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Diaphragmatic Tissue Doppler During Weaning From Mechanical Ventilation

Not Applicable
Completed
Conditions
Weaning From Mechanical Ventilation
Interventions
Other: Weaning TDI
Registration Number
NCT03962322
Lead Sponsor
Azienda Ospedaliero Universitaria Maggiore della Carita
Brief Summary

Weaning from mechanical ventilation is a critical issue and the diaphragmatic disfunction has been demonstrated to play an important role in extubation failure. the aim of present investigation is to evaluate diaphragmatic excursion velocity during in patients undergoing spontaneous breathing trial through tissue Doppler analysis in both inspiration and expiration.

Detailed Description

Tobin Index (RSBI), which is the ratio between respiratory rate (RR) and tidal volume (VT), is one of the most used indices to predict weaning outcome. The diaphragm plays a key role in generating VT and, in the case of diaphragmatic dysfunction, inspiratory accessory muscles may contribute to support ventilation. If this occurs during a spontaneous breathing trial (SBT), it will probably result in delayed weaning, since the accessory muscles are more fatigable than the diaphragm.

The diaphragmatic tissue Doppler imaging (TDI) is an ultrasonographic technique derived from ultrasound evaluation of heart's motility. Being a muscle doppler assessment, it can be easily used on the diaphragm to calculate the speed of muscles displacement that could be associated with patient's respiratory drive, as well as other derived index of muscle function.

The aim of the study is to measure the variations of diaphragmatic displacement velocities before and during the spontaneous breathing trial, useful to check if the patient is ready to breathe spontaneously. An observational study will be performed. Patients who are ready to be weaned will be subjected to a spontaneous breathing test (Cpap 5), that consists of applying a positive end-expiratory pressure of 5 cm H2O for 20 minutes. A tissue Doppler evaluation will then be performed by analyzing the diaphragmatic displacement velocity during inspiration and expiration in the modality of ventilation which precedes the trial and during the SBT.

Vital parameters will be monitored during the study. Mechanical ventilation length, incidence of tracheostomies, ICU and hospital recovery duration and hospital mortality will also be acquired.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
100
Inclusion Criteria
  • mechanical invasive ventilation ≥ 24 h
  • readiness for extubation
Exclusion Criteria
  • refusal to grant consent
  • pregnancy
  • hemodynamic instability
  • difficult management of secretions
  • request for inotropy and/or vasoactive drugs at high doses

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Weaning TDIWeaning TDIA tissue doppler evaluation, using a sector transducer, will be performed by analyzing the diaphragmatic displacement velocity during inspiration and expiration in the modality of ventilation which precedes the trial, during the SBT and after extubation.
Primary Outcome Measures
NameTimeMethod
Primary Outcome Measure - Change in diaphragmatic displacement velocitythrough each trial completion, an average of 20 minutes

Inspiratory and expiratory diaphragmatic displacement velocity evaluated with tissue doppler during the assisted ventilation modality which preceded the trial, during the spontaneous breathing trial ( CPAP 5 ) and in spontaneous breathing.

Secondary Outcome Measures
NameTimeMethod
Diaphragmatic acceleration and decelerationthrough each trial completion, an average of 20 minutes

Diaphragmatic acceleration and deceleration evaluated with tissue doppler during the assisted ventilation modality which preceded the trial, during the spontaneous breathing trial ( CPAP 5 ) and in spontaneous breathing.

Gas exchange - arterial carbon dioxide tensionthrough each trial completion, an average of 20 minutes

Arterial blood gases sample

Gas exchange - pHthrough each trial completion, an average of 20 minutes

Arterial blood gases sample

Gas exchange - arterial oxygen tensionthrough each trial completion, an average of 20 min

Arterial blood gases sample

Dyspnea levelthrough each trial completion, an average of 20 minutes

Dyspnea level will be evaluated through visual analogical scale ( VAS dyspnea). The dyspnea visual analog scale is represented by a 20 cm horizontal line. The ends are defined as the extreme limits of dyspnea from the left-lower end best, "not at all breathless"-to the right-upper end worst, "extremely breathless". Subjects will be instructed to indicate on the line the point corresponding to their breathlessness perception.

Heart ratethrough each trial completion, an average of 20 minutes

Heart Rate (HR) averages during each of the 3 ventilatory modes

Number of patients who experienced weaning failureover 48 hours following extubation

the need for non invasive ventilation or re-intubation due to any cause

Blood Pressurethrough each trial completion, an average of 20 minutes

Mean arterial Blood Pressure (BP) averages during each of the 3 ventilatory modes

Trial Locations

Locations (1)

A.O.U Maggiore della Carità

🇮🇹

Novara, Italy

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