 |
EVALUATION OF NEONATAL TIDAL VOLUMES
USING THE FLORIAN GRAPHICS MONITOR.
Brian Glynn, BS RRT. Raymond
Malloy, BS RRT,William Bucher RRT,Thomas H. Shaffer PhD, Wendy S. Sturtz, MD,
Suzanne M. Touch, MD, Jay S. Greenspan, MD. Departments of Pulmonary Care and
Neonatology, Thomas Jefferson University Hospital (TJUH), Philadelphia, Pa.
BACKGROUND: At TJUH, the Sensormedics
3100A High Frequency Oscillator (HFOV) is used to improve ventilation and oxygenation
in neonates with respiratory failure who have not responded to conventional
modalities. To optimize lung protective strategies, the goal is to achieve tidal
volumes of 4-6ml/kg and these are conventionally thought to be less than physiologic
dead space volume. As the Sensormedics 3100A Oscillator does not have in-line
monitoring, an external monitor was utilized to track the infants? tidal volumes
during routine care, and these values were compared.
HYPOTHESIS: This study was
an attempt to validate that tidal volumes are less than dead space volume.
Methods: Five infants on the
Sensormedics 3100A HFOV with chronic lung disease and without air leak were
monitored. Tidal volume and tidal volume per kg were recorded using hot-wire
anemometry (Florian: Acutronic Medical Systems). The range of HFOV settings
were MAP (12-19 cm H2O), amplitude (18-40 cm H20), f (8-12
hz), and inspiratory time (0.33).
Results:
| pt |
weight (kg) |
mean tidal
volume(ml) |
mean tidal
volume/kg |
estimated
physiologic
tidal vol. |
estimated
dead
space vol. |
| 1 |
1.1 |
2.9 |
2.84 |
8.25 |
2.75 |
| 2 |
0.96 |
2.61 |
2.72 |
6.72 |
2.24 |
| 3 |
0.84 |
2.63 |
3.13 |
6.3 |
2.1 |
| 4 |
1.19 |
1.96 |
1.65 |
8.92 |
2.97 |
| 5 |
1.04 |
3.37 |
3.24 |
7.8 |
2.6 |
| |
estimated
physiologic tidal volume-7-8 ml/kg |
| |
estimated
dead space volume-1/3 of physiologic(2.5 ml/kg) |
CONCLUSION: The above data
indicates that measured tidal volume/kg during HFOV is equivalent to if not
greater than expected dead space volume in 4 out of 5 patients. Although the
tidal volumes are greater than dead space volume, the tidal volumes remain below
the goal of 4-6ml/kg to achieve optimal lung protective strategies. The Florian
Graphics Monitor may be useful in optimizing ventilation during oscillation,
and may be useful in reducing the need for arterial blood gas draws to assess
ventilator-patient interaction.
OF-02-108
|
|
