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.