TXmed
Forum Captain
- 308
- 132
- 43
So ive been told dopamine does not work in septic shock (although ive seen it in other peoples protocols). I was wanting to know the patho as to why it doesnt work. As well as why levophed does work .
Dopamine in septic shock
- Thread starter TXmed
- Start date
CANMAN
Forum Asst. Chief
- 805
- 425
- 63
The major difference is how they go about increasing mean arterial pressure. Nor-Epi gives good vasoconstriction with little cardiac squeeze. So it has less effects on HR, stroke volume, and output. Obviously shock is defined as inadequate tissue perfusion. So increase HR, stroke volume, etc increases your myocardial and tissue demand. Thus Dopamine increase MAP by increasing heart rate and stroke volume. In studies it has been proven to have increased morbidity and mortality over Levophed. In a patient with severe shock and acidosis, Levo coupled with Vasopressin works great. Also keep in mine adequate fluid resus in sepsis is super important as well. At my system we guide our fluid resus off venous lactate levels via point of care testing but true septic shock patients will typically need at least 40ml/kg of fluid on-board as well.
OP
OP
TXmed
Forum Captain
- 308
- 132
- 43
Ok. But why does dopamine NOT work ?
Merck
Forum Lieutenant
- 137
- 9
- 18
Dopamine can work, it is just not usually the best choice. You get, as mentioned, some inotropic and chronotropic effects, but also some squeeze as the dosage increases. However, in general most patients in septic shock are already tachycardic. Given that levo has much less chronotropic effect it is generally a better choice. It provides the squeeze needed, but keep in mind what was said in that the patient needs to be volume replete.
teedubbyaw
Forum Deputy Chief
- 1,036
- 461
- 83
Who said it "doesn't" work?
- 4,513
- 3,239
- 113
It does work (raises the BP), though it's not uncommon for unacceptable increases in HR or dysrythmias to precede desirable improvements in perfusion.
Also, all of the adrenergic receptors demonstrate reduced sensitivity in the setting of acidemia. Some think that norepinephrine is less affected by low serum pH than dopamine is; I don't know if that is actually true but one of these things may be the rationale of those telling you "it doesn't work".
Last edited:
- 4,930
- 1,333
- 113
Most of what I've seen lately for vasopressor management in sepsis has norepi as the drug of choice for the reasons given above. What I have also seen is that if the patient is normotensive, you can use dopamine, but if the patient becomes hypotensive you would switch over to norepi. Probably the biggest thing driving the norepi choice in septic shock is that they noticed a greater number of adverse events (including death) when dopamine was used. Of course, that's not the only thing that needs to be done...
Dopamine does work. Whether or not it is the best inotrope/pressor to use is the better question. Evidence points towards it not being the best agent to use. See jrm818's references. So far in my (quite limited) experience in the ED as a resident, I have yet to see dopamine used. Norepinephrine is the only one I've seen so far. As a med student in the ICU I did see norepi, neo, and vasopressin pretty frequently. I did once have a patient on dobutamine (or maybe it was dopamine) on a general medical floor for treatment of decompensated heart failure.
- 9,736
- 1,174
- 113
If I remember correctly and I may be totally wrong, still looking for a source but one problem with dopamine is it causes pre-capillary sphincters to constrict, as well as the vasculature, and can actually reduce peripheral perfusion even though the numbers look better. Also it can cause tachy-dysrhythmias, as already stated and many of these patients are already tachycardic to begin with.
- 680
- 10
- 18
Think about where the different adrenergic receptors are located, and what medications would be most effective to stimulate those specific receptors.
Dopamine will work to stimulate vasoconstriction, however norepinephrine is a much more reliable and potent vasoconstrictor.
Also, dopamine converting to norepinephrine in a patient with acidosis is not as favorable as it is in the patient with normal blood pH. Increased hydrogen ion concentration is common in septic shock, ultimately diminishing the amount of dopamine that will become norepinephrine when administered.
These are just a few of the reasons off the top of my head.
Dopamine will work to stimulate vasoconstriction, however norepinephrine is a much more reliable and potent vasoconstrictor.
