IRB-HSR# 14299: The Use of the Intrathoracic Pressure Regulator (ITPR) to Improve Cerebral Perfusion Pressure in Patients With Altered Intracranial Elastance

Summary

Patients who have a functioning intracranial pressure-monitoring device (either a subarachnoid bolt, or an intraventricular catheter) in place, and are either sedated, intubated, and mechanically ventilated (i.e. in the NNICU), or are scheduled to undergo an operation or interventional neuroradiological procedure at the University of Virginia. Patients with a contraindication to TTE will be excluded.

For patients in the NNICU, basic hemodynamic variables (systemic blood pressure, central venous pressure, etc.) will be collected. In addition, left ventricular performance (including estimates of LVEDV, LVESV, EF, FAC, and SV) will be assessed using TTE. Once these baseline data are recorded, the ITPR will be inserted in the ventilator circuit and activated to provide either -5 mm Hg or -9 mm Hg endotracheal rube pressure (ETP) (based on a randomization scheme). After the ITPR has been active for at least five minutes, the same intracranial, hemodynamic, and TTE data obtained above will be gathered. The ITPR will then be turned off for five minutes, and intracranial, hemodynamic, and TTE data will again be recorded. The ITPR will be activated a second time (-9 mm Hg or -5 mm Hg ETP, i.e. whichever value was not used previously), and after five minutes of use data will be recorded again. The ITPR will then be disconnected, data will be collected after waiting two minutes, and no further interventions will be made.

ABG's will be obtained before and during the use of the device at each setting.

This is a proof of concept/feasibility study designed to test the primary hypothesis that use of the ITPR will result in decreased intracranial pressure and increased cerebral perfusion pressure. The effect of the ITPR on secondary indicators of cardiac performance will also be examined. These include but are not limited estimates of ventricular end diastolic volume and pressure (LVEDV/P), ejection fraction (EF), left ventricular end systolic volume and pressure (LVESV/P), fractional area change (FAC), all of which will be assessed by transthoracic echocardiography (TTE) or transesophageal echocardiography (TEE).

Conditions

• Traumatic Brain Injury

Interventions

DEVICE

ITPR -5 mm Hg then -9 mm Hg

the ITPR will be inserted in the ventilator circuit and activated to provide either -5 mm Hg or -9 mm Hg endotracheal tube pressure (ETP) Each subject will have all measurements recorded at both -5 \& -9 mm Hg

DEVICE

ITPR -9 & then -5mm Hg

the ITPR will be inserted in the ventilator circuit and activated to provide either -5 mm Hg or -9 mm Hg endotracheal tube pressure (ETP) Each subject will have all measurements recorded at both -5 \& -9 mm Hg

Sponsors & Collaborators

• University of Virginia

  lead OTHER

Principal Investigators

• Edward C Nemergfut, MD · University of Virginia Anesthesiology

Study Design

Allocation

RANDOMIZED

Purpose

HEALTH_SERVICES_RESEARCH

Masking

DOUBLE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2009-05-31

Countries

• United States

Study Locations