Cardiorespiratory Changes in Patients Being Weaned Off Mechanical Ventilation

This study has been completed.
Information provided by:
Hospital de Clinicas de Porto Alegre Identifier:
First received: February 26, 2009
Last updated: NA
Last verified: February 2009
History: No changes posted
The objective of this study was to analyze changes in cardiac function using Doppler echocardiogram in critical patients during weaning from mechanical ventilation using two different weaning methods (pressure support and T-tube) and to compare a subgroup of patients: success vs. failure in weaning and patients with vs. without heart disease.

Critical Care

Study Type: Observational
Study Design: Time Perspective: Prospective
Official Title: Cardiorespiratory Changes in Patients Being Weaned Off Mechanical Ventilation: a Randomized Crossover Clinical Trial

Further study details as provided by Hospital de Clinicas de Porto Alegre:

Enrollment: 24
Study Start Date: December 2005
Study Completion Date: August 2007
Detailed Description:

Weaning from mechanical ventilation (MV) involves physiological changes that can overload the cardiorespiratory system due to changes in the interaction between patient and ventilator.

This was a randomized crossover clinical trial that included patients in an intensive care unit (ICU) who had been on MV for more than 48 hours and who were considered ready for weaning. Cardiorespiratory variables, oxygenation, electrocardiogram (ECG) and Doppler echocardiogram findings were analyzed at baseline and after 30 minutes in each trial weaning method (PSV and T-tube). Comparisons were made between PSV and T-tube, weaning success and failure and patients with and without heart disease, using ANOVA and Student's t test. The level of significance was set at p < 0.05.


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population
Patients receiving MV for more than 48 hours, who had been admitted to the Intensive Care Unit (ICU), and who met the criteria for weaning from MV according to the parameters previously defined were selected to participate in this study.

Inclusion Criteria:

  • patients hemodynamically stable
  • conscious (Glasgow scale ≥ 13)
  • with adequate gaseous exchange (O2 saturation ≥ 95%, fraction of inspired oxygen (FiO2) ≤ 40% and positive end-expiratory pressure (PEEP) = 5
  • with no acidosis or alkalosis)
  • normal electrolyte levels
  • presence of respiratory drive
  • informed consent was signed by the patients and/or family members

Exclusion Criteria:

  • hemodynamic instability
  • severe intracranial disease
  • barotrauma
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Please refer to this study by its identifier: NCT00852891

Federal University of Rio Grande do Sul
Porto Alegre, RS, Brazil
Sponsors and Collaborators
Hospital de Clinicas de Porto Alegre
Principal Investigator: Silvia RR Vieira, PhD Hospital de Clínicas de Porto Alegre
  More Information

No publications provided

Responsible Party: Silvia Regina Rios Vieira, Hospital de Clínicas de Porto Alegre Identifier: NCT00852891     History of Changes
Other Study ID Numbers: 2004341 UFRGS
Study First Received: February 26, 2009
Last Updated: February 26, 2009
Health Authority: Brazil: National Committee of Ethics in Research

Keywords provided by Hospital de Clinicas de Porto Alegre:
diastolic dysfunction
Mechanical ventilation processed this record on November 27, 2015