ELECTRONIC SUPPLEMENTARY MATERIAL
Chest physiotherapy
This treatment consisted of a standard sequence of techniques in three consecutive
stages. At the beginning, assisted mucus clearance techniques (suction, postural, and
manual drainage) were carried out to increase the cough reflex; subsequently, a nebulised
saline solution was applied for 5 min, followed by another sequence of the same
techniques; finally, tracheal suctioning was performed. Additional postures and active
mobilization were encouraged to facilitate removal of secretions during these sequences.
Intrapulmonary percussive ventilation (IPV)
This technique provides continuous gas flow to the patient. A continuous and pulsatile gas
flow (successive subtidal volumes) was delivered to the patients’ airways by means of an
open breathing circuit called Phasitron, whose function is to convert low-flow, highpressure subtidal volumes into high-flow, low-pressure subtidal volumes. In other words,
the Phasitron is a flow/pressure converter based on the Venturi principle associated with a
pneumatic nebulizer. The circuit is a continuously open breathing circuit. This creates a
physiological waveform (the patient inspiratory time corresponding to a pressure decrease)
and a low mean intrapulmonary pressure. This technique may be associated with
nebulization and has the potential to improve secretion clearance. During the percussive
bursts of air into the lungs, a continued pressure is maintained, while a high velocity
percussive inflow opens airways and enhances intra-bronchial secretion mobilization.
In the present study we have used the IMP2 ventilator (Breas Medical AB, Mölnlycke,
Sweden), which has been also used in previous trials (a,b). The device was set at both
variable pressure (1.6 to 2.0 bar) and frequency (200 up to 300 cycles/min) according to
the patient’s tolerance; I/E ratio was set at 1/1.2 and the maximum proximal airway
pressure was limited to 40 cm H2O.
a) Piaggi G, Ceriana P, Lazzeri M, Brivio A, Cirio S, Tonoli A, Nava S. (2004) Physiologic
evaluation of high frequency intrapulmonary percussive ventilation (IPV) in healthy
volunteers. Eur Respir J 24: 315s.
b) Nava S, Barbarito N, Piaggi GC, De Mattia E, Cirio S. (2006) Physiological response to
intrapulmonary percussive ventilation in stable COPD patients. Respir Med 100: 15261533.