Hydrofluoroalkane-beclomethasone versus chlorofluorocarbon-beclomethasone delivery in neonatal models

Inhaled hydrofluoalkane-beclomethasone dipropionate in bronchopulmonary dysplasia. A double-blind, randomized, controlled pilot study

OBJECTIVE

The efficacy of inhaled steroids in spontaneously breathing infants with established bronchopulmonary dysplasia (BPD) is debatable. The inhaled steroid hydrofluoalkane-beclomethasone dipropionate (QVAR) is unique in its small particle size that results in higher lung deposition. Our objective was to determine if inhaled QVAR could decrease respiratory rehospitalizations of infants with established BPD.

STUDY DESIGN

Double-blind, randomized placebo-controlled, multicenter pilot study. Preterm infants with moderate-to-severe BPD were randomized to inhaled QVAR 100 μg per dose or placebo twice daily via Aerochamber with face mask. Treatment was administered daily from recruitment at 36 weeks post menstrual age until 3 months post discharge. Analysis was carried out by intention to treat.

RESULTS

The QVAR (n=18) and placebo (n=20) groups were comparable in birth and recruitment characteristics. Length of stay (108.5±26.3 vs 108.7±36.0 days) and infants requiring oxygen at discharge (5/17 vs 6/19) or at study end (0/17 vs 2/19) were comparable. Respiratory rehospitalizations/infant (0.1±0.5 vs 0.4±0.6), rehospitalization days (0.5±1.5 vs 4.1±10.3), and post-discharge additive inhaled (0.3±0.9 vs 6.4±21.5 days), systemic (0.7±2.8 vs 1.0±1.4 days) and combined (inhaled/systemic) steroids (1.0±2.9 vs 7.8±25.8 days) tended to be lower in the QVAR compared with the placebo group. Blood pressure, height and weight gain, and urine cortisol/creatinine ratio at study end were comparable between groups.

CONCLUSIONS

Our study was unable to detect a significant effect of inhaled QVAR on the respiratory course of established BPD. The study was underpowered. Possible benefits of QVAR could be masked by a tendency toward higher use of additional steroids in the placebo group.

Albuterol delivery via metered dose inhaler in a spontaneously breathing pediatric tracheostomy model

RATIONALE

Little data are available regarding efficiency of drug delivery devices and techniques despite their widespread use in spontaneously breathing tracheostomized patients. We compared patient dose achieved with different devices, inhalation techniques, tracheostomy tube sizes and breathing patterns using a spontaneously breathing tracheostomized pediatric model.

METHODS

A tracheostomy model was connected in series to a breathing simulator with a filter interposed (patient dose). Breathing patterns of a 16-month-old and a 6- and 12-year-old child with tracheostomy with internal diameters (mm) of 3.5, 4.5, and 5.5 were used. Albuterol HFAp MDI was used. Aerotrach Plus, MediBag, Aerochamber MV, Aerochamber Mini, and inline adapter with 6-inch tubing were tested. The latter 3 devices were also tested with assisted technique. Albuterol was analyzed via spectrophotometry.

RESULTS

Aerotrach Plus outperformed almost all devices tested. Aerochamber MV with unassisted technique was the second best and the adapter was the worst. Comparison of efficiency between best and worst performer ranged from 3- to 17.2-fold. The 16-month-old breathing pattern and the 3.5 mm tracheostomy tube had the lowest patient dose. The use of assisted technique decreased patient dose by 18-67% for the 4.5 and 5.5 mm but not for 3.5 mm tracheostomy tubes. A median of 7.4% of the nominal dose was deposited in the tracheostomy tubes.

CONCLUSIONS

Aerotrach Plus and the adapter were the most and least efficient devices respectively. Tracheostomy size and breathing pattern affected drug delivery. The use of assisted technique reduced aerosol delivery.

Design of Facemasks for Delivery of Aerosol-Based Medication via Pressurized Metered Dose Inhaler with Valved Holding Chamber: Key Issues that Affect Performance

Valved holding chambers (VHCs) are widely prescribed for use with pressurized metered dose inhalers (pMDIs) for the treatment of respiratory disease by aerosol therapy. The facemask is the preferred patient interface for use by infants and small children, as well as by geriatric patients, due primarily to poor coordination skills. However, care is required in the design of the facemask-VHC system to optimize the delivery of medication. In particular, it is essential to achieve an effective mask-to-face seal and to minimize the volume of dead space. It is also important to ensure that the fit of the facemask is comfortable to the patient when applied with sufficient force to create a seal. We review each of these design principles and their application in the evolution of a range of VHCs from the same family of devices during the past fifteen years. We also examine the various methods available for evaluating VHC-facemasks as a system, recommending where future work might be directed.

Inhaled drugs for the prevention and treatment of bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is one of the most common long-term complications and treatment challenges in preterm infants. Theoretically, inhaled corticosteroids may suppress pulmonary inflammation without causing systemic side-effects, while bronchodilators will improve airway resistance and thereby work of breathing. This article reviews current data on these drugs in BPD prevention or treatment. Trials published to date have not demonstrated that regular bronchodilator administration influences the incidence of BPD or improves long-term outcome. Inhaled steroids started before 2 weeks of age may improve rates of successful extubation and reduce the need for rescue systemic glucocorticoids, but have not been shown to reduce the incidence of BPD. Thus, their use cannot be generally recommended. The data currently available are not sufficient to give any clearer recommendation on the use of these drugs in infants at high risk of, or established, BPD.