The Distribution of Pressure in the Thorax During Mechanical Ventilation and Its Effects on the Circulation

NCT01113073 | Unknown DMC

• 1 other identifier: UMCN_IC_BL_01/2010
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Fluid administration is a daily intervention on the intensive care unit to improve cardiac output (CO) and stabilize circulation in critically ill patients. Simultaneously, the volume status of the patient is very difficult to assess. Too little volume leads to inadequate organ perfusion followed by ischemia and organ failure. Too much volume may worsen heart failure and cause pulmonary and peripheral edema and contribute to further tissue injury and organ dysfunction. Although dynamic indices have been shown to be more accurate predictors of fluid responsiveness, this relevant and complex task is usually guided by static clinical variables and the specialist's interpretation due to the fact that the interpretation of dynamic parameters is not fully developed and that they are not universally available. This lack of understanding is partially because of the complex interaction with mechanical ventilation. The investigators hypothesize that knowing the distribution of ventilatory pressures will make it possible to index dynamic parameters to tidal volume and improve their predictive value concerning the volume status of the patient. In addition, it would be of interest to be able to predict fluid responsiveness in a non-invasive way, especially in critically ill patients. Up to now, continuous non-invasive cardiac output monitoring using Nexfin in critically ill patients has not been validated and also not tested for its ability to predict fluid responsiveness. The present research proposal evaluates the possibility and accuracy of the model flow analysis obtained by non-invasive finger arterial pressure measurements to determine fluid responsiveness using passive leg raising. It will also be compared to a more invasive method (that is currently used in the clinic) to assess its ability to measure absolute CO levels accurately. It may make it possible to assess fluid responsiveness in a non-invasive and patient friendly way.

Conditions

Fluid Responsiveness

Keywords

pulse pressure variation; hemodynamic monitoring; fluid responsiveness; mechanical ventilation; fluid therapy

Outcome Measures

Primary Outcomes (1)

• fluid responsiveness

  pulse pressure variation (PPV), systolic pressure variation (SPV), stroke volume variation (SVV), pre-ejection period variation (dPEP)

  30 minutes around fluid challenge

Secondary Outcomes (4)

• Pressure distribution in thorax due to mechanical ventilation

  30 minutes of varying tidal volumes

• Dynamic indices in pressure support ventilation

  30 minutes of pressure support

• non invasive prediction of fluid responsiveness

  30 minutes around fluid challenge

• pressure distribution and dynamic indices during spontaneous breathing

  5 minutes of spontaneous breathing

Study Arms (1)

Elective open heart surgery

EXPERIMENTAL

Patients who had undergone elective open heart surgery

Other: ventilatory protocol; Other: Elastic band; Other: passive leg raising test

Interventions

ventilatory protocol OTHER

Ventilatory protocol for short period with four different tidal volumes (12 min)

Elective open heart surgery

Elastic band OTHER

Placement of an elastic band around thorax to reduce thorax compliance

Elective open heart surgery

passive leg raising test OTHER

performing the passive leg raising test

Elective open heart surgery

Eligibility Criteria

• Sex: all
• Healthy Volunteers: No
• Age Groups: Child (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

• Elective open heart surgery.

You may not qualify if:

• Significant cardiac arrhythmias, including atrial fibrillation.
• Hemodynamical instability, as defined by a variation in heart rate, blood pressure and cardiac output of more than 10% during the 15-min period before starting the protocol.
• Recent myocardial infarction (\< 3 mnd, troponine \> 50 ug/l).

Sponsors & Collaborators

• Radboud University Medical Center: lead

Study Sites (1)

Radboud University Nijmegen Medical Centre

Nijmegen, Netherlands

RECRUITING

Study Officials

• Benno Lansdorp, MSc.

  Radboud University Medical Center

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Peter Pickkers, MD, PhD

CONTACT

p.pickkers@ic.umcn.nl

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: DIAGNOSTIC
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER

Study Record Dates

• First Submitted: April 22, 2010
• First Posted: April 29, 2010
• Study Start: January 1, 2010
• Primary Completion: September 1, 2010
• Study Completion: September 1, 2010
• Last Updated: August 31, 2010

Record last verified: 2010-01

Locations

NL (1)