Tools of the trade: Respironics LoFlo Sidestream CO2 Sensor

CO2 sensor and monitor

by Dr Kevin Cruickshank, Gold Coast Vet Surgery, Surfers Paradise, QLD

We have integrated this Respironics LoFlo end tidal CO2 monitor into our routine anaesthetic monitoring. It connects to our general anaesthetic vital signs monitor and measures CO2 in the expired air.

What’s good about it

It provides a much more sensitive measure of the respiration and the depth of the anaesthetic. While a pulse oximeter is the most economical way of measuring the amount of oxygen in the animal’s blood, it’s not very sensitive to changes. Measuring end-tidal CO2 is the gold standard in human and veterinary anaesthetic monitoring.

Providing safe and effective anaesthesia is always a combination of individual monitoring by a human and the results generated by a monitoring machine. By monitoring the end tidal CO2, problems with breathing can be picked easier and quicker than by any other method. The anaesthetic can then be adjusted accordingly.

The LoFlo unit can also be used to give an indication if CPR is successful because it measures how much oxygen is exchanged while you are actually resuscitating a patient.

The LoFlo doesn’t add any extra time when connecting the patient to the monitoring equipment. It’s non-invasive, operates in the background, and is easy to use and interpret.

What’s not so good

It’s quite an expensive piece of equipment compared to a pulse oximeter. However, we feel that monitoring anaesthetics is not an area where we are going to compromise.

It also adds to the equipment that’s attached to the endotracheal tube. We use the sidestream system that allows for the unit to be positioned away from the patient. There is also a mainstream version where the unit is close to the head of the patient. In that situation, there’s a higher chance of the equipment being damaged by falling off the table.

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