Vet Med: How to Interpret a Capnograph

In this video I review the basics of capnography, including types of capnometers, how CO2 is produced, causes of hypo- and hypercapnia, phases of a capnograph, and common waveforms.
Please like and subscribe for more vet med videos!
/ @jenniferlyonsvts
/ jenniferlyonsvts
#vetmed #vettech #veterinarytechnician #VTSECC #capnography #capnometery #etco2 #ventilation

[@okiedokie8436]

Awesome review. Thank you so much!!!

[@jenniferlyonsvts]

Thank you!

[@brooklyn-kx4eh]

Love new videos!! ❤

[@jenniferlyonsvts]

Thank you so much!

[@smalls815ricardo8]

Hi Jennifer! Love your content! For capnometer readings that are too low or too high would you increase your PPV to about every 10-15 seconds until a more appropriate reading is obtained? Or could that potentially lead to over ventilating the patient?

[@jenniferlyonsvts]

Great question! It’s totally patient dependent and varies upon your baseline. So, if their CO2 is low, decreasing breaths per minute will drive it up. If their CO2 is high, increasing breaths per minute will drive it down. So you can try adjusting your breaths per minute by 2-5 in either direction and see if that helps.
Other things to asses for PPV are their breath size, and their inspiratory:expiratory ratio.

[@Maria0Tula]

Hey Jennifer. Love your videos. Just started following you. My question is, when inducing a patient and after intubation and the patient doesn’t wanna breathe how long do you wait before you give them a manual breath to determine if they’re gonna breathe on their own or not?

[@jenniferlyonsvts]

If you are performing ET tube cuff inflation checks (providing a positive pressure breath after induction to check the seal of your endotracheal tube) then the patient receives a breath immediately after being intubated. This also serves as an initial EtCO2 reading to confirm intubation. After that, I will usually provide a breath every 10-15 seconds in the stable apneic patient, although that rate varies based on my EtCO2 and disease process . A single dose of propofol lasts for about 5-10 minutes so if my patient is apenic I anticipate providing support for that period. And if they’re still not breathing by the time we’ve moved into the OR after prep, I would evaluate their anesthetic depth, and decide on the use of a ventilator.
I can’t find it now, but I read a study about induced apnea of dogs intubated and connected to an anesthetic circuit. They didn’t let the patient breathe and measured O2 and CO2 levels while still receiving a normal fresh gas flow rate. And it was something like close to an hour before their oxygen levels were affected, although the patients became severely hypercapneic. I think about that a lot now when I am supporting patients through the initial apneic period. Monitor EtCO2 and SpO2, and as long as those values are normal then your supported breath rate doesn’t need to be very aggressive.

[@rowanmorris2526]

Thanks for the useful info!! Also first comment is crazy

[@jenniferlyonsvts]

Thank you so much!

[@CristianAlvarado-s4l]

How does vasopressors mask Hypercapnia?

[@jenniferlyonsvts]

CO2 is a vasodilator and in high amounts can cause hemodynamic instability through cardiovascular depression. But in patients on vasopressors, who are stimulated to have vasoconstriction and increased cardiac output, these signs are masked. So, this comment really only makes sense for patients who are not having their EtCO2 measured. Sorry if I worded that in a confusing way!