Effects of Inspiration Rise Time on Work of Breathing and Comfort of Conscious Patients on Mechanical Ventilation

This study has been completed.
Sponsor:
Information provided by:
Radboud University
ClinicalTrials.gov Identifier:
NCT00294879
First received: February 21, 2006
Last updated: May 30, 2008
Last verified: May 2008
  Purpose

Introduction Pressure Support Ventilation is widely used in patients in the ICU. Matching the patient's respiratory needs with adequate ventilator settings is necessary to ensure a low work of breathing (WOB) and maximal patient comfort. The inspiratory rise time (IRT) determines the time to reach the selected airway pressure. A short IRT results in a high peak inspiratory flow and a short time to reach that peak, but is also associated with the development of turbulent flow, resulting in increased WOB. Aim of this study is to investigate the effects of different IRT settings on WOB and patient comfort during pressure support ventilation.

Methods We will performed a prospective, single blind cohort study in patients on Pressure Support Ventilation. 10 healthy adult patients admitted to the ICU after elective facial or neck surgery will be included. All patients will be ventilated in pressure support mode using a Servo 300 ventilator (Siemens. Elema, Solna, Sweden), with a positive end expiratory pressure of 5 cm H2O, pressure support level of 12 cm H2O above PEEP and an inspiratory oxygen fraction of 0.40. Patients have to be awake and cooperative (Ramsay 2). WOB will be measured with an esophageal balloon, and miniature flowmeter (Bicore system). Breathing comfort will be evaluated using a visual analogue scale (VAS) ranging from 1 to 10. WOB and patient comfort will be measured (in random order) at 0, 5, and 10% IRT. For statistical analysis the two-way analysis of variance will used. A p value of < 0.05 will be considered statistically significant.


Condition Intervention
Mechanical Ventilation
Procedure: pressure support ventilation at 0, 5, and 10% IRT

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single Blind

Further study details as provided by Radboud University:

Primary Outcome Measures:
  • Work of breathing

Secondary Outcome Measures:
  • patient comfort

Estimated Enrollment: 10
Study Start Date: February 2006
Study Completion Date: March 2008
Detailed Description:

Introduction Pressure Support Ventilation is widely used in patients in the ICU. Matching the patient's respiratory needs with adequate ventilator settings is necessary to ensure a low work of breathing (WOB) and maximal patient comfort. The inspiratory rise time (IRT) determines the time to reach the selected airway pressure. A short IRT results in a high peak inspiratory flow and a short time to reach that peak, but is also associated with the development of turbulent flow, resulting in increased WOB. Aim of this study is to investigate the effects of different IRT settings on WOB and patient comfort during pressure support ventilation.

Methods We will performed a prospective, single blind cohort study in patients on Pressure Support Ventilation. 10 healthy adult patients admitted to the ICU after elective facial or neck surgery will be included. All patients will be ventilated in pressure support mode using a Servo 300 ventilator (Siemens. Elema, Solna, Sweden), with a positive end expiratory pressure of 5 cm H2O, pressure support level of 12 cm H2O above PEEP and an inspiratory oxygen fraction of 0.40. Patients have to be awake and cooperative (Ramsay 2). WOB will be measured with an esophageal balloon, and miniature flowmeter (Bicore system). Breathing comfort will be evaluated using a visual analogue scale (VAS) ranging from 1 to 10. WOB and patient comfort will be measured (in random order) at 0, 5, and 10% IRT. For statistical analysis the two-way analysis of variance will used. A p value of < 0.05 will be considered statistically significant.

  Eligibility

Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • awake and cooperative patient
  • ICU admission following surgery of head or neck

Exclusion Criteria:

  • coagulopathy
  • inability to sit
  • hypoxemia and/or hypercapnia and /or hypocapnia
  • Pain score > 5 (on scale 1-10)
  • esophageal abnormalities
  • Pregnancy
  • COPD
  Contacts and Locations
Please refer to this study by its ClinicalTrials.gov identifier: NCT00294879

Locations
Netherlands
Radboud University Nijmegen Medical Centre
Nijmegen, Netherlands, 6500 HB
Sponsors and Collaborators
Radboud University
Investigators
Principal Investigator: Cornelia WE Hoedemaekers, MD PhD Radboud University
  More Information

No publications provided

Responsible Party: Radboud University Nijmegen Medical Centre
ClinicalTrials.gov Identifier: NCT00294879     History of Changes
Other Study ID Numbers: LBCH 0601
Study First Received: February 21, 2006
Last Updated: May 30, 2008
Health Authority: Netherlands: The Central Committee on Research Involving Human Subjects (CCMO)

ClinicalTrials.gov processed this record on April 16, 2014