Cardiorespiratory Changes in Patients Being Weaned Off Mechanical Ventilation

Cardiorespiratory Changes in Patients Being Weaned Off Mechanical Ventilation: a Randomized Crossover Clinical Trial

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.

Study Overview

• Status: Completed
• Conditions: Critical Care; Weaning

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.

• Study Type: Observational
• Enrollment (Actual): 24

Contacts and Locations

Study Locations

• Brazil
  • RS
    • Porto Alegre, RS, Brazil
      • Federal University of Rio Grande do Sul

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• 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.

Description

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

Study Plan

How is the study designed?

Design Details

• Time Perspectives: Prospective

Collaborators and Investigators

• Sponsor: Hospital de Clinicas de Porto Alegre
• Investigators: Principal Investigator: Silvia RR Vieira, PhD, Hospital de Clinicas de Porto Alegre

Study record dates

Study Major Dates

• Study Start: December 1, 2005
• Primary Completion: December 7, 2022
• Study Completion (Actual): August 1, 2007

Study Registration Dates

• First Submitted: February 26, 2009
• First Submitted That Met QC Criteria: February 26, 2009
• First Posted (Estimate): February 27, 2009

Study Record Updates

• Last Update Posted (Estimate): February 27, 2009
• Last Update Submitted That Met QC Criteria: February 26, 2009
• Last Verified: February 1, 2009

More Information

Terms related to this study

• Keywords: diastolic dysfunction; weaning; Mechanical ventilation; echocardiogram
• Other Study ID Numbers: 2004341 UFRGS

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No