Also, dopamine converting to norepinephrine in a patient with acidosis is not as favorable as it is in the patient with normal blood pH. Increased hydrogen ion concentration is common in septic shock, ultimately diminishing the amount of dopamine that will become norepinephrine when administered.
These are just a few of the reasons off the top of my head.
tpchristifulli
Forum Crew Member
- 36
- 16
- 8
Dopamine gets converted to nor epi by the enzyme b-hydroxylase. Pts in severe sepsis have a hard time making this conversion. Levophed is pressor of choice because it doesn't need to be converted.
Brandon O
Puzzled by facies
- 1,718
- 337
- 83
I believe there is some chatter that peds tend to have more myocardial stunning in sepsis and therefore dopamine may still be a reasonable way to go for them. But otherwise it seems the only folks still starting with dopamine are the ones too used to it to have made the switch yet.
- 680
- 10
- 18
I think it is also worth mentioning that these infusions are not always an "either" "or" type situation.
It is not uncommon to utilize one, two, or even three different agents when treating severe sepsis refractory to volume resuscitation. I have routinely transferred patients who were on both dopamine and norepi, adjusting the rates for the two to achieve what I was looking for.
Also, spot on about the peds precautions Brandon. I will also mention that for neonatal sepsis, dobutamine was a go to for us generally starting out. But neonates are a whole different animal entirely...that's a completely different thread.
At any rate, understand what each agent is best for (increasing PVR, increasing inotropy, chronotropy, etc.) and tailor each of those specific medications to the parameters you are trying to achieve.
It is not uncommon to utilize one, two, or even three different agents when treating severe sepsis refractory to volume resuscitation. I have routinely transferred patients who were on both dopamine and norepi, adjusting the rates for the two to achieve what I was looking for.
Also, spot on about the peds precautions Brandon. I will also mention that for neonatal sepsis, dobutamine was a go to for us generally starting out. But neonates are a whole different animal entirely...that's a completely different thread.
At any rate, understand what each agent is best for (increasing PVR, increasing inotropy, chronotropy, etc.) and tailor each of those specific medications to the parameters you are trying to achieve.
18G
Paramedic
- 1,368
- 12
- 38
The latest Surviving Sepsis Guidelines list Levophed as the first choice vasopressor which is based on latest evidence.
A Few Points on Meds:
- Dopamine has both alpha and beta (inotropic & chronotropic) properties. So it squeezes vessels, increases heart contractility and HR
- Levophed and Neo are more beta (inotropic)
- Dopamine is not good for volume-related hypotension (remember, squeezing dry pipes = no good)
- Sepsis causes massive volume problems (dry pipes)
- Septic Pts are typically already tachy and their hearts are stressed
- Dopamine is a poor choice because of the volume depletion and already stressed heart
- Levophed and neosynephrine are the best choices because the increase MAP (which really is a good indicator of end-organ perfusion) without squeezing the vessels (to an extent) and without dramatically increasing HR (to an extent)
- Given that most ALS rigs don't have levo/neo, it makes sense to give volume, volume, volume
- 5,018
- 1,356
- 113
- 4,513
- 3,239
- 113
Actually, norepinephrine is less of an inotrope and more of a vasopressor than epinephrine. According to Stoelting, norepi has approximately the same beta activity as epinephrine (some sources say it has less), but about 3x the alpha activity.
Phenylephrine has no inotropic activity at all - it is a pure vasopressor.
Both norepinephrine and phenylephrine cause a net decrease in MAP, as they increase afterload more than stroke volume - especially phenylephrine.
ToPofTheGame
Forum Ride Along
- 2
- 0
- 1
Seems like some have already hit this on the head... Why is the pressure low=osmotic shift, rate / contraction increase ( chrono/ino) will capitate the pump ( can't force through or oncrease thtough rate volume that's not present) marked increased HR (chrono )in septic shock accelerates potassium dump and cardiac arrhythmia potentials... If there was no option... Bolus, Bolus, piggy Dope@ bare minimum and prepare to override pace since u won't be able to turn back... Better plan would be Neo!! or # 2 in my book high volume low dose Epi drip while watching those "T" waves w bicarbonate and cal chlor on hand...
...