Preliminary evaluation of high-frequency chest compression for secretion clearance in mechanically ventilated patients

A high-frequency chest compression (HFCC) device called the ThAIRapy System has been developed to provide secretion clearance therapy. We evaluated the safety, efficacy, and utility of the device in long-term mechanically ventilated patients. DESCRIPTION OF DEVICE: The primary components of the device are an air-pulse generator and an inflatable vest. Small gas volumes are alternately injected into and withdrawn from the vest by the air-pulse generator at a fast rate, creating an oscillatory or vibratory motion. The pulses cause the vest to inflate and deflate against the thorax of the patient.

We evaluated HFCC by comparing it to percussion and postural drainage therapy (P&PD); sputum production, patient comfort (PC), pulse-oximetry saturation (SpO2), heart rate (HR), and blood pressure (BP) data were collected and compared between the 2 methods. We monitored the reliability of the device and distributed a survey questionnaire to the entire respiratory therapy staff to assess utility.

Nine patients completed the safety and efficacy portion of our evaluation. No significant difference was found between P&PD and HFCC in the wet weight of collected sputum, the mean change-in-percent of SpO2 or the mean percent change from baseline in HR, BP, or PC. All therapists believed that the ThAIRapy System was easy to learn, and 70% considered it an acceptable alternative to P&PD. Of the staff members surveyed, 80% believed that use of the HFCC device resulted in time savings in all or most cases. There were no equipment malfunctions in 225 hours of use.

Compared to P&PD, HFCC via the ThAIRapy System may be equally efficacious in promoting secretion clearance in long-term mechanically ventilated patients. HFCC is neither more nor less safe for patients than is P&PD using SpO2, HR, BP, and PC as outcome variables. Most of our respiratory therapists perceived HFCC as an acceptable alternative to P&PD.