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	<title>Neurosurgery Blog &#187; intracranial pressure</title>
	<atom:link href="http://www.neurosurgery-blog.com/archives/tag/intracranial-pressure/feed" rel="self" type="application/rss+xml" />
	<link>http://www.neurosurgery-blog.com</link>
	<description>Daily bibliographic and video review of the Neurosurgery Department. La Fe University Hospital. Valencia, Spain</description>
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		<title>A Randomized and Blinded Single-Center Trial Comparing the Effect of Intracranial Pressure and Intracranial Pressure Wave Amplitude-Guided Intensive Care Management on Early Clinical State and 12-Month Outcome in Patients With Aneurysmal Subarachnoid Hemorrhage</title>
		<link>http://www.neurosurgery-blog.com/archives/3386</link>
		<comments>http://www.neurosurgery-blog.com/archives/3386#comments</comments>
		<pubDate>Sun, 13 Nov 2011 23:00:06 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Outcome]]></category>
		<category><![CDATA[Randomized clinical trial]]></category>
		<category><![CDATA[Vascular]]></category>
		<category><![CDATA[Acute clinical state]]></category>
		<category><![CDATA[Intensive care management]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Intracranial wave amplitude]]></category>
		<category><![CDATA[Subarachnoid hemorrhage]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=3386</guid>
		<description><![CDATA[Neurosurgery 69:1105–1115, 2011 DOI: 10.1227/NEU.0b013e318227e0e1
In patients with aneurysmal subarachnoid hemorrhage (SAH), preliminary results indicate that the amplitude of the single intracranial pressure (ICP) wave is a better predictor of the early clinical state and 6-month outcome than the mean ICP.
OBJECTIVE: To perform a randomized and blinded single-center trial comparing the effect of mean ICP vs [...]]]></description>
			<content:encoded><![CDATA[<p style="text-align: justify;"><strong><a href="http://www.neurosurgery-blog.com/wp-content/uploads/2011/11/A_Randomized_and_Blinded_Single_Center_Trial.jpg"><img class="alignleft size-thumbnail wp-image-3390" title="A_Randomized_and_Blinded_Single_Center_Trial" src="http://www.neurosurgery-blog.com/wp-content/uploads/2011/11/A_Randomized_and_Blinded_Single_Center_Trial-150x150.jpg" alt="" width="150" height="150" /></a>Neurosurgery 69:1105–1115, 2011 DOI: 10.1227/NEU.0b013e318227e0e1</strong></p>
<p style="text-align: justify;"><strong></strong>In patients with aneurysmal subarachnoid hemorrhage (SAH), preliminary results indicate that the amplitude of the single intracranial pressure (ICP) wave is a better predictor of the early clinical state and 6-month outcome than the mean ICP.</p>
<p style="text-align: justify;">OBJECTIVE: To perform a randomized and blinded single-center trial comparing the effect of mean ICP vs mean ICP wave amplitude (MWA)-guided intensive care management on early clinical state and outcome in patients with aneurysmal SAH.</p>
<p style="text-align: justify;">METHODS: Patients were randomized to 2 different types of ICP management: maintenance of mean ICP less than 20 mm Hg and MWA less than 5mm Hg. Early clinical state was assessed daily using the Glasgow Coma Scale. The primary efficacy variable was 12-month outcome in terms of the Rankin Stroke Score.</p>
<p style="text-align: justify;">RESULTS: Ninety-seven patients were included in the study. There were no significant differences in treatment between the 2 groups apart from a larger volume of cerebrospinal fluid drained during week 1 in the MWA group. There was a tendency toward higher Glasgow Coma Scale scores in the MWA group during weeks 1 (P = .08) and 2 (P = .07). Outcome in terms of Rankin Stroke Score at 12 months was significantly better in the MWA group (P &lt; .05).</p>
<p style="text-align: justify;">CONCLUSION: This randomized and blinded trial disclosed a significant better primary efficacy variable (Rankin Stroke Score after 12 months) in the MWA patient group. We suggest that proactive intensive care management with MWA-tailored cerebrospinal fluid drainage during the first week improves aneurysmal SAH outcome.</p>
