OBJECTIVE: To determine if Oxygen (02) requirement changes with inhaled Nitric Oxide (iNO) in babies with severe chronic lung disease (CLD) of prematurity.
BACKROUND: Babies with severe CLD of prematurity who are dependent on the ventilator often require significantly high inspired 02 concentration as the disease progresses. Lung injury and associated pulmonary hypertension reported in these babies is thought to be due in part, to continuous oxidant damage which is related to the amount of inspired 02. Since iNO is known to selectively decrease pulmonary vascular resistance and potentially improve ventilation perfusion, we theorize that low dose iNO will reduce 02 requirement in premature babies with CLD of prematurity.
METHOD: 6 premature babies with initial diagnosis of respiratory distress syndrome were studied using the VIP Gold Ventilator to optimize ventilation and oxygenation. Inclusion criteria include > 2 wks old and 02 requirement of >0.60. iNO was started at 10ppm and weaned to 5 ppm and then to 1 ppm for 02 saturations >92% before discontinuation. FI02 was weaned by 2-4% and 02 saturations were maintained between 88 and 92%. All MetHb levels were <2 during the study.
| Duration (days): | Gest. Age: | Day of life on NO: | FI02: (pre) | FI02: (post 1 hr) | FI02: (5 days on NO) | FI02: OFF NO |
| 17 | 27 | 53 | 60 | 40 | 50 | 60 |
| 6 | 30 | 92 | 60 | 40 | 25 | 25 |
| 1 | 29 | 13 | 100 | 100 | 100 | 100 |
| 3 | 25 | 27 | 100 | 100 | 50 | 40 |
| 19 | 27 | 18 | 100 | 96 | 78 | 58 |
| 22 | 26 | 48 | 100 | 70 | 54 |
70 |
Results: The patients studied were started on iNO at a mean age of 41.8 days of life. Average gestational age was 27.3 weeks. FI02 requirement decreased by an average of 12.3% after 1 hour on iNO and by an average 27.1% after 5 days on iNO. FI02 requirement decreased by an average of 27.8% after iNO was discontinued.
CONCLUSION: These data suggest that 02 dependent chronically ventilated premature babies may benefit from low dose iNO by requiring less inspired oxygen concentration. This may potentially reduce lung injury and associated morbidity and mortality. Further studies need to be done to determine the efficacy, possible complications and for how long low dose iNO can be used for these babies.
OF-02-045