Stan's gold medal viva exam

Dec 5, 2020

Dive into the intricacies of cardiac output measurement and the fascinating mechanics of the pulmonary artery catheter. Discover the nuances of acid-base balance and how to interpret blood gases effectively. Stan shares insights on the role of albumin in acid-base theories, shunt mechanisms, and the alveolar gas equation. Explore the physiological responses to pain, the sympathetic stress response, and the nuances of MAC in anesthesia. Lastly, uncover the details of anaphylaxis treatment and the effects of various bronchodilators.

Ask episode

AI Snips

Chapters

Transcript

Episode notes

INSIGHT

Systematic Blood Gas Interpretation

Understand acid handling via buffering, compensation and renal correction to distinguish respiratory vs metabolic causes.
Use base excess, PaCO2 and bicarbonate sequentially when interpreting an arterial blood gas.

ADVICE

Quantify Shunt And Venous Admixture

Do learn shunt, physiological contributors and the venous admixture equation to quantify hypoxaemia.
Do use the alveolar gas equation to calculate end-capillary PO2 and include the FiO2 correction factor when needed.

ADVICE

Use RQ Logic Not Only Memory

Do memorise respiratory quotient values for macronutrients and how to derive RQ from molecule composition.
Do reason through formulas rather than rote recall when pressed during vivas.

Get the Snipd Podcast app to discover more snips from this episode

Get the app

By popular demand, here is the actual physiology and pharmacology viva that Stan was examined on for the part 1 ANZCA exam!

Please rate, post a review and subscribe!

Check out www.anaesthesiacollective.com and
sign up to the ABCs of Anaesthesia facebook group
and check you the ABCs of Anaesthesia YouTube channel for more content

Any questions please email Lahiruandstan@gmail.com

Some links and formulas!

How does it measure cardiac output?

Using thermodilution and utilisation of Stewart Hamilton’s equation of:

(Tb-Ti)*Volume*k/intergration of change in T

What is venous admixture?

Venous admixture is the amount of mixed venous blood that needs to be added to end-capillary blood to account for the difference seen in pO2 between arterial blood and end-capillary blood.

It is calculated using the equation:

Qs/Qt = Cc’O2 – CaO2 / Cc’O2 – CvO2

Alveolar gas equation.

PAO2 = FiO2 (Patm – PH2O) – pCO2/R

Is there anything else at the end?

Yes there is a correction factor (+F) which is FiO2 * pCO2 * (1-R)/R and this is normally less than 2mmHg.

O2 content = SaO2 * Hb * 1.34 (Huffner’s constant which ideally is 1.39) + pO2 * 0.003

the isoshunt diagram is figure 8 here:
https://erj.ersjournals.com/content/44/4/1023.figures-only

Please rate, post a review and subscribe!

Check out https://anaesthesiacollective.com/education/first-part-exam/ for general information and a collection of model answers

and
sign up to the ABCs of Anaesthesia facebook group https://www.facebook.com/groups/2082807131964430

and check out the ABCs of Anaesthesia YouTube channel for more content
https://www.youtube.com/c/ABCsofAnaesthesia

If you have any questions, please email Lahiruandstan@gmail.com

Disclaimer:

The information contained in this podcast is for medical practitioner education only. It is not and will not be relevant for the general public.

This contains general information about medical conditions and treatments. The information is not advice and should not be treated as such.

The medical information is provided “as is” without any representations or warranties, express or implied.

The presenter makes no representations or warranties in relation to the medical information on this video.

You must not rely on the information as an alternative to assessing and managing your patient with your treating team and consultant.

You should seek your own advice from your medical practitioner in relation to any of the topics discussed in this episode’

Medical information can change rapidly, and the author/s make all reasonable attempts to provide accurate information at the time of filming. There is no guarantee that the information will be accurate at the time of viewing

The information provided is within the scope of a specialist anaesthetist (FANZCA) working in Australia.

The information presented here does not represent the views of any hospital or ANZCA.

These podcasts are solely for training and education of medical practitioners, and are not an advertisement. They were not sponsored and offer no discounts, gifts or other inducements.

This disclaimer was created based on a Contractology template available at http://www.contractology.com.