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		<item>
		<title>Benign external hydrocephalus: a review, with emphasis on management</title>
		<link>http://www.neurosurgery-blog.com/archives/2815</link>
		<comments>http://www.neurosurgery-blog.com/archives/2815#comments</comments>
		<pubDate>Mon, 27 Jun 2011 22:00:00 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Developmental Malformations]]></category>
		<category><![CDATA[hydrocephalus]]></category>
		<category><![CDATA[Communicating hydrocephalus]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Macrocephaly]]></category>
		<category><![CDATA[Outcome studies]]></category>
		<category><![CDATA[subarachnoid space]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=2815</guid>
		<description><![CDATA[Neurosurg Rev. DOI 10.1007/s10143-011-0327-4
Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search [...]]]></description>
			<content:encoded><![CDATA[<p><strong><a href="http://www.neurosurgery-blog.com/wp-content/uploads/2011/06/Benign-external-hydrocephalus_-review1.jpg"><img class="alignleft size-thumbnail wp-image-2821" title="Benign external hydrocephalus_ review" src="http://www.neurosurgery-blog.com/wp-content/uploads/2011/06/Benign-external-hydrocephalus_-review1-150x150.jpg" alt="" width="150" height="150" /></a>Neurosurg Rev. DOI 10.1007/s10143-011-0327-4</strong></p>
<p style="text-align: justify;">Benign external hydrocephalus in infants, characterized by macrocephaly and typical neuroimaging findings, is considered as a self-limiting condition and is therefore rarely treated. This review concerns all aspects of this condition: etiology, neuroimaging, symptoms and clinical findings, treatment, and outcome, with emphasis on management. The review is based on a systematic search in the Pubmed and Web of Science databases. The search covered various forms of hydrocephalus, extracerebral fluid, and macrocephaly. Studies reporting small children with idiopathic external hydrocephalus were included, mostly focusing on the studies reporting a long-term outcome.</p>
<p style="text-align: justify;">A total of 147 studies are included, the majority however with a limited methodological quality. Several theories regarding pathophysiology and various symptoms, signs, and clinical findings underscore the heterogeneity of the condition. Neuroimaging is important in the differentiation between external hydrocephalus and similar conditions. A transient delay of psychomotor development is commonly seen during childhood. A long-term outcome is scarcely reported, and the results are varying.</p>
<p style="text-align: justify;">Although most children with external hydrocephalus seem to do well both initially and in the long term, a substantial number of patients show temporary or permanent psychomotor delay. To verify that this truly is a benign condition, we suggest that future research on external hydrocephalus should focus on the long-term effects of surgical treatment as opposed to conservative management.</p>
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		<title>Guidelines for the Management of Spontaneous Intracerebral Hemorrhage</title>
		<link>http://www.neurosurgery-blog.com/archives/1554</link>
		<comments>http://www.neurosurgery-blog.com/archives/1554#comments</comments>
		<pubDate>Tue, 21 Sep 2010 04:00:10 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Clinical Guide]]></category>
		<category><![CDATA[Evidence-based]]></category>
		<category><![CDATA[Vascular]]></category>
		<category><![CDATA[meta-analysis]]></category>
		<category><![CDATA[AHA Scientific Statements]]></category>
		<category><![CDATA[diagnosis]]></category>
		<category><![CDATA[hydrocephalus]]></category>
		<category><![CDATA[intracerebral  hemorrhage]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Surgery]]></category>
		<category><![CDATA[treatment]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=1554</guid>
		<description><![CDATA[Stroke. 2010;41:2108-2129. DOI: 10.1161/STR.0b013e3181ec611b
Purpose—The aim of this guideline is to present current and comprehensive recommendations for the diagnosis and treatment of acute spontaneous intracerebral hemorrhage.
