Hyperventilation in Patients With Traumatic Brain Injury

Effects of Moderate Hyperventilation on Cerebral Hemodynamics, Oxygenation and Metabolism in Patients With Severe Traumatic Brain Injury

Elevated intracranial pressure is a dangerous and potentially fatal complication after traumatic brain injury. Hyperventilation is a medical intervention to reduce elevated intracranial pressure by inducing cerebral vasoconstriction, which might be associated to cerebral ischemia and hypoxia.

The main hypothesis is that a moderate degree of hyperventilation is sufficient to reduce the intracranial pressure without inducing cerebral ischemia.

Study Overview

• Status: Completed
• Conditions: Hyperventilation; Head Injury Trauma
• Intervention / Treatment: Other: Hyperventilation test

Detailed Description

In patients with severe traumatic brain injury (TBI), and with intracranial pressure-monitoring, brain tissue oxygen tension and/or microdialysis probes hyperventilation-tests are performed in the acute phase after trauma. Data are collected and TCCD measurements are performed at baseline, at the beginning of moderate hyperventilation, after prolonged moderate hyperventilation (for 50 minutes) and after return to baseline.

The present study aims to quantify potential adverse effects of moderate short-term hyperventilation during the acute phase of the severe TBI on cerebral hemodynamics, oxygenation, and metabolism.

• Study Type: Interventional
• Enrollment (Actual): 11
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Switzerland
  • Zürich, Switzerland, 8006
    • University Hospital Zurich

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• nonpenetrating traumatic brain injury
• Glasgow coma scale <9 at presentation
• Intracranial pressure monitoring
• brain tissue oxygen tension monitoring and/or microdialysis monitoring
• invasive mechanical ventilation with FIO2 <60% and PEEP <15 mbar

Exclusion Criteria:

• decompressive craniectomy
• pregnancy
• pre-existing neurological disease
• previous traumatic brain injury
• acute cardiovascular disease
• severe respiratory failure
• acute on chronic liver disease
• sepsis
• failure to obtain satisfactory bilateral TCCD signals
• persisting hypovolemia or hemodynamic instability

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: patients with severe TBI; Patients with severe TBI enrolled in the study undergo an hyperventilation test, in which the alveolar ventilation is increased by a stepwise increase in tidal volumes and respiratory rate until a reduction of etCO2 of 0.7 kPa is achieved.	Other: Hyperventilation test; Increase of the alveolar ventilation by a stepwise increase in tidal volumes and respiratory rate until a reduction of end-tidal CO2 of 0.7 kPa is achieved

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
intracranial pressure	Change of intracranial pressure during moderate hyperventilation	10, 20, 50, 60 minutes after begin of the hyperventilation test

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
cerebral flow velocity in the middle cerebral artery	Change of cerebral flow velocity during moderate hyperventilation	20, 50, 60 minutes after begin of the hyperventilation test
brain tissue oxygenation (PbrO2)	no changes	10, 20, 50, 60 minutes after begin of the hyperventilation test
cerebral Lactate/ Pyruvate ratio	no changes	1 hour before initiation of the hyperventilation test, and 1 and 2 hours after begin of the hyperventilation test

Collaborators and Investigators

• Sponsor: University of Zurich
• Investigators: Principal Investigator: Peter Steiger, MD, University of Zurich

Publications and helpful links

General Publications

• Klinzing S, Stretti F, Pagnamenta A, Bechir M, Brandi G. Transcranial color-coded duplex sonography assessment of cerebrovascular reactivity to carbon dioxide: an interventional study. BMC Neurol. 2021 Aug 7;21(1):305. doi: 10.1186/s12883-021-02310-9.
• Brandi G, Stocchetti N, Pagnamenta A, Stretti F, Steiger P, Klinzing S. Cerebral metabolism is not affected by moderate hyperventilation in patients with traumatic brain injury. Crit Care. 2019 Feb 13;23(1):45. doi: 10.1186/s13054-018-2304-6.

Study record dates

Study Major Dates

• Study Start (Actual): May 20, 2014
• Primary Completion (Actual): May 2, 2017
• Study Completion (Actual): May 2, 2017

Study Registration Dates

• First Submitted: January 22, 2019
• First Submitted That Met QC Criteria: January 29, 2019
• First Posted (Actual): January 30, 2019

Study Record Updates

• Last Update Posted (Actual): January 30, 2019
• Last Update Submitted That Met QC Criteria: January 29, 2019
• Last Verified: January 1, 2019

More Information

Terms related to this study

• Keywords: intracranial pressure; cerebral oxygenation; cerebral metabolism
• Additional Relevant MeSH Terms: Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Respiratory Tract Diseases; Respiration Disorders; Trauma, Nervous System; Signs and Symptoms, Respiratory; Brain Injuries; Wounds and Injuries; Brain Injuries, Traumatic; Craniocerebral Trauma; Hyperventilation
• Other Study ID Numbers: KEK-ZH 2012-0542 (1)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No