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Respiratory Mechanics and Patient-ventilator Asynchrony Index in Patients With Invasive Mechanical Ventilation

Completed
Conditions
Respiratory Insufficiency
Interventions
Other: mechanical ventilation
Registration Number
NCT02687802
Lead Sponsor
University of Sao Paulo General Hospital
Brief Summary

The objective of the study is to estimate the incidence of asynchrony and to assess its relationship with respiratory mechanics. This will be a prospective cohort study, including patients under invasive mechanical ventilation. Within 48h post intubation, the investigators will record the values of intrinsic positive end-expiratory pressure, pulmonary compliance and resistance. Participants will be followed up from intubation to mechanical ventilation liberation. The investigators will register clinical signs of asynchrony and record ventilator waveforms continuously and quantify patient-ventilator asynchrony. The investigators will calculate the total asynchrony index (AI) and of each asynchrony type (ineffective triggering, double triggering, auto triggering, short cycling and prolonged cycling). Participants will be followed up until hospital discharge.

Detailed Description

Patient-ventilator asynchrony is common in patients under invasive mechanical ventilation, present between 10 and 80% of all respiratory cycles, and is associated with adverse clinical outcomes, such as delay in the weaning process, increased complications of mechanical ventilation, with possible impact on survival. The objective of this study is to estimate the incidence of asynchrony and to assess its relationship with respiratory mechanics. This will be a prospective cohort study, including all patients under invasive mechanical ventilation admitted at Respiratory ICU at Hospital das Clínicas da Faculdade de Medicina da Universidade de Sao Paulo (USP), during the study period. Within 48h post intubation, the investigators will record the values of intrinsic positive end-expiratory pressure, pulmonary compliance and resistance. Participants will be followed up from intubation to mechanical ventilation liberation. The investigators will register clinical signs of asynchrony and record ventilator waveforms continuously. The ventilator waveforms will be captured directly from ventilator and processed by dedicated software, without direct contact with patients. Later, ventilator waveforms will be analyzed to quantify patient-ventilator asynchrony. The investigators will calculate the total asynchrony index (AI) and of each asynchrony type (ineffective triggering, double triggering, auto triggering, short cycling and prolonged cycling). Participants will be followed up until hospital discharge, and the investigators will record duration of mechanical ventilation, the use of non-invasive ventilation post-extubation, reintubation, tracheostomy, ICU and hospital length of stay and survival. With this project, the investigators will estimate the incidence and magnitude of patient-ventilator asynchrony and its association with clinical outcomes

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
103
Inclusion Criteria
  • Recent mechanical ventilation (less than 72 hours)
  • Expectation of mechanical ventilation for more than 24 hours
  • Age ≥ 18 years old
Exclusion Criteria
  • High flow Bronchopleural fistula
  • Thoracic or abdominal deformities that could compromise the accuracy of respiratory mechanics measurement
  • Impossibility to measure respiratory mechanics
  • Tracheostomy

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Mechanical ventilationmechanical ventilationPatients under mechanical ventilation for more than 24h
Primary Outcome Measures
NameTimeMethod
asynchrony indexfrom study inclusion until the date of extubation or date of death from any cause, whichever comes first, up to 28 days

asynchrony index will be calculated as the number of major asynchrony events divided by total number of respiratory cycles

Secondary Outcome Measures
NameTimeMethod
ventilation free-days28 days

number of days alive and off the ventilator up to day 28

Clinical signs of patient-ventilator asynchronydaily, from study inclusion until the date of extubation or date of death from any cause, whichever comes first, up to 28 days

a standardized questionnaire will be used to evaluate the presence of clinically significant patient-ventilator asynchrony. Trained investigators will observe participant´s breathing pattern and other clinical signs of patient-ventilator asynchrony and score each item as absent (0) or present (1). Then, they will visual inspection of ventilator waveforms on the ventilator screen for a 5 minute observation period, looking for missed efforts, double triggering, auto-triggering, cycling delay and premature cycling, as previously defined. If they observe more than 1 asynchrony event for every 10 respiratory cycles, they will rate this item as present (1), otherwise, they will rate it as absent (0).

tracheostomy rateup to 90 days

performance of surgical or bronchoscopy-guided tracheotomy

Survival rateat 28 and 90 days

survival from intubation up to 90 days

Trial Locations

Locations (1)

Hospital das Clínicas -HCFMUSP

🇧🇷

Sao Paulo, SP, Brazil

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