Methods—A formal literature search of MEDLINE was performed. Data were synthesized with the use of evidence tables. Writing committee members met by teleconference to discuss data-derived recommendations. The American Heart Association [...]]]></description>
			<content:encoded><![CDATA[<p><strong><a href="http://www.neurosurgery-blog.com/wp-content/uploads/2010/09/ICHGuidelines.jpg"><img class="alignleft size-thumbnail wp-image-1553" title="ICHGuidelines" src="http://www.neurosurgery-blog.com/wp-content/uploads/2010/09/ICHGuidelines-150x150.jpg" alt="" width="120" height="120" /></a>Stroke. 2010;41:2108-2129. DOI: 10.1161/STR.0b013e3181ec611b</strong></p>
<p style="text-align: justify;">Purpose—The aim of this guideline is to present current and comprehensive recommendations for the diagnosis and treatment of acute spontaneous intracerebral hemorrhage.</p>
<p style="text-align: justify;">Methods—A formal literature search of MEDLINE was performed. Data were synthesized with the use of evidence tables. Writing committee members met by teleconference to discuss data-derived recommendations. The American Heart Association Stroke Council’s Levels of Evidence grading algorithm was used to grade each recommendation. Prerelease review of the draft guideline was performed by 6 expert peer reviewers and by the members of the Stroke Council Scientific Statements Oversight Committee and Stroke Council Leadership Committee. It is intended that this guideline be fully updated in 3 years’ time.</p>
<p style="text-align: justify;">Results—Evidence-based guidelines are presented for the care of patients presenting with intracerebral hemorrhage. The focus was subdivided into diagnosis, hemostasis, blood pressure management, inpatient and nursing management, preventing medical comorbidities, surgical treatment, outcome prediction, rehabilitation, prevention of recurrence, and future considerations.</p>
<p style="text-align: justify;">Conclusions—Intracerebral hemorrhage is a serious medical condition for which outcome can be impacted by early, aggressive care. The guidelines offer a framework for goal-directed treatment of the patient with intracerebral hemorrhage.</p>
]]></content:encoded>
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		<item>
		<title>Transcranial Doppler Pulsatility Index: Not an Accurate Method to Assess Intracranial Pressure</title>
		<link>http://www.neurosurgery-blog.com/archives/1139</link>
		<comments>http://www.neurosurgery-blog.com/archives/1139#comments</comments>
		<pubDate>Mon, 21 Jun 2010 04:00:33 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Outcome]]></category>
		<category><![CDATA[Technology]]></category>
		<category><![CDATA[Trauma]]></category>
		<category><![CDATA[Blood flow velocity]]></category>
		<category><![CDATA[hydrocephalus]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[middle cerebral artery]]></category>
		<category><![CDATA[Pulsatility index]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=1139</guid>
		<description><![CDATA[
Neurosurgery 66 (6):1050–1057.
DOI 10.1227/01.NEU.0000369519.35932.F2

Transcranial Doppler sonography (TCD) assessment of intracranial blood flow velocity has been suggested to accurately determine intracranial pressure (ICP).
OBJECTIVE: We attempted to validate this method in patients with communicating cerebrospinal fluid systems using predetermined pressure levels.
METHODS: Ten patients underwent a lumbar infusion test, applying 4 to 5 preset ICP levels. On each level, [...]]]></description>
			<content:encoded><![CDATA[<div id="ej-article-box-text1-article-box-text">
<div style="text-align: left;"><a href="http://www.neurosurgery-blog.com/wp-content/uploads/2010/06/PI1.jpg"><img class="alignleft size-medium wp-image-1142" title="PI" src="http://www.neurosurgery-blog.com/wp-content/uploads/2010/06/PI1-300x279.jpg" alt="" width="113" height="104" /></a>Neurosurgery 66 (6):1050–1057.</div>
<div style="text-align: left;">DOI 10.1227/01.NEU.0000369519.35932.F2</div>
<div style="text-align: left;">
<p style="text-align: justify;">Transcranial Doppler sonography (TCD) assessment of intracranial blood flow velocity has been suggested to accurately determine intracranial pressure (ICP).</p>
<p style="text-align: justify;">OBJECTIVE: We attempted to validate this method in patients with communicating cerebrospinal fluid systems using predetermined pressure levels.</p>
<p style="text-align: justify;">METHODS: Ten patients underwent a lumbar infusion test, applying 4 to 5 preset ICP levels. On each level, the pulsatility index (PI) in the middle cerebral artery was determined by measuring the blood flow velocity using TCD. ICP was simultaneously measured with an intraparenchymal sensor. ICP and PI were compared using correlation analysis. For further understanding of the ICP-PI relationship, a mathematical model of the intracranial dynamics was simulated using a computer.</p>
