2007 OPEN FORUM Abstracts
AN INVESTIGATION OF AIRWAY PRESSURE RELEASE VENTILATION (APRV) IN BURN PATIENTS
K. A. Short1, L. Shapiro1, B. A. Cairns1, F. Byerly1, M. Kessler1, S. L. Phillips1
Background: Critically ill patients with burn and inhalation injuries often require mechanical ventilation support for adequate oxygenation and ventilation. As patients deteriorate, most require increasing pressures; both Positive End Expiratory Pressure (PEEP) and Positive Inspiratory Pressures (PIP). Airway Pressure Release Ventilation (APRV) has become an increasingly more popular mode for managing burned victimsâ ventilatory and oxygenation needs. APRV uses lower pressures and appears to be a âgentlerâ ventilator mode, improving oxygenation by decreasing the high PIPs that are often used with inhalation injured patients. The primary purpose of this retrospective review is to validate the efficacy of APRV by evaluating the change in PCO2 and PaO2 / FIO2 ratio after the initiation of APRV therapy.
Methods: This is a retrospective review of 32 random patients admitted to the North Carolina Jaycee Burn Center between September 2003 through March 2006 with varying percentages of Total Body Surface Area (TBSA) burns and inhalation injury. Arterial Blood Gases (ABGs) were obtained while on other modes of ventilation, immediately after placement on APRV, and again at least 8 hours but no greater than 24 hours after placement on APRV. Data was then collected on ABGs, demographics, ventilator settings and sedation types and amounts. This data was then analyzed to identify deviations from baseline that occurred in oxygenation and ventilation.
Results: Of the 32 patients reviewed, 66% (21 patients) had a significant improvement in PCO2 (defined as â¥ 5 point change in baseline PCO2 obtained prior to placing pt. on APRV). An additional 31% (10 patients) had no significant change in PCO2 (less than 5 point change), and 1 patient had a rise in an already high PCO2. Likewise, 88% (28 patients) had a rise in PaO2/FIO2 ratio (defined as an increase >/= 30 points). 6% (2 patients) had an increase in PaO2/FIO2 ratio less than 30 points and 6% (2 patients) had a decrease in PaO2/FIO2 ratio greater than 30 points.
Conclusion: This study suggests that APRV can be considered a beneficial therapeutic alternative in burned patients with inhalation injury who do not respond to other modes of ventilation. In this analysis, APRV increased oxygenation while stabilizing ventilation in patients placed on APRV for a minimum of 8 hours.