Utilizing the 4 Dโs to exercise fluid stewardship
โPoison is in everything, and no thing is without poison. The dosage makes it either a poison or a remedy.โ -Paracelsus, date unknown
For patients in septic shock or those that are dehydrated, administration of fluid is top priority to restore adequate intravascular volume, increasing cardiac output, augment oxygen delivery, and improving tissue oxygenation.
However, fluid administration is not without side effects. Treating a patient with fluid will inevitably result in some degree of salt and water overload (fluid overload). This could result in a vicious cycle of interstitial edema, leading to organ dysfunction that contributes to more fluid accumulation (Manu et al, 2018).
In this blog, I will provide you with concepts to help you exercise fluid stewardship.
There are four important questions that need to be addressed in regards to fluid administration:
- What type of fluid?
- How much?
- How do we know when we have given enough fluid?
- How do we know when it is time to back down?
But first things first โ whatโs your goal: resuscitation or maintenance?
What is your indication for fluid management; that is, why are you giving your patient fluids? Are you trying to fluid resuscitate or just providing maintenance to keep up with their daily fluid requirement? Would free water flushes or taking free water po be enough? Do you think your patient is septic or have a condition where there is evidence of hypovolemia (dehydration due to diarrhea, vomiting)? In the urgent care setting or ED, most of the time, you are trying to fluid resuscitate them.
Fluids Are Drugs
Now think of fluid as a drug. In fact, fluid is a drug that you order to be administered. It is the most common drug that you order. We understand the concept of antibiotic stewardship. When prescribing antibiotic, we think about what we give, how much, for how long, and when the culture comes back, we would stop it or change the antibiotic accordingly. Likewise, if we apply the same mindset to fluid administration, we would consider the following:
- Drug – what type: Lactated ringers, Normosol, Plasmalyte, Normal saline, and varieties of saline (1/2NS, 1/4NS, etc), free water flushes. Do not give glucose containing solution for resuscitation.
Note: I prefer balanced crystalloids over NS (refer to SMART study, 2018)
- Dosage – how much: this goes back to what is the indication
The Patients Response
Also, think about your patientโs co-morbidities and how she/he may response to the amount of fluid that you are prescribing. If your patient has heart or renal failure, would a small amount of fluid at a time be more prudent than giving a liter or two in a short time? A patient with a normal LVEF may have diastolic dysfunction and cannot handle large amount of fluid. You can send them into diastolic heart failure.
- Duration – based on your indication, how long should you continue this fluid? Do you continue with NS or should you change to LR? Think about the effects of too much NS administration โ does hyperchloremic metabolic acidosis come to mind?
- De-escalation โ your patient is feeling better. He has started to take PO, or maybe he has started on tube feeding/TPN. Will this be enough fluid to meet his daily requirement? There are many triggers as to when to start fluid but no clear triggers to stop it.
Paracelsus is right โ no thing is without poison. How much we give will make it either a poison or a remedy. If we consider fluid as a drug, we have to apply clinical reasoning as to why we are giving fluid, what we are giving, how much to give, and when to stop giving. Fluid administration saves lives but if we do not exercise fluid stewardship, it can lead to fluid overload, tissue edema, and organ dysfunction. It is every providerโs responsibility.
References (abbreviated):
Manu, L.N.G. et al. (2018). Principles of fluid management and stewardship in septic shock: it is time to consider the four Dโs and the four phases of fluid therapy. Annals of Intensive Care. 8(66). Retrieved from annalsofintensivecare.springeropen.com
Semler, M.W. et al. (2018). Balanced crystalloids versus saline in critically ill adults. N Engl J Med. 378, 829-839.
Paracelsus quote. Retrieved from https://citatis.com/a4209/3306b/