Heart Rate Variability During Weaning From Mechanical Ventilation

Critical Care Clinical Trial

Official title:

The Effect of T-Tube and Pressure Support on Cardiorespiratory Variables and Heart Rate Variability During Weaning From Mechanical Ventilation

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT00851825
• Other study ID #: 03-435
• Status: Completed
• Phase: N/A
• First received: February 25, 2009
• Last updated: May 7, 2009
• Start date: March 2003
• Est. completion date: June 2007

Study information

• Verified date: May 2009
• Source: Hospital de Clinicas de Porto Alegre
• Contact: n/a
• Is FDA regulated: No
• Health authority: Brazil: National Committee of Ethics in Research
• Study type: Observational

Clinical Trial Summary

The discontinuation of mechanical ventilation (MV) and the recovery of spontaneous breathing can lead to important cardiovascular alterations due to changes in the intrathoracic pressure. The autonomic modulation assessed through heart rate variability (HRV) during weaning from MV and its impact on cardiorespiratory variables has not been well elucidated yet. To evaluate the effect of T-tube (TT) and pressure support ventilation (PSV) during weaning from MV on cardiorespiratory variables and heart rate variability.

Description:

Thirty patients who had received MV for ≥ 48 hours and who met the criteria for weaning were assessed. Two different weaning methods were used and randomization was performed to choose one of the following sequences (baseline, PSV, rest, TT; or baseline, TT, rest, PSV). HRV was assessed by heart rate spectral analysis during MV, PSV, and TT. Each intervention lasted 30 minutes and there was a 30-minute rest period between the interventions. At the end of each period of time, the following cardiorespiratory variables were analyzed: respiratory rate (f), minute ventilation (VE), tidal volume (VT), rapid shallow breathing index (f/VT), peripheral oxygen saturation (SpO2), heart rate (HR) and blood pressure. In the HRV, the total spectral power (TP), the low frequency (LF) and the high frequency (HF) components, and the ratio between the low/high frequency (LF/HF) components were calculated.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 30
• Est. completion date: June 2007
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Patients with respiratory failure receiving MV for more than 48 hours

• for weaning from MV according to the parameters previously defined were selected to participate in this study

Exclusion Criteria:

• arterial hypotension (systolic blood pressure < 100mmHg), severe brain disease, barotraumas, presence of thoracic drain or tracheostomy, using vasoactive and sedative drugs

Study Design

Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Critical Care
• Weaning

Locations

Country	Name	City	State
Brazil	Federal University of Rio Grande do Sul	Porto Alegre	RS

Sponsors (1)

Lead Sponsor	Collaborator
Hospital de Clinicas de Porto Alegre

Country where clinical trial is conducted

Brazil, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	heart rate variability analysis		minutes	Yes
Secondary	Cardiorespiratory variables		minutes	Yes