The Science Journal of the American Association for Respiratory Care

2011 OPEN FORUM Abstracts


Eribaweimon Shilla, Dr Leslie E. Simon Lewis; Respiratory Therapy, Manipal College of Allied Health Sciences, Manipal, Karnataka, India

ABSTRACT OBJECTIVE: To evaluate the fraction of delivered oxygen (FDO2) concentration using a standard self-inflating bag (VBM of 250 ml capacity) with a pressure gauge manometer without a reservoir at different oxygen flow rates. To compare the FDO2 at different peak inspiratory pressure (PIP) of 20 cm H2O and 30 cm H 2O. METHODS: The test is done on a neonatal test lung and the average of best two readings was taken. The required equipment to start are Drager Baby Log 8000 plus flow sensor calibrated, 'Y' adaptor with two neonatal test lungs, VBM self-inflating bag with a pressure gauge without a reservoir, flowmeter with an oxygen tubing (112 cm) to set flow rate of oxygen and an oxygen analyzer along with a time recorder to measure the percentage of FDO2 at different timing. The FDO2 was recorded at 1 minute up to 5 minutes by setting a timer. The FDO2 was recorded at each flow rate at two different PIPs. The respiratory rate was fixed at around 40 breaths per minute and the tidal volume range at each PIP was also recorded. RESULT: The mean FDO2 concentration was slightly lower in the first one minute and gradually increased. The FDO2 ranges from 50% to 85% at different flow rates. The FDO2 measured in the entire test from 1L/m to 10 L/m flow rate showed a mean ± SD of 71.85% ± 11.49 with PIP of 20 cmH2O, mean ± SD of 64.60% ± 11.58 with PIP of 30 cmH2O. The FDO2 between two PIPs showed a mean ± SD of 68.22% ± 5.12. The average mean tidal volume at different PIP was 27ml and 36ml approximately. CONCLUSION: Oxygen delivery was consistently more than 60% with standard neonatal resuscitation bag without reservoir with oxygen flow rate above 2l/min. The FDO2 in this test differed from the information contained in the Standard Guidelines of Neonatal Resuscitation regarding self-inflating bag without a reservoir. The drop of FDO2 with a PIP of 30 cm H2O is due to more entrainment of air into the self-inflating bag which blends and hence decreases the oxygen concentration. Preterm /Asphyxiated neonates requires restriction of oxygen flow rate of less than 2l/min when used for resuscitation without reservoir in absence of standard blenders to deliver oxygen below 60%. Sponsored Research - None FDO2% increses with change in flow rate at different PIP