2004 OPEN FORUM Abstracts
Safety and Feasibility of Inhaled Nitric Oxide Delivery with High-Frequency Jet Ventilation.
Hooshang Baghaee
1, Kabir M Abubakar 2
and Martin Keszler 2. 1Respiratory
Care and 2Pediatric/Neonatalogy,
Georgetown University, Washington, DC
Background:
Inhaled Nitric Oxide (iNO) is commonly delivered via high frequency
oscillatory ventilation (HFOV) in infants with hypoxic respiratory
failure. Such infants often need to be transported to a center with
extracorporeal membrane oxygenation (ECMO) capabilities. High
frequency jet ventilation (HFJV, Bunnell Inc, Salt Lake City, UT) is
the only form of HFV feasible in transport. HFJV offers advantages
over HFOV in infants with airleak and is the preferred mode in many
centers. Bench studies showed that iNO can be delivered reliably
using HFJV and INOvent delivery system (Datex-Ohmeda, Madison, WI)
but the combination has not been studied in infants, nor validated by
the company. The product advisory warns against this combination
because of concern that high pressure in the HFJV circuit may cause
device failure.
Objective: To evaluate feasibility and
safety of HFJV+INOvent during transport and NICU use.
Design/Methods: The INOvent injector module was adapted
into the HFJV circuit so that iNO is delivered proximal to the
humidifier. Nitric oxide (NO), nitrogen dioxide (NO2) and
FiO2 were measured just proximal to the endotracheal tube.
This circuit was used both in the NICU and on transport. We
retrospectively examined ventilator variables, NO2 levels,
technical problems and outcomes from the records of all infants who
received iNO therapy+HFJV from 1999 to 2003.
Results:
HFJV+iNO were used in 43 infants for a median of 88 h (range 2-346).
Median gestational age was 39 wk (range 25-42). 7 infants were <34
wk. Median weight was 3460 g (range 690-5178). Six infants needed
ECMO and 6 died (3 with pulmonary hypoplasia, 1 sepsis and 2 birth
asphyxia). Eight patients had airleak, none developed new airleak
while on HFJV+iNO.
| PIP (cmH2O) | MAP (cmH2O) | Circuit Pressure (PSI) | NO conc. (PPM) | NO2(PPM) | |
| Maximum | 50 | 21.4 | 9.8 | 29 | 0.9 |
| Mean (range) | 31 (18-50) | 13 (4.6-21.4) | 4.5 (1.8-9.8) | 13.8 (1-29) | 0.19 (0.1-0.9) |
No device failure
occurred during 3525 hours of use, including 28.8 hours during
transport. HFJV circuit pressure (servo-pressure) ranged from 1.8-9.8
psi and was >5 psi for a total of 847 hours. No mechanical
problems with the system were noted except battery failure either due
to early power depletion or improper use of the power pack. There was
no substantial discrepancy between set and measured NO
concentrations.
Conclusions: The combination of
HFJV+INOvent therapy is feasible during transport and NICU use and
achieves outcomes comparable to other combinations of iNO and
ventilatory support. No safety concerns were identified.