1998 OPEN FORUM Abstracts
THE ACCURACY OF OXYGEN LITER FLOW INDICATION BY BOURDON GAUGE E-CYLINDER REGULATORS, WITH AND WITHOUT NASAL CANNULA.
Felipe Rodriguez, BS, RRT; Leslie Ramirez, BS, RRT; Arthur Jones, EdD, RRT. David Shelledy, PhD, RRT. The University of Texas Health Science Center at San Antonio.
Questions: What is the degree of accuracy for flow indication by Bourdon gauge E-cylinder regulators? Does attachment of a nasal cannula significantly affect the flow delivered by the regulators? Methods: A Timeter RT-200 (TM) calibration analyzer measured the flow delivered by Bourdon gauge transport regulators that were in clinical use at a large medical center. The measurements were applied to 48 different regulators at flow rates set to 2, 4, and 6 liters/min, respectively. The measurements also were made both with, and without nasal cannula attached. Flow indication and delivered flow were recorded for each cannula condition and liter flow adjustment. A spreadsheet computed statistics of variability and the independent samples t-test for differences between flows, with and without, cannula. Results: There were no significant differences in delivered flow attributable to attachment of nasal cannula at any of the set flow rates (2 L/min p = 0.48, 4 L/min p = 0.48, 6 L/min p= 0.46). Descriptive statistics for the performance of the flow regulators (N=48) appear in Table 1.
Table 1 Descriptive statistics for measured O2 liter flows
Without cannula With cannula
Set flow N 2 L 4 L 6 L 2 L 4 L 6 L
Measured Mean 48 2.70 5.21 7.65 2.71 5.20 7.68
Measured S.D. 48 0.861 1.295 1.77 0.884 1.266 1.807
Measured Min 48 0.95 3.68 5.80 0.94 3.66 5.80
Measured Max 48 6.40 12.10 16.40 6.60 11.80 16.80
Conclusions: Bourdon gauge E-cylinder transport regulators demonstrate excessive levels of variability between set and delivered flow rates. Attachment of a nasal cannula to a Bourdon gauge regulator is not associated with statistically significant differences in delivered flow rate.
The 44th International Respiratory Congress Abstracts-On-Disk®, November 7 - 10, 1998, Atlanta, Georgia.