2004 OPEN FORUM Abstracts
High Frequency Percussive Ventilation in a Pediatric Patient with Hydrocarbon Aspiration –CASE REPORT
T Mabe, RRT,
T Honeycutt, MD, B Cairns, MD FACS, K Kocis, MD, MS, K Short, RRT,
RN, Departments of Pediatrics and Surgery, University of North
Carolina Hospitals, Chapel Hill, N.C.
Introduction: Mineral oil is a common remedy to
treat chronic constipation in the pediatric population. Ingestion of
mineral oil by infants and children may not evoke a protective cough
reflex, and ultimately aspiration can occur. Aspiration of
hydrocarbon (mineral oil) can result in severe pneumonitis and in
cases of chronic aspiration it can lead to lipoid pneumonia over
time. We describe the ventilator management of a previously healthy
eleven-month-old male with severe aspiration pneumonitis from mineral
oil using a high frequency percussive ventilator (HFPV), after other
modes of mechanical ventilation failed to improve the status of the
child. The HFPV delivers sub-tidal volumes superimposed on to
conventional type breaths. Short expiratory times can be set to allow
for auto-peep to occur and exhalation is active. The sub-tidal
volumes or percussions inherent in the HFPV allow for effective
mobilization of secretions.
Case: The patient was transferred
to our Pediatric Intensive Care Unit from a nearby hospital,
intubated and ventilated for management of his respiratory failure.
He was initially placed on a conventional ventilator in a pressure
regulated volume control mode for approximately one hour but needed
higher than normal pressures to maintain adequate ventilation. A
decision was made to switch the patient to a pressure
control/pressure support mode (PCV/PSV) on a Servo-i ventilator with
PSV 10, PCV 20-24, PEEP 8, and FIO2 50-80%. ABG’s on these
settings were pH 7.16-7.21, PCO2 46-62, and PaO2 60-120. At the end
of the third day on PCV/PSV, a decision was made to attempt airway
pressure release ventilation (APRV) due to worsening of the patient’s
oxygenation. During an hour trial of APRV, oxygen saturation levels
deteriorated to low levels and a decision was made to place the
patient on the 3100A high frequency oscillator (Sensormedics). The
high frequency oscillator (HFO) settings were Hz 8, amplitude 40-48,
MAP 25-28, and FIO2 50-100%. The patient remained on this mode of
ventilation for 6 days with ABG’s pH 7.38 (±
5), PCO2 50-60, and PaO2 57-100. On the sixth day of HFO, the chest
x-ray showed a worsening of his pneumonia and the patient started to
deteriorate with oxygen saturations in the low 80’s. A decision
was made to try the HFPV (VDR-4) in an attempt to mobilize secretions
and any residual mineral oil. Initial settings on the HFPV were PIP
26, PEEP 8, phase rate 20, percussive rate 600, inspiratory time 2.5
seconds, and FIO2 100%. Immediately after initiating the HFPV and for
four hours following, large amounts of secretions including a thick
oily substance were suctioned from the airways. Within 12-24 hours
oxygenation improved dramatically and FIO2 was weaned to 35%. During
the next 12 hours the patient was weaned off the HFPV onto a
conventional ventilator with a volume support mode and he was
subsequently extubated 48 hours after initiating HFPV.
Discussion:The beneficial use of HFPV in inhalation injuries to facilitate
removal of carbonaceous secretions has been well documented. The
benefits of the intermittent intrapulmonary percussive machine have
been well documented in mobilizing secretions in cystic fibrosis
patients. We observed with this case that HFPV, as an alternative
mode of ventilation successfully mobilized secretions that were
otherwise unobtainable and we believe led to the swift recovery of
this child. HFPV should be given consideration as a mode of
ventilation when mobilization of secretions is an issue. Further
study of the possible expanded use of the HFPV in certain clinical
situations seems to be warranted.