Chest Physiotherapy and Cystic Fibrosis: Mechanical Percussors
The largest falls in saturation were noted during the percussion phase of treatment irrespective of whether or not subjects were receiving supplemental oxygen. Zidulka et al (1989) found that continuous percussion resulted in significant atelectasis in dogs, but oxygen levels decreased and then improved with this technique. The authors postulated that percussion may increase the rate of air movement out of the alveolus (thus resulting in altered surfactant and increased atelectasis) and that the improvement in oxygen levels may result from the removal of secretions or augmented alveolar ventilation. These investigators concluded that if percussion induces atelectasis in humans, then deep breathing should be performed before and after percussion.
Percussion should be used in conjunction with other techniques such as PD, FET, and the active cycle of breathing technique (ACBT) in patients who have copious secretions which cannot be removed by other means. more
During the 1970s, mechanical percussors were introduced as an aid to independent treatment for patients with chronic suppurative lung conditions. Maxwell and Redmond (1979) and Flower et al (1979) compared multimodality CPT by a physical therapist with PD and percussion via a mechanical device in a group of CF patients and found no significant difference in PFTs or sputum volume. It was suggested that mechanical devices were as effective as CPT and would be a useful alternative in home programs.
In 1981, mechanical percussion and PD were compared with manual percussion, the FET, and PD in a study conducted by Pryor et al (1981). Small but significant improvements in (FEVi) and forced vital capacity followed manual percussion, FET, and PD. There was no significant difference in the rate or volume of sputum expectorated between the two treatment groups, and it was concluded that no additional benefit was gained from the use of a mechanical percussor if the patient was using PD assisted by the FET.