Physiological Effects of Intrathoracic Pressure Regulation in Patients with Decreased Cerebral Perfusion Due to Brain Injury or Intracranial Pathology

Study ID
STU 042013-045

Cancer Related

Healthy Volunteers

Study Sites

Sonja Stutzman

Principal Investigator
Daiwai Olson


This is an observational evaluation in up to 20 patients to examine the effects of iTPR on cerebral physiology. The study group will receive initial treatment with a tidal volume setting of 6-8 ml/kg predicted body weight, and using the -12cm H2o iTPR. There is no randomization in this study, all patients admitted into the study receive the iTPR.
This research involves the use of the FDa approved CirQlator[RegisteredTM] device. The primary endpoint is the change from baseline CPP compared with the CPP during the use of iTPR. Secondary endpoints include the following:
1.Time to maximum increase in CPP during each iTPR treatment interval
2.Mean CPP during each iTPR treatment
3.Maximum CPP during each iTPR treatment
4.Change in CPP from the time iPR treatment is completed (assessed immediately prior to disconnecting the iTPR), and 15 minutes following removal of the iTPR
5.Change in Pbto2 or CBF during iTPR treatment compared to baseline and following removal of the iTPR; dependent on which advanced monitoring modality utilized
6.Change in SBP, DBP, MaP, HR, CVP (if available), PP, eTCo2, and Spo2; assessed at baseline, during iTPR treatment, and 15 minutes following removal of the iTPR
7.TCD snapshot before each change of intervention
8.optional: Change in lung compliance assessed at baseline, immediately following each iTPR treatment (e.g., prior to disconnecting the iTPR), and 15 minutes following removal of the iTPR a safety measure, arterial blood gases (aBGs, e.g., pH, po2, pCo2, base deficit, and HCo3) will be collected immediately following each study intervention (prior to disconnecting the iTPR). Change in aBGs will be evaluated as a secondary endpoint.
Patients will typically be recruited by referrals from healthcare professionals. The inclusion/exclusion criteria can be found on page 9 of the protocol.
once the patient (or LaR) has consented the following procedures will be conducted.
1.Collect baseline data prior to putting the iTPR in circuit (1 to 5 minutes prior to placement of iTPR).
2. 30 minutes of iTPR in circuit with no vacuum : attach the CirQLator device to the ventilation tube, ensure data are being collected and that monitors continue to read the patients necessary information, record necessary data (see below), instruct respiratory therapist to turn PeeP to 0, increase the Tidal Volume by 50 ml, and adjust the ventilatory settings to achieve normocarbia.
3. 120 minutes of iTPR in circuit: vacuum on (see below for data points to be collected)
4. 30 minutes iTPR in circuit vacuum off: turn vacuum off (see below)
Data to be recorded: heart rate, MaP, systolic and diastolic BP, iCP, CPP, Pbto2, Spo2, eTCo2, Fio2, HR, TV, (inspired and expired), VCo2, eTCo2, RR, PiP, niP,aBG, TCD, BMP.
5. Remove iTPR from patient circuit and take one last ready of data listed above.

Participant Eligibility

1. Patient is greater than or equal to 18 years of age
2. Patient is intubated and mechanically ventilated and may tolerate a volume controlled mode
3. Patient has a head injury or other intracranial pathology, with a functioning intracranial pressure monitor at time of study, and compromised cerebral perfusion per the attending physician for at least 30 minutes at any point within the past 24 hours prior to enrollment
4. Patient has an arterial line in place or an alternative pressure measuring device (cuff) with continuous arterial pressure monitoring
5.Patient has SpO2>= 90% (by pulse oximetry), with PEEP requirement of no more than 7cm H20 immediately prior to initiation of study IPR treatment
6.Patient is hemodynamically stable, defined as sustained MAP > 55, with or without the requirement for vasopressors
7.Patient is in the ICU OR is about to undergo neurosurgery with current or planned placement of an invasive ICP monitor
8.Inclusion in the study presents no significant delays to planned emergent neurosurgery, if applicable
9.Prior written informed consent has been provided