apnea test
Diagnostic procedure that temporarily removes ventilatory support to assess a patient's spontaneous breathing drive and neurological status.
Full Definition
An apnea test is a critical diagnostic procedure used to evaluate brain death or assess respiratory drive in mechanically ventilated patients. The test involves temporarily discontinuing ventilatory support while closely monitoring the patient's ability to initiate spontaneous breathing. During the test, carbon dioxide levels are allowed to rise to stimulate the respiratory centers in the brain. If no spontaneous respiratory effort occurs despite adequate CO2 stimulation, it may indicate severe neurological impairment or brain death. The test requires careful preparation and monitoring to ensure patient safety.
Usage
Usage note: Distinguished from weaning trials, which assess readiness for ventilator discontinuation in recovering patients.
In Context
- "The neurologist ordered an apnea test to confirm brain death before proceeding with organ donation protocols." — Medical chart documentation
- "During the apnea test, the patient showed no respiratory effort despite CO2 levels reaching 60 mmHg." — Clinical assessment report