<p style="text-align: justify;">RESULTS: The ICP-PI regression equation was based on data from 8 patients. For 2 patients, no audible Doppler signal was obtained. The equation was ICP = 23*PI + 14 (R2 = 0.22, P &lt; .01, N = 35). The 95% confidence interval for a mean ICP of 20 mm Hg was −3.8 to 43.8 mm Hg. Individually, the regression coefficients varied from 42 to 90 and the offsets from −32 to +3. The mathematical simulations suggest that variations in vessel compliance, autoregulation, and arterial pressure have a serious effect on the ICP-PI relationship.</p>
<p style="text-align: justify;">CONCLUSIONS: The in vivo results show that PI is not a reliable predictor of ICP. Mathematical simulations indicate that this is caused by variations in physiological parameters.</p>
</div>
</div>
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		<item>
		<title>Is ventriculomegaly in idiopathic normal pressure hydrocephalus associated with a transmantle gradient in pulsatile intracranial pressure?</title>
		<link>http://www.neurosurgery-blog.com/archives/1130</link>
		<comments>http://www.neurosurgery-blog.com/archives/1130#comments</comments>
		<pubDate>Thu, 17 Jun 2010 04:00:44 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[hydrocephalus]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Intracranial pulsatility]]></category>
		<category><![CDATA[Pressure gradient]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=1130</guid>
		<description><![CDATA[Acta Neurochir (2010) 152:989–995. DOI 10.1007/s00701-010-0605-x
Purpose: In patients with idiopathic normal pressure hydrocephalus (iNPH) and ventriculomegaly, examine whether there is a gradient in pulsatile intracranial pressure (ICP) from within the cerebrospinal fluid (CSF) of cerebral ventricles (ICPIV) to the subdural (ICPSD) compartment. We hypothesized that pulsatile ICP is higher within the ventricular CSF.
Methods The material [...]]]></description>
			<content:encoded><![CDATA[<p style="text-align: left;"><a href="http://www.neurosurgery-blog.com/wp-content/uploads/2010/06/iNPH.jpg"><img class="alignleft size-thumbnail wp-image-1131" title="iNPH" src="http://www.neurosurgery-blog.com/wp-content/uploads/2010/06/iNPH-150x150.jpg" alt="" width="120" height="120" /></a>Acta Neurochir (2010) 152:989–995. DOI 10.1007/s00701-010-0605-x</p>
<p style="text-align: justify;"><strong>Purpose</strong>: In patients with idiopathic normal pressure hydrocephalus (iNPH) and ventriculomegaly, examine whether there is a gradient in pulsatile intracranial pressure (ICP) from within the cerebrospinal fluid (CSF) of cerebral ventricles (ICPIV) to the subdural (ICPSD) compartment. We hypothesized that pulsatile ICP is higher within the ventricular CSF.</p>
<p style="text-align: justify;"><strong>Methods</strong> The material includes 10 consecutive iNPH patients undergoing diagnostic ICP monitoring as part of pre-operative work-up. Eight patients had simultaneous ICPIV and ICPSD signals, and two patients had simultaneous signals from the lateral ventricle (ICPIV) and the brain parenchyma (ICPPAR). Intracranial pulsatility was characterized by the wave amplitude, rise time, and rise time coefficient; static ICP was characterized by mean ICP.</p>
<p style="text-align: justify;"><strong>Results</strong> None of the patients demonstrated gradients in pulsatile ICP, that is, we found no evidence of higher pulsatile ICP within the CSF of the cerebral ventricles (ICPIV), as compared to either the subdural (ICPSD) compartment or within the brain parenchyma (ICPPAR). During ventricular infusion testing in one patient, the ventricular ICP (ICPIV) was artificially increased, but this increase in ICPIV produced no gradient in pulsatile ICP from the ventricular CSF (ICPIV) to the parenchyma (ICPPAR).</p>
<p style="text-align: justify;"><strong>Conclusions</strong>: In this cohort of iNPH patients, we found no evidence of transmantle gradient in pulsatile ICP. The data gave no support to the hypothesis that pulsatile ICP is higher within the CSF of the cerebral ventricles (ICPIV) than within the subdural (ICPSD) compartment or the brain parenchyma (ICPPAR) in iNPH patients.</p>
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		<item>
		<title>Cerebral Hemodynamic Changes in Severe Head Injury Patients Undergoing Decompressive Craniectomy</title>
		<link>http://www.neurosurgery-blog.com/archives/428</link>
		<comments>http://www.neurosurgery-blog.com/archives/428#comments</comments>
		<pubDate>Thu, 17 Dec 2009 05:55:44 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Trauma]]></category>
		<category><![CDATA[decompressive craniectomy]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Outcome]]></category>
		<category><![CDATA[transcranial Doppler]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=428</guid>
		<description><![CDATA[J Neurosurg Anesthesiol 2009;21:339–345
 
Objective: To assess the intracranial hemodynamic modifica- tions induced by a decompressive craniectomy (DC) after severe traumatic brain injury (TBI), using transcranial Doppler (TCD) ultrasonography and intracranial pressure (ICP) sensor. Mor- tality rate and neurological outcomes were also evaluated after this procedure.
