and/or compartmental ICP increase. Conclusions: Pulsatility index ≥ 1.2 is both sensitive and specific for ICP elevation above 20 mm Hg and can be used for noninvasive monitoring of adult patients. In select individuals, TCD helps refine invasive ICP measurements and can be helpful in early detection of hydrocephalus or shunt malfunction.

Original languageEnglish (US)
JournalCritical care medicine
Volume27
Issue number1 SUPPL.
StatePublished - Dec 1 1999

Fingerprint

Intracranial Hypertension
Subarachnoid Hemorrhage
Intracranial Pressure
Hydrocephalus
Ventriculostomy
Cerebral Arteries
Physiologic Monitoring
Ventricular Pressure
Hypertension

All Science Journal Classification (ASJC) codes

  • Critical Care and Intensive Care Medicine

Cite this

Predictive value of intracranial flow pulsatility for intracranial hypertension in adults with subarachnoid hemorrhage. / Nates, Joseph L.; Talabi, Adatola; Alexandrov, Andrei.

In: Critical care medicine, Vol. 27, No. 1 SUPPL., 01.12.1999.

Research output: Contribution to journalArticle

@article{63babd60233944d499739a2fd756a10c,
title = "Predictive value of intracranial flow pulsatility for intracranial hypertension in adults with subarachnoid hemorrhage",
abstract = "Introduction: Transcranial Doppler (TCD) noninvasively measures pulsatility of flow in basal cerebral arteries which has been previously correlated to intracranial pressure (ICP) changes. The purpose of this study was to evaluate the predictive value of TCD in adults with markedly elevated ICP with a view to develop criteria for detecting ICP changes due to hydrocephalus or mass-effect. Methods: TCD was performed daily to monitor vasospasm in adult patients with subarachnoid hemorrhage (SAH). We compared the highest pulsatility index (PI) on TCD to simultaneous ventricular ICP measurements. PI < 1.2 was considered normal, i.e. showing a low resistance flow. PI ≥ 1.2 was considered abnormal indicating increased ICP ≥ 20 mm Hg. Ventriculostomy was performed when clinically indicated and independent of TCD findings. Patients with distal vasospasm were excluded from the analysis. Results: In 42 patients, 17 had true positive, 21 had true negative TCD findings. False-positive and false-negative TCD results were found in 4 patients. The accuracy parameters were: sensitivity 89{\%} (95{\%} CI's 79-99{\%}); specificity 91{\%} (82-100{\%}); PPV 89{\%} (79-99{\%}); NPV 91{\%} (82-100{\%}). False-positive TCD studies were due to relatively low MAP with mildly elevated ICP (i.e. 10-18 mm Hg), bradicardia, or chronic hypertension in elderly patients. False-negative TCD's were found in patients with relatively high MAP and/or compartmental ICP increase. Conclusions: Pulsatility index ≥ 1.2 is both sensitive and specific for ICP elevation above 20 mm Hg and can be used for noninvasive monitoring of adult patients. In select individuals, TCD helps refine invasive ICP measurements and can be helpful in early detection of hydrocephalus or shunt malfunction.",
author = "Nates, {Joseph L.} and Adatola Talabi and Andrei Alexandrov",
year = "1999",
month = "12",
day = "1",
language = "English (US)",
volume = "27",
journal = "Critical Care Medicine",
issn = "0090-3493",
publisher = "Lippincott Williams and Wilkins",
number = "1 SUPPL.",

}

TY - JOUR

T1 - Predictive value of intracranial flow pulsatility for intracranial hypertension in adults with subarachnoid hemorrhage

AU - Nates, Joseph L.

AU - Talabi, Adatola

AU - Alexandrov, Andrei

PY - 1999/12/1

Y1 - 1999/12/1

N2 - Introduction: Transcranial Doppler (TCD) noninvasively measures pulsatility of flow in basal cerebral arteries which has been previously correlated to intracranial pressure (ICP) changes. The purpose of this study was to evaluate the predictive value of TCD in adults with markedly elevated ICP with a view to develop criteria for detecting ICP changes due to hydrocephalus or mass-effect. Methods: TCD was performed daily to monitor vasospasm in adult patients with subarachnoid hemorrhage (SAH). We compared the highest pulsatility index (PI) on TCD to simultaneous ventricular ICP measurements. PI < 1.2 was considered normal, i.e. showing a low resistance flow. PI ≥ 1.2 was considered abnormal indicating increased ICP ≥ 20 mm Hg. Ventriculostomy was performed when clinically indicated and independent of TCD findings. Patients with distal vasospasm were excluded from the analysis. Results: In 42 patients, 17 had true positive, 21 had true negative TCD findings. False-positive and false-negative TCD results were found in 4 patients. The accuracy parameters were: sensitivity 89% (95% CI's 79-99%); specificity 91% (82-100%); PPV 89% (79-99%); NPV 91% (82-100%). False-positive TCD studies were due to relatively low MAP with mildly elevated ICP (i.e. 10-18 mm Hg), bradicardia, or chronic hypertension in elderly patients. False-negative TCD's were found in patients with relatively high MAP and/or compartmental ICP increase. Conclusions: Pulsatility index ≥ 1.2 is both sensitive and specific for ICP elevation above 20 mm Hg and can be used for noninvasive monitoring of adult patients. In select individuals, TCD helps refine invasive ICP measurements and can be helpful in early detection of hydrocephalus or shunt malfunction.

AB - Introduction: Transcranial Doppler (TCD) noninvasively measures pulsatility of flow in basal cerebral arteries which has been previously correlated to intracranial pressure (ICP) changes. The purpose of this study was to evaluate the predictive value of TCD in adults with markedly elevated ICP with a view to develop criteria for detecting ICP changes due to hydrocephalus or mass-effect. Methods: TCD was performed daily to monitor vasospasm in adult patients with subarachnoid hemorrhage (SAH). We compared the highest pulsatility index (PI) on TCD to simultaneous ventricular ICP measurements. PI < 1.2 was considered normal, i.e. showing a low resistance flow. PI ≥ 1.2 was considered abnormal indicating increased ICP ≥ 20 mm Hg. Ventriculostomy was performed when clinically indicated and independent of TCD findings. Patients with distal vasospasm were excluded from the analysis. Results: In 42 patients, 17 had true positive, 21 had true negative TCD findings. False-positive and false-negative TCD results were found in 4 patients. The accuracy parameters were: sensitivity 89% (95% CI's 79-99%); specificity 91% (82-100%); PPV 89% (79-99%); NPV 91% (82-100%). False-positive TCD studies were due to relatively low MAP with mildly elevated ICP (i.e. 10-18 mm Hg), bradicardia, or chronic hypertension in elderly patients. False-negative TCD's were found in patients with relatively high MAP and/or compartmental ICP increase. Conclusions: Pulsatility index ≥ 1.2 is both sensitive and specific for ICP elevation above 20 mm Hg and can be used for noninvasive monitoring of adult patients. In select individuals, TCD helps refine invasive ICP measurements and can be helpful in early detection of hydrocephalus or shunt malfunction.

UR - http://www.scopus.com/inward/record.url?scp=33750810354&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=33750810354&partnerID=8YFLogxK

M3 - Article

AN - SCOPUS:33750810354

VL - 27

JO - Critical Care Medicine

JF - Critical Care Medicine

SN - 0090-3493

IS - 1 SUPPL.

ER -