Laboratory evaluation of the Vortran Automatic Resuscitator Model RTM

Area of Science:

• Mechanical Ventilation
• Respiratory Physiology
• Medical Device Evaluation

Background:

• Emergency ventilation is crucial for patients with respiratory failure.
• The Vortran Automatic Resuscitator is a proposed device for emergency ventilation.

Purpose of the Study:

• To evaluate the Vortran Automatic Resuscitator's performance under simulated respiratory loads.
• To test if increasing load (resistance, decreasing compliance) affects minute alveolar ventilation.

Main Methods:

• A passive lung model was used with the Vortran Automatic Resuscitator.
• Eight combinations of lung compliance and resistance were tested with varying gas flow.
• Tidal volume, frequency, and ventilation parameters were measured and analyzed.

Main Results:

• Minute alveolar ventilation varied significantly, ranging from zero to 9.8 L/min.
• Tidal volume decreased, and frequency increased with higher loads.
• Calculated P(aCO(2)) was consistently outside the normal range (35-45 mm Hg).

Conclusions:

• The Vortran Automatic Resuscitator exhibited inappropriate minute alveolar ventilation across tested conditions.
• Variable performance and lack of alarms suggest caution for unsupervised emergency use.
• Device performance is affected by patient lung mechanics (compliance, resistance).