Position of different nebulizer types for aerosol delivery in an adult model of mechanical ventilation

Abstract

BackgroundThe optimal positions of different types of nebulizer for aerosol delivery remain unclear.MethodsThree ICU ventilators employing three types of nebulizer were separately connected to a simulated lung to simulate nebulization during invasive ventilation. Assist/control-pressure control (A/C-PC) mode was utilized, with inspiratory pressure (Pi) set to 12 cmH2O and positive end expiratory pressure (PEEP) set to 5 cmH2O, and with a target Vt of 500 ml. The bias flow of all the ventilators was set to 2 L/min. The three nebulizers were the continuous jet nebulizer (c-JN), the inspiratory synchronized jet nebulizer (i-JN), and the vibrating mesh nebulizer (VMN). The five nebulizer positions were as follows: at the Y-piece (position 1) and 15 cm from the Y-piece (position 2) between the endotracheal tube and the Y-piece, at the Y-piece (position 3) and 15 cm from the Y-piece (position 4) in the inspiratory limb; and at the humidifier inlet (position 5). Aerosols were collected with a disposable filter placed at the simulated lung outlet (n = 3) and were measured by UV spectrophotometry (276 nm). The measurements were compared under different experimental conditions.ResultsThe aerosol delivery of c-JN, i-JN, and VMN was 5.33 ± 0.49~11.12 ± 0.36%, 7.73 ± 0.76~13.75 ± 0.46% and 11.13 ± 56–30.2 ± 1.63%, respectively. The higher aerosol delivery: for c-JN~Positions 2 (10.95 ± 0.15%), fori-JN~Positions 1 or 2 (12.91 ± 0.88% or 13.45 ± 0.42%), for VMN~Positions 4(29.03 ± 1.08%); the lower aerosol delivery: for c-JN~Positions 1, 3 or 5, fori-JN~Positions 4 or 5, for VMN~Positions 5.The highest aerosol delivery:For c-JN at Position 2 (10.95 ± .15%), for i-JN at Position 1 or 2 (12.91 ± .88% or 13.45 ± .42%), for VMN at Positions 4 (29. 03 ± 1.08%); the lower aerosol delivery: for c-JN at Positions 1, 3 or 5, for i-JN at Positions 4 or 5, for VMN at Positions 5. The highest aerosol deliveryof c-JN was lower than that of i-JN while the VMN was the highest (all P < .05). However, no differences were observed between the highest aerosol delivery with c-JN and the lowest aerosol delivery with i-JN. Similar results were found between the lowest aerosol delivery with VMN and the highest aerosol delivery with c-JN /i-JN in the Avea ventilator. There were no differences in the highest aerosol delivery of each nebulizer among the different ventilators (all p > 0.05).ConclusionDuring adult mechanical ventilation, the type and position of nebulizer influences aerosol delivery efficiency, with no differences between ventilators.

The Use of an Inspiration-Synchronized Vibrating Mesh Nebulizer for Prolonged Inhalative Iloprost Administration in Mechanically Ventilated Patients—An In Vitro Model

“…The nebulizers were placed according to their already-known optimal position in the ventilation circuit: the VMN syn between the ETT and the Y-piece adapter, and the VMN cont 15 cm upstream on the inspiratory limb using extra tubing [ 18 , 20 , 22 ]. The nebulizer positions are also shown in Figure 1 .…”

Aerosol therapy in adult critically ill patients: a consensus statement regarding aerosol administration strategies during various modes of respiratory support

“…When comparing aerosol delivery via MV, in vitro [18][19][20][21][22][23][24][25][26] studies reported a higher aerosol delivery efficiency with vibrating mesh nebulizer (VMN) than continuous jet nebulizer (JN), regardless of the nebulizer placement and ventilator settings. A bioavailability study in mechanically ventilated patients also showed a higher percentage of urinary salbutamol levels with VMN than continuous JN [27].…”

High-Dose Nebulized Colistin Methanesulfonate and the Role in Hospital-Acquired Pneumonia Caused by Gram-Negative Bacteria with Difficult-to-Treat Resistance: A Review

“…Administration of high-dose nebulized colistin is mainly performed by VMN, as observed in recent studies [ 19 , 20 , 21 , 22 , 52 , 53 ]. In order to optimize drug delivery, the best VMN position in the circuit is 15 cm from the Y-piece in the inspiratory limb [ 44 , 45 , 54 ]. A comparison of the nebulizer generator devices is presented in Table 1 [ 13 , 35 , 42 , 43 , 44 , 51 ].…”