Hypercapnia to Prevent Secondary Ischemia in SAH
Keywords
Abstract
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.
Dates
| Last Verified: | 11/30/2014 |
| First Submitted: | 02/19/2013 |
| Estimated Enrollment Submitted: | 02/22/2013 |
| First Posted: | 02/25/2013 |
| Last Update Submitted: | 12/08/2014 |
| Last Update Posted: | 12/09/2014 |
| Actual Study Start Date: | 12/31/2012 |
| Estimated Primary Completion Date: | 01/31/2014 |
| Estimated Study Completion Date: | 07/31/2014 |
Condition or disease
Intervention/treatment
Procedure: Hypercapnia
Phase
Arm Groups
| 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 the respiratory volume, PaCO2 is raised while paO2 is kept constant by modulation of the oxygen supply through the respirator, |
Eligibility Criteria
| Ages Eligible for Study | 18 Years To 18 Years |
| Sexes Eligible for Study | All |
| Accepts Healthy Volunteers | Yes |
| Criteria | 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 |
Outcome
Primary Outcome Measures
1. Cerebral Blood Flow [For an average of two weeks after aSAH]
Secondary Outcome Measures
1. Cerebral oxygen saturation [For an average of two weeks after aSAH]
2. intracranial pressure (ICP) [For an average of two weeks]
