A patient may be placed on mechanical ventilation for a number of reasons, i.e. respiratory failure, cardiac arrest, traumatic event, etc. Whichever reason the patient is placed on the ventilator the goal is to remove them from it once the patient is able to breathe and maintain their vitals. When a patient is intubated and placed on a ventilator they will be moved to a critical care setting most likely an Intensive Care Unit, where they will be closely monitored by a team of physicians, nurses, and respiratory therapists. There are several tests that are frequently done to monitor the patient including blood sampling, cognitive and physical movement tests (shrug the shoulders, squeeze my hand), not to mention the patient is on the monitor. The monitor records heart rate and rhythm, blood oxygen saturation, blood pressure, and exhaled carbon dioxide generally.
The ventilator measures every breath delivered and exhaled through a closed circuit. Ventilators today are very advanced and can monitor numerous amounts of information. The ventilator measures the pressures and volumes of delivered breaths, the rate at which the patient is breathing, the patients’ minute ventilation and several other numbers. Most ventilators even offer flow-volume loops and graphs to help understand the amount of volume and pressure given. The nurse and respiratory therapist monitor the patient closely for any changes, they also can clear the patient’s airway with an inline suction catheter, which keeps the tube and the airway clear. There are also safety measures taken to ensure the patient does not remove the breathing tube, soft restraints are used usually. The patient should be placed above a thirty degree angle in bed and the oral cavity should be kept clean. These measures are taken to prevent ventilator associated pneumonia (VAP). There are many other actions taken to avoid complications.
There are a number of tests that can be performed to evaluate the patient while on mechanical ventilation. The sedation is usually weaned off every day to see if the patient will awaken. X-rays are usually taken daily to compare from one day to the next. Arterial blood gas samples are taken to examine blood pH, carbon dioxide, and oxygen levels. The physical tests are done during the “sedation vacation” (daily weaning from sedation). Weaning parameters can also be performed by the respiratory therapist. The parameters that are checked are the patients’ tidal volume, respiratory rate, and minute ventilation along with the patient’s ability to take a deep breath. The rapid shallow breathing index (RSBI) is also checked during the weaning parameters, this is a calculation of the patients’ respiratory rate divided by the tidal volume (in Liters). The RSBI is a useful tool in predicting successful extubation (removal of the breathing tube).
Placement on a mechanical ventilator can be an emotional situation for the patient and the patient’s family. The patient will be well taken care of while in the intensive care setting and it is important to realize that well trained individuals are taking care of the patient. Occasionally, it takes time to successfully remove a patient from the ventilator. It is better to be patient with the hospital staff and physicians working with the patient, removing a patient from mechanical ventilation too early can lead to re-intubation and subsequent days on the ventilator.