Mainstream or Sidestream – There are various types of CO2 sampling technologies available. It is important to understand the difference between the applications in order to help you select the best option to satisfy your specific clinical requirements.

Mainstream CO2 Technology

With mainstream CO2 technologies, the CO2 sensor is placed on an airway adapter which is directly in the breathing circuit. As a patient breathes or is ventilated, the sensor analyzes the gas passing through the adapter and reports the CO2 values.

Mainstream technology is the ideal choice for intubated patients. The benefits of this type of technology are that the
measurement is made immediately at the airway. There is no sample removed from the breathing circuit.

What is the limitation of mainstream?
Because mainstream technology requires the insertion of an airway adapter into a breathing circuit, the sensor is vulnerable to breakage. Chances of dropping or hitting the side of the operating table on disconnection is greatly increased.

Sidestream CO2 Technology
Sidestream technology is the ideal choice for monitoring non–intubated patients.

The Sensor is located back up at the Monitor & measures by way of a Sampling Line.

What is the limitation of Sidestream?
Patients who require intubation and long– term ventilation typically will have thick secretions that are expelled.

Because Sidestream technology requires that the gas sample be transported from the breathing circuit, through the sample line to reach the CO2 analyzer, these secretions often will be aspirated into the sample line, causing the line to occlude requiring user intervention to correct the situation.

For Short–term Anaesthesia, we recommend Sidestream due to its Sensor Location & less chance of being damaged.

For Long–term Anaesthesia, we would recommend Mainstream, but remember this sensor needs to be treated carefully & special attention is required on Careful Disconnection from the Patient