Bicarb drip

[tomaquar]

We have a 86 yo demented female with probable urosepsis, Na 165, lactate 1, ph 7.20, bicarb 11 down from 16 yesterday. Blood gasses WNL.

 

Bicarb drip is my first thought but at what rate and do I take any special precautions for the Na?

 

Thanks

[tomaquar]

typo, ph 7.30 not 7.20

[andersenpa]

interesting

lactic acid 1 is not much of a source for metabolic acidosis to produce a pH of 7.30, so is there another source

Anion gap?

normal Co2 you say

 

typically bicarb infusion is reserved for ~7.20 or less

BUT

I will still give it as a push for ph in the 7.3 range if there is hemodynamic instability, myocardial dysfunction, coagulopathy, or CO2 offloading abnormality.

sounds like you have a dehydrated pt with a major free water deficit

volume resuscitation can do the trick to gradually restore renal Na/HCO3 handling and metabolize any organic acids you are dealing with

 

the gtt is usually prepared 150 meq/1000 ml D5W. The dextrose will rapidly metabolize giving you an iso-osmolar infusion

unfortunately....

the Na load from the bicarb will worsen your hypernatremia.

typically the high osmolarity will draw water to the ECF but if she is already dehydrated, she may not have much to give.

 

I would stick with normal isotonic or hypotonic fluid resuscitation (NS, 1/2 NS, or LR) depending on the severity of shock and follow chemistries. Bicarb could hurt you here.

[deborah212]

interesting

lactic acid 1 is not much of a source for metabolic acidosis to produce a pH of 7.30, so is there another source

Anion gap?

normal Co2 you say

typically bicarb infusion is reserved for ~7.20 or less

BUT

I will still give it as a push for ph in the 7.3 range if there is hemodynamic instability, myocardial dysfunction, coagulopathy, or CO2 offloading abnormality.

sounds like you have a dehydrated pt with a major free water deficit

volume resuscitation can do the trick to gradually restore renal Na/HCO3 handling and metabolize any organic acids you are dealing with

the gtt is usually prepared 150 meq/1000 ml D5W. The dextrose will rapidly metabolize giving you an iso-osmolar infusion

unfortunately....

the Na load from the bicarb will worsen your hypernatremia.

typically the high osmolarity will draw water to the ECF but if she is already dehydrated, she may not have much to give.

I would stick with normal isotonic or hypotonic fluid resuscitation (NS, 1/2 NS, or LR) depending on the severity of shock and follow chemistries. Bicarb could hurt you here.

Andersenpa.... for my own learning, is this a patient where for volume repletion giving LR might be optimal assuming that she isn't is multi-organ failure? A sodium of 130 will help slowly correct her free water deficit (may need D5W if not effective) and the lactate will be metabolized into bicarbonate through the liver.

 

What's her Cr doing? It seems like she may not be reabsorbing bicarbonate from an RTA. Do you have her full set of electrolytes, ABG, and urine studies?

[andersenpa]

Andersenpa.... for my own learning, is this a patient where for volume repletion giving LR might be optimal assuming that she isn't is multi-organ failure? A sodium of 130 will help slowly correct her free water deficit (may need D5W if not effective) and the lactate will be metabolized into bicarbonate through the liver.

 

What's her Cr doing? It seems like she may not be reabsorbing bicarbonate from an RTA. Do you have her full set of electrolytes, ABG, and urine studies?

 

It depends on the renal function- hopefully the OP will respond, we don't know if she has ARF or not. If so, even though the K content of LR is low I avoid it if hyperkalemia and worsening acidosis is the problem. If her kidneys are fine then I think it might be splitting hairs between LR and NS. Anything to improve the prerenal component and get her nephrons perfused. BUT...always better to give more free water in such severe hyperNa. Either way, restore her ECFV, and there should be less Na retention (dec RAA axis) and a general washout/metabolism of the acids.

 

IF it is a nongap acidosis (RTA as you said) then bicarb may be in order. I have rarely if ever dealt with RTA so who knows!

 

w/ a dx or urosepsis she may have glomerular dysfunction. curious as well to know the rest of the chem panel, if urine lytes/pH were done....

[tomaquar]

Ill post the labs tomorrow. I turned it over to a renal consult.

 

We have been giving her D5 for a few days so the dehydration should be taken care of. It was just yesterday that her bicarb stated to fall. She has been hypotensive but nothing severe so I dont THINK its AKI but Ill let you know what renal says on that one.

 

The only time I run bicarb in D5 is with a septic code and then its wide open. Is 3 amps per liter running at 100ml/hr appropriate for this setting ?

[rcdavis]

I am a little slow here. But without more numbers the question makes no sense. Simply replacing bicarbonate won't help ( and may worsen) whatever process is eating it in the first place. If you are simply looking to alkalinize the urine, or compensate for hyperkalemia, or nonorganic acidosis, andersen's ratios will do. reversingextracellular acidosis can worsen intracellular /mitochondrial ACIDOSIS via carbonic acid production. So, op, please post the metabolic profile of the PT, and you thoughts as to her volume status, and which organic cations/ solvents, or processes are involved in her CO2 defect, with a normal pH.

Help me understand your problem more fully, and I might ge able to help you tease out the answer