Document Detail


Preserved metabolic coupling and cerebrovascular reactivity during mild hypothermia after cardiac arrest.
MedLine Citation:
PMID:  20453643     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
OBJECTIVE: Although mild hypothermia improves outcome in patients after out-of-hospital cardiac arrest, the cardiodepressive effects of hypothermia may lead to secondary brain damage. This study was performed to assess the cerebral blood flow, cerebral oxygen extraction, and cerebrovascular reactivity to changes in partial pressure of carbon dioxide in the arterial blood in comatose patients after out-of-hospital cardiac arrest treated with mild hypothermia. DESIGN: Observational study. SETTING: Tertiary care university hospital. PATIENTS: Ten comatose patients after out-of-hospital cardiac arrest. INTERVENTIONS: All patients were cooled to 32-34 degrees C for 24 hrs. Cerebrovascular reactivity to changes in carbon dioxide in the arterial blood was measured after increasing or decreasing the minute ventilation by 20%. MEASUREMENTS AND MAIN RESULTS: Mean flow velocity in the middle cerebral artery and pulsatility index were measured by transcranial Doppler at 0, 3, 6, 9, 12, 18, 24, and 48 hrs after admission. Jugular bulb oxygenation was measured at the same intervals. Cerebrovascular reactivity to changes in carbon dioxide in the arterial blood was studied on admission to the intensive care unit and at 6, 12, 18, and 24 hrs by measurement of mean flow velocity in the middle cerebral artery and jugular bulb oxygenation. Mean flow velocity in the middle cerebral artery was low (30.3+/-9.5 cm/sec) on admission and remained relatively stable for the first 24 hrs. After rewarming, it increased to 67.5+/-33.0 cm/sec at 48 hrs after admission from 30.3+/-9.5 at admission (p=.009). Jugular bulb oxygenation at the start of the study was 66.2+/-8.5% and gradually increased to 82.9+/-4.9% at 48 hrs (p<.001). Regression analysis showed a significant correlation between changes in carbon dioxide in the arterial blood, mean flow velocity in the middle cerebral artery (p<.001) and jugular bulb oxygenation (p<.001). The mean percentage change in mean flow velocity in the middle cerebral artery was 3.6+/-2.9% per 1-mm Hg change of carbon dioxide in the arterial blood. CONCLUSIONS: The mean flow velocity in the middle cerebral artery, as a parameter of cerebral blood flow, was low during mild hypothermia, whereas cerebral oxygen extraction remained normal, suggesting decreased cerebral metabolic activity. We demonstrated that CO2 reactivity is preserved during hypothermia in these patients.
Authors:
Laurens L A Bisschops; Cornelia W E Hoedemaekers; Koen S Simons; Johannes G van der Hoeven
Related Documents :
12040263 - Five years of follow-up after elemental mercury self-poisoning.
15213823 - Use of inherently conducting polymers and pulsed amperometry in flow injection analysis...
6091203 - Cerebral blood flow during conventional, new and open-chest cardio-pulmonary resuscitat...
Publication Detail:
Type:  Journal Article    
Journal Detail:
Title:  Critical care medicine     Volume:  38     ISSN:  1530-0293     ISO Abbreviation:  Crit. Care Med.     Publication Date:  2010 Jul 
Date Detail:
Created Date:  2010-06-21     Completed Date:  2010-07-22     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  0355501     Medline TA:  Crit Care Med     Country:  United States    
Other Details:
Languages:  eng     Pagination:  1542-7     Citation Subset:  AIM; IM    
Affiliation:
Department of Intensive Care, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands. L.Bisschops@ic.umcn.nl
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Carbon Dioxide / blood*
Cerebrovascular Circulation*
Coma / blood,  physiopathology*
Female
Heart Arrest / blood,  physiopathology*
Hemodynamics
Hospitals, University
Humans
Hypothermia, Induced*
Male
Middle Aged
Oxygen / blood*
Prospective Studies
Respiration, Artificial
Chemical
Reg. No./Substance:
124-38-9/Carbon Dioxide; 7782-44-7/Oxygen
Comments/Corrections
Comment In:
Crit Care Med. 2010 Jul;38(7):1603-5   [PMID:  20562547 ]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Protection against early intestinal compromise by lipid-rich enteral nutrition through cholecystokin...
Next Document:  Human immunodeficiency virus infection and hospital mortality in acute lung injury patients.