2007 OPEN FORUM Abstracts
A CASE SERIES OF INFANTS ON APRV IN THE NEONATAL ICU
P. Garcia1, J. Henry1, S. Hughes1, C. Boylan1
INTRODUCTION: Airway Pressure Release Ventilation (APRV) has been used in adults and pediatrics to treat patients with diffuse lung disease. However, there is little published data on APRV and its use in the neonatal intensive care unit (NICU). This was a case series review of APRV used in the Johns Hopkins Hospital’s NICU as a mode of ventilation in 15 neonates over a three year period. Infants in our NICU were placed on APRV for various complications. APRV was used as either a rescue or pro-active mode of ventilation.
CASE SERIES: We studied initial diagnosis upon admission to the NICU, diagnosis when placed on APRV, number of days on APRV and whether the infant was successfully weaned from APRV. Differentiation of APRV use was made as either proactive or rescue therapy. The term "pro-active" was used for worsening clinical status prior to deterioration in blood gases. The term "rescue" was used for patients with progressively worsening blood gases or failing other conventional modes of ventilation (CMV). Differentiating between the two reasons for using APRV was an important factor in determining which patients may benefit from APRV.
The patient population reviewed in this series included infants born at gestational ages ranging from 24 to 40 weeks postconception. APRV was initiated from 1 day to 7 months of life. Therapy ranged from 1 day to 28 days, with a mean of 6.27 days. Initial settings on APRV were as follows: Tlow 0.2-0.4sec, Thigh 2-4.5sec, Plow 0-2 cmH2O, Phigh 22-34 cmH2O and was selected based on blood gas results, chest x-rays and pulse oximetry. Results demonstrate that overall patients placed on APRV had a 56% mortality rate. Rescue use of APRV had a 75% mortality rate, while patients who were placed on APRV pro-actively were able to be weaned to CMV or nasal CPAP 75% of the time. In addition patients with necrotizing enterocolitis, ostomies or Congenital Diaphragmatic Hernias responded positively in 75% of the cases, as shown by improved blood gases.
Conclusion: Infants having additional congenital defects were more difficult to manage using APRV. However, patients with increased abdominal pressure tended to respond well to APRV. Use of APRV pro-actively improved patient blood gases and mechanical ventilation weaning. APRV was less successful when used as a rescue mode of ventilation. A randomized study of APRV in the neonatal population would further establish the optimal patient population that would most benefit from APRV.