Precision and accuracy of oxygen flow meters used at hospital settings.
Respir Care
; 57(7): 1071-5, 2012 Jul.
Article
em En
| MEDLINE
| ID: mdl-22273474
ABSTRACT
BACKGROUND:
Oxygen therapy is an important therapeutic resource for patients with hypoxemia. When changing oxygen flow meters, we have observed that sometimes, even with the same oxygen flow setting as before, a different S(pO(2)) is obtained.OBJECTIVE:
To analyze the precision and accuracy of flow meters used in hospital settings.METHODS:
An experimental study was performed to test oxygen flow meters from a tertiary hospital, by using a calibrated flow analyzer. Used and new flow meter accuracy was tested by reading in the gas analyzer a single measurement at flow rates of 1, 3, 5, and 10 L/min in 91 flow meters, and they were compared using the Student t test or Mann-Whitney U test. Flow meter precision was tested by reading in the flow analyzer 3 repetitive measurements set at flow rates of 1, 3, 5, and 10 L/min in 11 flow meters, and the reproducibility of these measurements was conducted by using the intraclass correlation coefficient and the Friedman test.RESULTS:
The mean measured flow rates were slightly lower than the stipulated flow rate at 1 L/min, very close for 3 L/min, and higher for the 5 and 10 L/min flow rates. There was a large variability among the measurements from different flow meters, mainly at low flow rates (1 and 3 L/min). There was no difference between new and used flow meters at the flow rates measured, except at 10 L/min. Flow meters precision analysis showed a good reproducibility in 3 repetitive measurements for each flow rate (minimum 0.95, maximum 0.99 intraclass correlations).CONCLUSIONS:
The flow meters tested showed good precision and poor accuracy.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Oxigenoterapia
/
Fluxômetros
Limite:
Humans
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article