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Trial registered on ANZCTR


Registration number
ACTRN12610000756022
Ethics application status
Approved
Date submitted
13/08/2010
Date registered
14/09/2010
Date last updated
14/09/2010
Type of registration
Retrospectively registered

Titles & IDs
Public title
Comparison of rapid shallow breathing index (RSBI) calculated under direct and indirect form in the postoperative period of cardiac surgery
Scientific title
Comparison of rapid shallow breathing index (RSBI) calculated under direct and indirect form in the postoperative period of cardiac surgery
Secondary ID [1] 252439 0
no
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
myocardial revascularization 243533 0
Extubation after cardiac surgery 257957 0
Condition category
Condition code
Cardiovascular 239833 239833 0 0
Coronary heart disease
Surgery 258126 258126 0 0
Other surgery

Intervention/exposure
Study type
Observational
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Twenty two adult patients (17 males and 5 females) in the postoperative period of cardiac surgery and in mechanical ventilation were studied. Before data collection, each patient was evaluated, received physiotherapy care and was positioned in elevated dorsal recumbent at forty-five degrees. After these procedures, minute ventilation (MV) and respiratory rate (RR) obtained from mechanical ventilator display and digital respirometer ( for one minute)were recorded. The RSBI was calculated by the ratio of RR and tidal volume (VT). Paired t-test to compare related variables (RR, VT). The intra-class correlation coefficients (ICCs) were determined.
Intervention code [1] 241142 0
Not applicable
Comparator / control treatment
Comparison of RSBI as calculated from the mechanical ventilator display is compared to the RSBI as calculated from the digital respirometer.
Control group
Active

Outcomes
Primary outcome [1] 240599 0
A significant difference was found between the RSBI obtained from the ventilator and by the digital respirometer (p=0.011). The two methods exhibited high interrelation. There was a close correlation between RSBI (ICC=0.86), a moderate concordance related to MV (ICC=0.74) and high concordance related to RR (ICC=0.8) and VT (ICC=0.79) were observed. To all variables the p-value was < 0.05.
Timepoint [1] 240599 0
The RSBI assessed in each patient during one session only. Statistical analysis undertaken on completion of all data collection.
Secondary outcome [1] 257227 0
nil
Timepoint [1] 257227 0
nil

Eligibility
Key inclusion criteria
Patients in the immediate postoperative period of elective cardiac surgery, over 18 years who had previously signed the consentiment term free and clear in intubation and mechanical ventilation.
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Hemodynamically unstable patients on inotropic support; Glasgow Coma Scale less than 8 points, using mechanical ventilation on a respirator machine different from Hamilton Raphael; postoperative emergency surgery.

Study design
Purpose
Natural history
Duration
Longitudinal
Selection
Defined population
Timing
Prospective
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 1957 0
Brazil
State/province [1] 1957 0

Funding & Sponsors
Funding source category [1] 257458 0
University
Name [1] 257458 0
State University of Campinas
Address [1] 257458 0
Roxo Moreira Street, Zip code 13081-970, Cidade Universitaria, Campinas Sao Paulo
Country [1] 257458 0
Brazil
Funding source category [2] 257556 0
Hospital
Name [2] 257556 0
Clinical Hospital State University of Campinas
Address [2] 257556 0
Vital Brasil, street, 251, Zip code: 13083-888
Cidade Universitaria, Campinas, Sao Paulo
Country [2] 257556 0
Brazil
Funding source category [3] 257557 0
Hospital
Name [3] 257557 0
clinical hospital State University of Campinas
Address [3] 257557 0
Vital Brasil street, 251
Cidade Universitaria
Zeferino Vaz
Campinas - SP
Zip code -13083-888
Country [3] 257557 0
Brazil
Primary sponsor type
Individual
Name
Fernando Augusto Martins Lessa
Address
Conego Manoel Garcia street, number 98, apartment number 41, Campinas, Sao Paulo, Zip code 13070036
Country
Brazil
Secondary sponsor category [1] 256778 0
University
Name [1] 256778 0
State University of Campinas
Address [1] 256778 0
Zeferino Vaz street Barao Geraldo district Zip code 13081-970 - Campinas
Country [1] 256778 0
Brazil
Other collaborator category [1] 251439 0
Individual
Name [1] 251439 0
Sebastiao Araujo
Address [1] 251439 0
Padre Almeida street, number 451, apartment 12, Campinas, Sao Paulo, Zip code 13025251
Country [1] 251439 0
Brazil

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 259481 0
Research Ethics Committee of State University of Campinas
Ethics committee address [1] 259481 0
Tessalia Vieira de Camargo street, number 126, Zip code: 13083887
Ethics committee country [1] 259481 0
Brazil
Date submitted for ethics approval [1] 259481 0
07/07/2008
Approval date [1] 259481 0
22/07/2008
Ethics approval number [1] 259481 0
526/2008

Summary
Brief summary
Objectives: To compare and analyze whether the values of rapid shallow breathing index (RSBI) determined by means of a ventilator display and a digital respirometer were correlated. Methods: Twenty two adult patients (17 males and 5 females) in the postoperative period of cardiac surgery and in mechanical ventilation were studied. Before data collection, each patient was evaluated, received physiotherapy, in order to promote hygiene bronchial and pulmonary reexpansion, care and was positioned in elevated dorsal recumbent at forty-five degrees. After these procedures, minute ventilation (MV) and respiratory rate (RR) obtained from mechanical ventilator display and digital respirometer were recorded. The RSBI was calculated by the ratio of RR and tidal volume (VT). Paired t-test to compare related variables. The intra-class correlation coefficients (ICCs) were determined. Results: A significant difference was found between the RSBI obtained from the ventilator and by the digital respirometer (p=0.011). The two methods exhibited high interrelation. There was a close correlation between RSBI (ICC=0.86), a moderate concordance related to MV (ICC=0.74) and high concordance related to RR (ICC=0.8) and VT (ICC=0.79) were observed. To all variables the p-value was <0.05. Conclusions: There were a significant concordance between the RSBI obtained from the ventilator display and the digital respirometer. However, the sample was small and more studies are needed to establish a model of correction of obtained values, as long as many authors have reported that pressure support ventilation can overestimate the RSBI.
Key words: ventilator weaning, mechanical ventilation, rapid shallow breathing index, respiratory therapists cardiac surgical procedures
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 30063 0
Address 30063 0
Country 30063 0
Phone 30063 0
Fax 30063 0
Email 30063 0
Contact person for public queries
Name 13310 0
Fernando Augusto Martins Lessa
Address 13310 0
Conego Manuel Garcia street, 98, Campinas, Sao Paulo, Zip code 13070036
Country 13310 0
Brazil
Phone 13310 0
55 19 41415480
Fax 13310 0
Email 13310 0
lessa.fernando@gmail.com
Contact person for scientific queries
Name 4238 0
Rodrigo Marques Tonella
Address 4238 0
Culto a Ciencia street, 257, Campinas, Sao Paulo, Zip code 13020060
Country 4238 0
Brazil
Phone 4238 0
55 19 91562113
Fax 4238 0
Email 4238 0
digomato@terra.com.br

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary