Introduction: Aerosolized albuterol is commonly used in the treatment of neonatal respiratory illnesses. Clinical and in vitro studies have identified numerous factors that affect aerosol drug delivery during neonatal mechanical ventilation, including the choice of metered-dose inhaler (MDI) or nebulizer, the use of a holding chamber, time between actuations, the volume of nebulized solution, and the position and placement of the nebulizer or MDI. Because there is no consensus on the optimal method of administration, there is probably substantial variability among institutions in how aerosolized albuterol is administered to mechanically ventilated infants in the neonatal intensive care unit (NICU).
Objective: Survey academic medical centers in the United States regarding their practices of administering aerosolized albuterol to intubated newborns in the NICU.
Methods: A survey instrument was developed that queried 18 aspects of albuterol administration in mechanically ventilated infants, including the frequency of MDI and nebulizer use, the average and maximum dose, the time between MDI actuations and following the final actuation, the use of a holding chamber, and the placement location of the holding chamber or nebulizer. Respiratory therapists and respiratory therapy managers having direct knowledge of neonatal clinical practices in their neonatal fellowship program NICUs were surveyed via telephone. Those who did not respond via telephone were surveyed via fax.
Results: Eighty institutions were surveyed and there were 68 respondents (85% response rate). Responders averaged 35 +/- 13 NICU beds and 11 +/- 5 ventilators/d. Nineteen percent of the respondents reported administering albuterol via MDI 100% of the time; 22% use MDIs 75-99% of the time; 9% use MDIs 50-74% of the time; 4% use MDIs 25-49% of the time; and 43% never use MDIs to deliver albuterol. The average dose via MDI was: 1 puff: 30%; 2 puffs: 65%; and 4 puffs: 5%. The maximum dose via MDI was: 2 puffs: 30%; 3 puffs: 14%; 4 puffs: 36%; 6 puffs: 11%; and 8 puffs: 6%. Thirty-one percent of the respondents place the holding chamber in-line with the ventilator circuit, 56% administer the aerosol via manual ventilation, and 13% use both methods. Fifty-six percent place the in-line holding chamber between the endotracheal tube and ventilator circuit, and the other 44% place the in-line holding chamber in the inspiratory limb. The time between MDI actuations depended on whether the holding chamber was placed in-line or the aerosol was administered via manual ventilation (MV): < or = 0.5 min: 18% in-line and 28% MV; 1 min: 47% in-line and 43% MV; 2 min: 6% in-line and 4% MV; 3 min: 6% in-line and 0% MV. Eighty-three percent of respondents indicated that dead space introduced by a holding chamber/spacer was not a concern. Forty-three percent use nebulizers exclusively to administer albuterol to mechanically ventilated patients. Seventy-four percent of centers that nebulize albuterol use a dose of 1.25-2.5 mg. Eighty-eight percent of the surveyed institutions place nebulizers in-line with the ventilator circuit, and the other 12% use manual ventilation to administer the nebulized aerosol. Of those that use in-line nebulization, 95% place the nebulizer in the inspiratory limb of the circuit, and the other 5% place the nebulizer between the endotracheal tube and circuit Y-piece. Among centers that place the nebulizer in the inspiratory limb, 52% place it adjacent to the circuit Y-piece, 36% place it midway upstream in the inspiratory limb, and 12% place it near the humidifier.
Conclusion: There is substantial variability among NICUs in albuterol administration to mechanically ventilated infants, with the majority of institutions now administering albuterol via MDI.