We updated the design of this site on December 18, 2017. Learn more.
ClinicalTrials.gov Menu

Hypercapnia to Prevent Secondary Ischemia in SAH (SAHCO2)

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
ClinicalTrials.gov Identifier: NCT01799525
Recruitment Status : Completed
First Posted : February 26, 2013
Last Update Posted : December 10, 2014
Information provided by (Responsible Party):

Study Description
Brief Summary:
Delayed cerebral vasospasm and secondary ischemic infarction are feared complications after aneurysmal subarachnoid hemorrhage (aSAH). To date, there is no effective therapy to prevent these ischemic complications. The arterial partial pressure of carbon dioxide (PaCO2) is one of the main determinants of cerebral blood flow (CBF) in healthy subjects. It is yet largely unknown, if and to what extent modulations of PaCO2 can influence CBF in patients after aSAH. The trial is a phase 1 study in which the feasibility of hypercapnia in SAH patients is tested. PaCO2 is gradually raised to 60 mmHg in 10 mechanically ventilated aSAH patients. Cerebral oxygen saturation measured by NIRS and CBF determined by an intracerebral thermodilution probe are the primary end points. If the feasibility is confirmed, this trial will be followed by a phase 2 dose finding study.

Condition or disease Intervention/treatment Phase
Aneurysmal Subarachnoid Hemorrhage Procedure: Hypercapnia by reduction of respiratory volume Phase 1

Detailed Description:
The course of aneurysmal subarachnoid hemorrhage (aSAH) is determined by the sequence of several ischemic episodes. Immediately after aSAH, an increase of ICP causes an increase of CBF. It is followed by an acute vasoconstriction over the next hours and days. Typically between day 4 and 10 after aSAH, delayed arterial narrowing and a decrease of CBF occurs in approximately 50 % of aSAH patients and may result in cerebral ischemia and infarction. After the failure of the CONSCIOUS-trial to improve outcome after aSAH, there is no specific treatment in sight to effectively prevent cerebral ischemic events after aSAH. Under physiological conditions, the arterial partial pressure of carbon dioxide (PaCO2) is one of the main determinants of cerebral blood flow (CBF). An elevation of PaCO2 may also be a useful treatment on aSAH patients. This trial is designed as a phase 1 study to test the feasibility of controlled hypercapnia in mechanically ventilated aSAH patients with poor-grade SAH. Monitoring is performed by an external ventricular drainage (ICP), near infrared spectroscopy (tissue oxygenation) and a thermodilution probe (CBF). The latter monitoring tools represent the primary end points of this study. In case of affirmed feasibility, a dose finding study will be launched as a next step.

Study Design

Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 10 participants
Intervention Model: Single Group Assignment
Masking: Single (Participant)
Primary Purpose: Treatment
Official Title: Therapeutical Hypercapnia to Prevent Secondary Ischemic Events in Aneurysmal Subarachnoid Hemorrhage (aSAH)
Study Start Date : January 2013
Primary Completion Date : February 2014
Study Completion Date : August 2014

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Bleeding
U.S. FDA Resources

Arms and Interventions

Arm Intervention/treatment
Experimental: Hypercapnia
Intervention: SAH patients are subjected to gradual hypercapnia by reduction of respiratory volume in one trial session every day. PaCO2 is raised from normocapnia to 50 mmHg for 10 - 15 minutes and 60 mmHg for 10 - 15 minutes.
Procedure: Hypercapnia by reduction of respiratory volume
By reduction of the respiratory volume, PaCO2 is raised while paO2 is kept constant by modulation of the oxygen supply through the respirator,

Outcome Measures

Primary Outcome Measures :
  1. Cerebral Blood Flow [ Time Frame: For an average of two weeks after aSAH ]
    Between day 4 and 14, PaCO2 is gradually raised from normocapnic values (40 mmHg) to hypercapnic values (50 and 60 mmHg). CBF is continuously measured during this intervention. Patients are clinically and radiologically followed for 6 months.

Secondary Outcome Measures :
  1. Cerebral oxygen saturation [ Time Frame: For an average of two weeks after aSAH ]
    Oxygen saturation by NIRS is measured continuously for 2 weeks after aSAH.

  2. intracranial pressure (ICP) [ Time Frame: For an average of two weeks ]
    ICP is continuously measured by an external ventricular drainage throughout the intervention period.

Eligibility Criteria

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • aneurysmal SAH
  • SAH Hunt/Hess Grade 3-5
  • SAH Fisher Grade 2-4
  • Mechanically ventilated
  • external ventricular drainage/ICP measurement

Exclusion Criteria:

  • Age under 18
  • ICP > 25 mmHg for > 2 minutes
  • pH < 7.250
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT01799525

Department of Neurosurgery, University of Wuerzburg
Wuerzburg, Bavaria, Germany, 97080
Sponsors and Collaborators
Wuerzburg University Hospital
Principal Investigator: Thomas Westermaier, MD Department of Neurosurgery, University of Wuerzburg, Germany
Study Director: Ekkehard Kunze, MD Department of Neurosurgery, University of Wuerzburg
More Information

Publications automatically indexed to this study by ClinicalTrials.gov Identifier (NCT Number):
Responsible Party: Dr. Thomas Westermaier, MD, Wuerzburg University Hospital
ClinicalTrials.gov Identifier: NCT01799525     History of Changes
Other Study ID Numbers: WUE102/12
First Posted: February 26, 2013    Key Record Dates
Last Update Posted: December 10, 2014
Last Verified: December 2014

Keywords provided by Dr. Thomas Westermaier, Wuerzburg University Hospital:
subarachnoid hemorrhage
cerebral ischemia

Additional relevant MeSH terms:
Subarachnoid Hemorrhage
Pathologic Processes
Intracranial Hemorrhages
Cerebrovascular Disorders
Brain Diseases
Central Nervous System Diseases
Nervous System Diseases
Vascular Diseases
Cardiovascular Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms