2004 OPEN FORUM Abstracts
HFPV and High PEEP Strategy in the Management of Severe Inhalation Injury –case report
B Cairns, MD, FACS , K Short
RRT, RN, L Shapiro RRT, T Mabe RRT, M Peck, MD ScD, FACS , F Byerly,
MD, North Carolina Jaycee Burn Center, UNC
Hospitals, Chapel Hill, N.C.
Introduction: Due
to the multifactorial nature of the injury, inhalation injuries
remain one of the greatest challenges in managing critically injured
patients. Ventilator management of severe inhalation injuries present
clinicians with a multitude of problems which can include airway
obstruction and in some cases severe hypoxemia. We describe the
ventilator management of 2 children with severe inhalation injuries
following a tragic trailer fire in which 6 siblings died.
Case:
The two previously healthy children ages 6 and 10 presented to our
burn intensive care unit intubated and with carbon monoxide levels of
45 and 65 respectively. They were subsequently placed on high
frequency percussive ventilation. The initial settings on HFPV were
PIP’s of 40-44, rates of 10-16, pulsatile frequency of 600, a 2
second inspiratory time, PEEP 8-10, and FIO2 of 100%. Over a period
of 48 hours, the FIO2 was weaned to 60% and as expected, large
amounts of carbonaceous secretions were suctioned from the airways
with intermittent plugging caused by sloughing of the airways.
During the first forty-eight hours on HFPV, the ABG’s were pH
of 7.31-7.33, PCO2 of 31-35, PaO2 of 80-104, HCO3 of 17-20.
Hemodynamic monitoring was accomplished through #3 french PICCO
catheters. Over the next 7 to 8 days, the PaO2’s on both
children began to decrease and the HFPV was not able to adequately
oxygenate the children. PaO2/FIO2 ratios were less than 150. Both
children had required 2 chest tubes each at this point. Other modes
of ventilation such as high frequency oscillation and airway pressure
release ventilation were not available at this time in this
institution. Due to a severe worsening of their hypoxia, a decision
was made to switch to a conventional ventilator (Siemens 300) using
the PRVC mode and a high PEEP strategy. The initial PEEP levels were
started at 10 but were subsequently increased to 20 and 22 with PIP’s
reaching 55-60cm H2O. VT’s were 325-375, respiratory rates
were16, and I:E ratios were 2:1 and 1:1. Mean airway pressures were
maintained at 37-39. More chest tubes were placed during the course
of the high PEEP strategy for a total of 6 for each child. On the
high PEEP strategy ABG’s were pH 7.24-7.27, PCO2’s of
56-63, PO2’s of 76-125, HCO3’s of 21-26. Over the course
of 24-48 hours, both children were weaned off the high PEEP levels
and subsequently weaned from conventional ventilation on ICU days 21
and 32 respectively.
Discussion: As previously stated,
inhalation injuries are one of the greatest challenges in critical
care medicine. The use of High PEEP in refractory hypoxemia has been
well documented. These cases show that using alternative ventilator
management strategies were important to the survival and ultimate
positive outcome of these children.