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Published on: September 29, 2020
Handcrafted cuff manometers do not accurately measure endotracheal tube cuff pressure
Raquel Annoni1, Antonio Evanir de Almeida Junior1
1Departamento de Fisioterapia, Faculdade de Ciências Médicas de Pouso Alegre, Universidade do Vale do Sapucaí, Pouso Alegre, MG, BR.
Objective:
To test the agreement between two handcrafted devices and a cuff-specific manometer.
Methods:
The agreement between two handcrafted devices adapted to measure tracheal tube cuff pressure and a cuff-specific manometer was tested on 79 subjects. The cuff pressure was measured with a commercial manometer and with two handcrafted devices (HD) assembled with aneroid sphygmomanometers (HD1 and HD2). The data were compared using Wilcoxon and Spearman tests, the intraclass correlation coefficient (ICC) and limit-of-agreement analysis.
Results:
Cuff pressures assessed with handcrafted devices were significantly different from commercial device measurements (pressures were higher when measured with HD1 and lower with HD2). The ICCs between the commercial device and HD1 and HD2 were excellent (ICC = 0.8 p < 0.001) and good (ICC = 0.66, p < 0.001), respectively. However, the Bland- Altman plots showed wide limits of agreement between HD1 and HD2 and the commercial device.
Conclusion:
The handcrafted manometers do not provide accurate cuff pressure measurements when compared to a cuff-specific device and should not be used to replace the commercial cuff manometers in mechanically ventilated patients.
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