Dyshemoglobinemia: Methemoglobin and Carbon Monoxide Poisoning (ABG Interpretation - Lesson 19)

A discussion of the pathophysiology and etiology of methemoglobinemia and carbon monoxide poisoning, including a review of the structure and function of hemoglobin, and the basic principles behind pulse oximetry and co-oximetry.

[potassiumiodideki]

Commenting on this late, but you you have cleared up so many concepts for me that I have been trying unsuccessfully to understand since the beginning of medical school. Thank you! I have the utmost admiration for you and all the others who try to make fantastic medical education accessible to those all over the world.

[StrongMed]

Dr. Khan, I hope you enjoyed the video and thanks for the comment. You are right that I used the normal Aa gradient formula for patients on supplemental o2. The additional supp. O2 term, (50 x (FiO2 - 0.21)), ends up being 0, so it doesn't impact the final answer.

[Dazzletoad]

Beautiful video. I really learned a lot more on CO related complications.

Thank you for this contribution to the educational world 👍🏻

[Dakespeculiarprocure]

Great teacher you are!! Helped a whole lot for my studies.

[weitingLin]

thanks you! Dr.Eric! It solved a big confusion of me that why the new edition of Harrison have removed the algorithm which based on A-a gradient change. the last part of the explanation that there are no exact algorithm to make direct diagnosis with A-a gradient change because the mixed entities of the disease, explained why the new edition of the Harrison removed the table "Approach to patient with hypoxemia".

[sunving]

Thank you Dr Strong! It is good lecture, even went on review physiology of it. I can’t thank you enough.

[Lampian]

Great!! Dr Eric God bless you for sharing freely. You're really great teacher. Keep it up.

[gustavoarroyo]

Great research, thank you so much for share this, I needed to know how long can a person be exposed to carbon monoxide depending on concentration in the environment, this is really helpful for my design project, best regards from Bogotá, Colombia.

[StrongMed]

Gustavo, I'm very sorry, just seeing your question now. I'm afraid a quick literature search failed to find any information more specific than that presented in the video (around the 23rd min). You may need to consult a textbook on toxicology or emergency medicine.

[deebibi]

Thank you Dr.Eric this presentation helps me a lot for my finals...

[Psyxix]

Great lecture, this helped me a LOT! Glad I found your channel.

[Akhil-klct]

@Strong Medicine
How to check Methelmoglobin percentage in blood. How many test should be done ? I contacted with nitrate from that day problem started.

[helenewebster]

Very helpful in helping me understand my Late Mother's Iatrogenic Malfeasance manipulated Personal Injuries and foreseeable violent Death-Murder etc.

[sanbetski]

hello Dr. Eric, i love your channel and hope you keep it up. my question is @ 30:11. at step 1, how was the patients 60% FiO2 derived from a 10L facemask? if i use the formula fio2 = .21 + (.03 x O2 in lpm), i get a value of PAO2 318.63, instead of 383. thanks!

[superbesli]

How about upper zones of the lungs is normal but the left and right diagrams was absent. What should we think

[sujanpoudel]

Why in example 1, pt has normal gradient HYPOXEMIA since she has PaO2 of 340??

[aminkhan]

thanks but y u used suplemental oxygent Aa gradient age corected formula i think pts is on room air

[seddiqOutlaw]

Sorry for the misunderstanding but
C.O and Meth HB
- Won't allow O2 to off load at the tissues
- If C.O or meth molecule is already attached to HB then this will prevent O2 from binding onto the HB

[PantsEnthusiast]

This was incredibly helpful! Thankyou

[saikat]

Clues to the presence of methemoglobinaemia -Cyanosis despite normal SaO2.Sir i am little