Monday, January 3, 2011

Shook to Death: a Case Study of High-Frequency Chest Wall Compression


There are a variety of techniques used as "Chest Physical Therapy" (CPT), for patients with airway diseases. The main goal of these therapies is to augment secretion mobilization & airway clearance[1].

One of these techniques utilizes high-frequency chest wall compression a.k.a "The Vest" (® Hill-Rom). The manufacturers of the Vest list numerous conditions that the device may be used for, from patients with chronic respiratory conditions-to-Acute Respiratory Distress Syndrome[2].

Conversely, there are no contra-indications, considerations when not to use the device, or patients that may be at risk listed in the product information.

Additionally, there is no supporting evidence that high-frequency chest wall compression is more valuable than conventional CPT (Schans, 2007).

Clinical Overview

A 70 year old male patient was prescribed CPT via Vest Therapy due to copious secretions and atelectasis.
Pre-therapy the patient was admitted to a non-intensive care unit bed, hemodynamically stable, and oxygenating sufficiently (only requiring a nasal cannula to maintain a SPO2 > 92%).

The patient tolerated the initial Vest therapy well without any complications. After a subsequent therapy the patient went into cardio-pulmonary arrest secondary to mucus plugging. The patient survived the event, placed on mechanical ventilation, and bronchoscopy was performed to remove the plug. After an extended intensive care unit stay the patient was transferred to a general hospital bed in stable condition.

While waiting for discharge planning and placement the patient was again ordered for CPT therapy via Vest for secretion management. After subsequent therapies the patient went into cardio-pulmonary arrest. Again the patient survived, was placed on mechanical ventilation, and admitted to the ICU. Unfortunately, the patient had multiple complications with the ICU stay and did not survive.


Airway mobilization is very different then airway clearance, if the patient cannot clear secretions the primary focus should be on clearance techniques: suctioning, or bronchoscopy.

Additional Considerations[3]

  • Is there rationale for this therapy, are the secretions compromising gas exchange or lung mechanics?
  • "What is the potential for adverse effects"?
  • "Which therapy is likely to provide the greatest benefit with the least harm"?

[1] Schans, C. (2007). Conventional Chest Physical Therapy for Obstructive Lung Disease. Respiratory Care. 52 (9): 1198.
[2] Hill-Rom. The Vest ® Airway Clearance System Model 205. Product Information.
[3] Hess, D. (2002). Secretion Clearance Techniques: Absence of Proof or Proof of Absence? Respiratory Care. 47 (7): 757 editorial.