Design: A prospective study was carried out on 26 TBI [...]]]></description>
			<content:encoded><![CDATA[<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">J Neurosurg Anesthesiol 2009;21:339–345</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica; min-height: 14.0px;"><span style="letter-spacing: 0.0px;"> </span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Objective: To assess the intracranial hemodynamic modifica- tions induced by a decompressive craniectomy (DC) after severe traumatic brain injury (TBI), using transcranial Doppler (TCD) ultrasonography and intracranial pressure (ICP) sensor. Mor- tality rate and neurological outcomes were also evaluated after this procedure.</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Design: A prospective study was carried out on 26 TBI patients, measuring transcranial Doppler and ICP before, immediately after, and 48 hours after the DC, allowing for statistical analysis of hemodynamic changes. The mortality rate and the neuro- logical outcomes were assessed.</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Measurements and Results: After DC, ICP decreased from 37±17 to 20±13mm Hg (P=0.0003). The global cerebral blood flow was modified with diastolic velocities rising from 23±15 to 31±13cm/s (P=0.0038) and a pulsatility index decreasing from 1.70±0.66 to 1.18±0.37 (P=0.0012). This normalization of the global cerebral hemodynamics after the DC was immediate, symmetric, and constant during the first 48 hours. Outcome was evaluated at 6 months: good recovery or moderate disability was observed in 11 patients (42%), persistent vegetative state in 7 patients (27%), and 8 patients died (31%).</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Conclusions: The DC results in a significant, immediate, and durable improvement of ICP associated with a normalization of cerebral blood flow velocities in most TBI patients with refractory intracranial hypertension.</span></p>
<div style="text-align: justify;"><span style="font-family: Helvetica, 'Times New Roman', 'Bitstream Charter', Times, serif; font-size: small;"><span style="line-height: normal;"><br />
</span></span></div>
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		<item>
		<title>Relationship between intracranial hemodynamics and microdialysis markers of energy metabolism and glutamate-glutamine turnover in patients with subarachnoid hemorrhage</title>
		<link>http://www.neurosurgery-blog.com/archives/383</link>
		<comments>http://www.neurosurgery-blog.com/archives/383#comments</comments>
		<pubDate>Fri, 27 Nov 2009 05:55:22 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Vascular]]></category>
		<category><![CDATA[glutamate]]></category>
		<category><![CDATA[glutamine]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[lactate]]></category>
		<category><![CDATA[microdialysis]]></category>
		<category><![CDATA[pyruvate]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=383</guid>
		<description><![CDATA[J Neurosurg 111:910–915, 2009.DOI: 10.3171/2008.8.JNS0889
 
The aim of this study was to explore the relationship between hemodynamics (intracranial and systemic) and brain tissue energy metabolism, and between hemodynamics and glutamate (Glt)-glutamine (Gln) cycle activity.
