Prehospital Trauma Life Support (PHTLS) Practice Test

In percutaneous transtracheal ventilation, what is the correct ratio of lung inflation to inflation time?

1. 1:4

2. 1:5

3. 1:2

4. 2:2

The correct answer is: 1:4

In percutaneous transtracheal ventilation, the ideal lung inflation to inflation time ratio is 1:4. This ratio is based on the need to allow the lungs sufficient time to inflate and deflate effectively within a single ventilation cycle. A more prolonged inflation time allows for better gas exchange and oxygenation, particularly in emergency situations where the patient may be unable to breathe adequately on their own. Keeping this ratio ensures that the air delivered to the lungs is sufficient to maintain adequate ventilation without causing overdistension or barotrauma to the lung tissue. The other ratios listed do not align with the optimal management of ventilation using this technique. A 1:5 ratio might not provide adequate inflation time, whereas a 1:2 or 2:2 may lead to rapid inflations that do not allow sufficient time for exhalation. Therefore, understanding the appropriate ratio helps ensure patient safety and effective ventilation during emergency interventions.