The Science Journal of the American Association for Respiratory Care

2004 OPEN FORUM Abstracts

COMPARISON OF ACTUAL AND SET PRESSURE LEVELS IN BUBBLE AND INFANT FLOW CPAP DELIVERY DEVICES.



Raymond Malloy BS RRT, Brian Glynn BS RRT, Hemant Desai MD, Jacqueline Sullivan PhD RN Departments of Pulmonary Care, Nursing and Neonatology, Thomas Jefferson University Hospital, Philadelphia, PA

BACKGROUND: Neonates diagnosed with RDS are often treated with Continuous Positive Airway Pressure (CPAP) to prevent intubations and to extubate earlier from the ventilator. At TJUH infants are placed on the Infant Flow System or Bubble CPAP. Pressure is monitored internally with the Infant flow System and an external manometer is placed in line with Bubble CPAP.

HYPOTHESIS
: Actual delivery CPAP may be statistically significantly different from intended/set CPAP. Discrepancy between actual delivery CPAP and intended/set CPAP may be statistically significantly different between Infant Flow System and Bubble CPAP delivery systems.

METHODS:
An external CPAP pressure box was placed in line to measure actual/delivery pressure levels compared to intended/set levels. Data points were taken continuously at a rate of 1 per second using Imagiprobe 3.0 software. Eight liters/minute flow were delivered through both CPAP devices. One hundred data points were collected. Descriptive statistical analysis yielded mean actual/delivery CPAP measurements for both Infant Flow System and Bubble CPAP. Discrepancy scores were generated to measure differences between actual/delivery CPAP measurements and intended/set CPAP. Mean discrepancy scores for the Infant Flow System and Bubble CPAP were subjected to inferential statistical analysis to determine significant differences in delivery discrepancy between the two systems.

RESULTS:

CPAP DEVICE INTENDED/SET CPAP MEAN ACTUAL DELIVERY CPAP MEAN DISCREPANCY SCORE t statistic p value
Bubble 5 cm H2O 6.28 (SD = 1.038) -0.8081 (SD = 1.193) -2.153 0.034
Infant Flow System 5 cm H2O 5.47 (SD = 0.564) -0.4758 (SD = 0.564)

CONCLUSION: Discrepancy between actual delivery CPAP and intended/set CPAP was significantly higher in Bubble CPAP delivery systems as compared to Infant Flow Systems (t = -2.153, p = 0.034, 1 – B = 0.97).