Methods. Brain interstitial levels of lactate, pyruvate, Glt, and Gln were prospectively monitored in the neurointensive care unit for more than 3600 [...]]]></description>
			<content:encoded><![CDATA[<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">J Neurosurg 111:910–915, 2009.DOI: 10.3171/2008.8.JNS0889</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica; min-height: 14.0px;"><span style="letter-spacing: 0.0px;"> </span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">The aim of this study was to explore the relationship between hemodynamics (intracranial and systemic) and brain tissue energy metabolism, and between hemodynamics and glutamate (Glt)-glutamine (Gln) cycle activity.</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Methods. Brain interstitial levels of lactate, pyruvate, Glt, and Gln were prospectively monitored in the neurointensive care unit for more than 3600 hours using intracerebral microdialysis in 33 patients with subarachnoid hemorrhage (SAH). Intracranial pressure (ICP), mean arterial blood pressure, and cerebral perfusion pressure (CPP) were recorded using a digitalized system.</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Results. Interstitial Gln and pyruvate correlated with CPP (r = 0.25 and 0.24, respectively). Intracranial pressure negatively correlated with Gln (r = −0.29) and the Gln/Glt ratio (r = –0.40). Levels of Gln and pyruvate and the Gln/Glt ratio were higher and levels of Glt and lactate and the lactate/pyruvate ratio were lower during periods of decreased ICP (≤ 10 mm Hg) as compared with values in periods of elevated ICP (&gt; 10 mm Hg). In 3 patients, a poor clinical condition was attributed to high ICP levels (range 15–25 mm Hg). When CSF drainage was increased and the ICP was lowered to 10 mm Hg, there was an instantaneous sharp increase in interstitial Glt and pyruvate in these 3 patients.</span></p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;"><span style="letter-spacing: 0.0px;">Conclusions. Increasing interstitial Gln and pyruvate levels appear to be favorable signs associated with improved CPP and low ICP. The authors suggest that this pattern indicates an energy metabolic situation allowing augmented astrocytic energy metabolism with accelerated Glt uptake and Gln synthesis. Moreover, their data raised the question of whether patients with SAH and moderately elevated ICP (15–20 mm Hg) would benefit from CSF drainage at lower pressure levels than what is usually indicated in current clinical protocols.</span></p>
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		<title>Cerebral Hemodynamic Changes in Severe Head Injury Patients Undergoing Decompressive Craniectomy</title>
		<link>http://www.neurosurgery-blog.com/archives/359</link>
		<comments>http://www.neurosurgery-blog.com/archives/359#comments</comments>
		<pubDate>Mon, 16 Nov 2009 05:55:40 +0000</pubDate>
		<dc:creator>cba</dc:creator>
				<category><![CDATA[Surgical technique]]></category>
		<category><![CDATA[Trauma]]></category>
		<category><![CDATA[decompressive craniectomy]]></category>
		<category><![CDATA[intracranial pressure]]></category>
		<category><![CDATA[Outcome]]></category>
		<category><![CDATA[transcranial Doppler]]></category>

		<guid isPermaLink="false">http://www.neurosurgery-blog.com/?p=359</guid>
		<description><![CDATA[J Neurosurg Anesthesiol 2009;21:339–345

A prospective study was carried out on 26 TBI patients, measuring transcranial Doppler and ICP before, immediately after, and 48 hours after the DC, allowing for statistical analysis of hemodynamic changes. The mortality rate and the neuro- logical outcomes were assessed.
Measurements and Results: After DC, ICP decreased from 37±17 to 20±13mm Hg [...]]]></description>
			<content:encoded><![CDATA[<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;">J Neurosurg Anesthesiol 2009;21:339–345</p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;">
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;">A prospective study was carried out on 26 TBI patients, measuring transcranial Doppler and ICP before, immediately after, and 48 hours after the DC, allowing for statistical analysis of hemodynamic changes. The mortality rate and the neuro- logical outcomes were assessed.</p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;">Measurements and Results: After DC, ICP decreased from 37±17 to 20±13mm Hg (P=0.0003). The global cerebral blood flow was modified with diastolic velocities rising from 23±15 to 31±13cm/s (P=0.0038) and a pulsatility index decreasing from 1.70±0.66 to 1.18±0.37 (P=0.0012). This normalization of the global cerebral hemodynamics after the DC was immediate, symmetric, and constant during the first 48 hours. Outcome was evaluated at 6 months: good recovery or moderate disability was observed in 11 patients (42%), persistent vegetative state in 7 patients (27%), and 8 patients died (31%).</p>
<p style="margin: 0.0px 0.0px 0.0px 0.0px; text-align: justify; font: 12.0px Helvetica;">Conclusions: The DC results in a significant, immediate, and durable improvement of ICP associated with a normalization of cerebral blood flow velocities in most TBI patients with refractory intracranial hypertension.</p>
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