Before reviewing Dr. Weingart’s (to me) ultimate airway post, EMCrit RACC Podcast 216 – The Hemodynamically Neutral Intubation, I wanted to again review Podcast 104 – Laryngoscope as a Murder Weapon (LAMW) Series – Hemodynamic Kills August 5, 2013 by Dr. Scott Weingart.
So here are excerpts from Hemodynamic Kills:
There is a high risk of cardiac arrest when patient hypotensive before or during or after RSI.
Deal with it by Planning Ahead [And by using the ultimate techniques that Dr. Weingart discusses in Podcast 216]
If the patient is hypotensive before you start, it is not safe to intubate the patient unless you are absolutely forced to.
If the patient is not hypotensive but has a clinical condition that predisposes to hypotension then you should be planning ahead to do this intubation safely.
All sedatives, all induction agents will drop the blood pressure in shock.
[Even the ones that don’t intrinsically drop the pressure will drop the pressure in patients with a high intrinsic sympathetic drive by relieving some of the patient’s appropriate anxiety.]
[And by intubating the patient you change him or her from negative pressure ventilation which augments venous return and hence cardiac output to positive pressure ventilation which decreases venous return and decreases cardiac output.]
The [induction] agent doesn’t matter as much if you dose it properly.
[If you are using something like propofol which really reduces cardiac output, the dose should be markedly reduced (although Dr. Weingart is just using this as an example – propofol would not be the best choice in the hemodynamically unstable patient).]
You can use propofol [if it’s all you have] if you reduce the dose by 90% [although there is no reason to use an intrinsically vasodilatory drug if you have a choice].
Etomidate is considered by many to be the ideal agent for intubating the hemodynamically unstable patient. It is not a horrible agent. It is not my choice. And the reasons for that are a couple of things: [Discusses the steroid suppression controversy but is basically okay with using it.]
Etomidate has supposedly flat hemodynamics. There is no intrinsic effect but it is going to take away the patient’s intrinsic sympathetic response because you are chilling them out. And you’re going to have all of the problems of converting from negative pressure to positive pressure. You can absolutely drop the pressure from etomidate but not intrinsically from the drug.
[However, you can’t reduce the dose of etomidate to get the same brain level in the shock patient – you have to use the same dose and that isn’t good. The video has a chart at 12:26.]
I need to use full dose etomidate [to get any decrease in their awareness – bad.] And now I don’t really know what a half dose of etomidate is going to do to a patient. And it has no analgesic effect so now if I suboptimely dose, they are going to have pain and they may have memory. I don’t like that.
So I don’t use etomidate for intubating the hemodynamically unstable patient.
Start at 13:01
(1) EMCrit RACC Podcast 216 – The Hemodynamically Neutral Intubation
January 22, 2018 by Dr. Scott Weingart
(2) Best Single Airway Podcast And Show Notes – “Airway Pitfalls” From EMC 110 And Drs. Helman And Winegart Posted on May 28, 2018 by Tom Wade MD
(3) Podcast 104 – Laryngoscope as a Murder Weapon (LAMW) Series – Hemodynamic Kills August 5, 2013 by Scott Weingart
(4) Podcast 173 – LaMW – Oxygenation Kills Part I
May 2, 2016 by Scott Weingart
(5) Podcast 3 – Laryngoscope as a Murder Weapon (LAMW) Series – Ventilatory Kills – Intubating the patient with Severe Metabolic Acidosis
May 22, 2009 by Scott Weingart
(6) Podcast 181 – Pulmonary Hypertension and Right Ventricular Failure with Dr. Susan Wilcox [link is to the shownotes and podcast].