3 Acid-base Imbalances and Rehydration Management Part:1

Transcript

Welcome! back to the Fluid Therapy lesson.

In the last class we have seen, what are the choices of the Fluid, how to calculate this Fluid deficit, and what are the roots of administration- namely the intravenous root and the parental therapy.

In this class, we are going to see about

• Acid-Base Imbalances and
• how to do Rehydration Management in various disorders.

Now we have got a thumb rule:

for maintenance requirement, we have got 50ml/kg/day

Maintenance requirement = 50ml/kg/day and

the Fluid requirement in liters, there is a formula, Fluid requirement in liters is equal to surface area multiplied 2L/square meter

Fluid requirements in Litres = surface area * 2L/sq.m

So far, we have been calculating the Fluid deficit using bodyweight, now we will have a comparison with the surface area of the body.

Now let us solve this, by taking an example:

Calculate the Fluid requirement in a 450 kg body weight?

Let us proceed, with how to calculate based upon the body weight and surface area.

This chart gives the conversion factor from kg to surface area and the fluid requirement.Again this last column is based upon the formula surface area multiplied by 2 liters.

so substituting this namely the 450 kg body weight, the surface area is 5.64 and the requirement is 11.28 liters, so fluid requirement based upon the surface area is 5.64 multiplied by 2, it is approximately 11.28 liters but if you take the same thing based upon the body weight, so bodyweight multiplied by 50 ml per kg, it will be best equal to 22.5 liters. so consider surface area given 11.28 liters, whereas body weight given 22.5 liters, consider there is a hundredfold increase from 10 kg to 1000 kg but there is only 20 fold increase if you are taking to the surface area.

So this is to stress there is a non-linear relationship between body weight and maintenance Fluid requirement. why this is being emphasized, as the bodyweight keeps on increasing maybe 900 or 1000 as it goes the more important is you have to concentrate on the Surface area.

Now we will see step-wise, how to deal with the Acid-base Imbalances in various disorders.

• The first ones are D-lactic acidosis, urinary tract diseases, SI(small intestines) triangulation, obstruction, and choking. so, the disorder is mainly the metabolic acidosis low bicarbonate (HCO3)and there is severe dehydration.
• So the treatment or the management is you have to give sodium bicarbonate initially followed by isotonic fluids or electrolytes.
• Here we are going to see what is the changes we encounter in Neonatal calf diarrhea: the changes are metabolic Acidosis, low sodium bicarbonate, there is severe dehydration, loss of sodium Na, and that is hyperkalemia.
• what is the treatment? The treatment is a mixture of isotonic saline, isotonic bicarbonate HCO3 and please add on 5% dextrose because there will be hypoglycemia in the calf. If you want to save the calf, please add on 10 grams of glucose per liter of water.

We have been discussing Isotonic sodium bicarbonate, how to get that, so use 5and ½ of ampoules of 10 ml each, so it makes about 155 ml, mix it in 845 ml of water, so this will become Isotonic sodium bicarbonate. This can be used wherever there is an Isotonic sodium bicarbonate requirement, you can use it intravenously.

A base deficit in calf, there is a thumb rule, if it is less than 1 week(<1 week), it is 10-15 milliequivalent per liter(10-15 mEq/l ), if it is more than 1 week(>1 week), the Base deficit is 15 to 20 milliequivalent per liter(15-20 mEq/l), kindly substitute this in the requirement of acid[1]base balance and you will get the result.

What is the acid-base balance or changes you encounter in RDA(right side displacement of amazon); impaction, torsion, vagal indigestion, Caecal dilatation, or Caecal torsion, the predominant change is metabolic Alkalosis, which is reduced chloride, and severe dehydration? And the Treatment: use of balanced electrolytes and high potassium with chloride and add on acidifying solution.

Let us see what is the acid-base changes in Intestinal obstruction; the predominant change is metabolic Alkalosis, which is reduced to chlorine and reduced potassium.

The Treatment: use balanced electrolyte, high potassium, and chloride with an acidifying solution. Acute diffuse peritonitis, the changes; Dehydration and slight metabolic Alkalosis,

Treatment: please use balanced electrolytes in heavy quantity.

Per acute mastitis; here we encounter severe dehydration, Mild electrolyte defect, hypercalcemia and if there is diarrhea you also encounter acidosis.

So the treatment will be balanced electrolytes for 24 to 48 hours.

Ruminal Alkalosis/Putrefaction; here you use oral acetic acid, please use a stomach tube or rumen tube, to pass on this acetic acid into the rumen.

So the percentage is 2.5%, use 1-2 liters orally for 2-3 days. In addition to that, you need to use sodium chlorate, a dextrose normal saline intravenous. For the Putrefaction, you use an oral antibiotic namely tetracycline at 20 milligrams per kg body weight for 2-3 days followed by cut transplantation. If it is very severe go for Rumenotomy.

We have been discussing the Hypertonic Saline solution. So let us consider how to prepare Hypertonic saline solution. So this is 3-7.5% sodium chloride(3-7.5% NaCl), prepare this percentage is, highly useful for hemorrhagic, septic, and endotoxic shock. Now, what is the rate? The rate is 3-5 ml per kg(3- 5ml/kg) intravenous, it produces a very good effect, but don’t forget to use Isotonic solutions following Hypertonic saline.

In the case of Ketosis, we are using dextrose, hypotonic dextrose 20/50%, in addition, we may be using Isoflupredone, what happens is, this Isoflupredone causes excretion of potassium and there is hypokalemia.

(showing the slide) In the next slide, now we can see the twist, the neck twist in the case of cattle which indicates hyperkalemia. So don’t forget if you are using Isoflupredone continuously so there will be hypokalemia and substitute this potassium so that the animal becomes normal. Hypokalemia, in such cases you need to supplement potassium, please administer potassium very slowly even slower than the calcium administration, the rate should be very slow.

The availability is 10 ml ampoules and this hypokalemia occurs, even during treatment for rumen lactacidosis, and

(showing the slide) This next slide also beautifully shows, how the neck is twisted that is very muscle becomes very weak animal becomes Recumbent.

The rate is 0.5 milliequivalents per kg per hour (0.5 mEq/Kg/hr), never increasing beyond this rate. So 1.15 percent potassium chloride(1.15% KCl) gives about 3.2 ml per kg per hour (3.2 ml/Kg/hr). So there is a Scott thumb rule, which is indicated in the table, where the first column is the Serum concentration of potassium, the second is how much milliequivalent of potassium you are going to dissolve in 500 ml of saline, and the last one is the rate ml/per/kg/hr.

• 1.15%KCl = 3.2ml/kg/hr
• = 0.5 mEq/kg/hr Serum concentration mEq/500ml ml/kg/hr

Kindly refer this Scott thumb rule and then you can determine the milligram or milliequivalent of potassium, to be dissolved in one sachet and you can control the speed using the last column. If you are going to increase the speed then there will be the death of the animal. In many cases we use dextrose, rapid infusion of dextrose causes hypophosphatemia so whether in your case of ketosis you may be using this, or as a nutrient supplement to get effective oxaloacetate you may be using dextrose.

In such cases so see that hyper positivity does not occur if it occurs, you have to supplement phosphorus. In this lesson, we have detailedly seen The acid-base imbalances and the electrolyte requirement in various disorders of ruminant. The important disease for disorder we have seen in this class. In the next class, we are going to see how to calculate the ml of bicarbonate required based upon the formula and the millimole of bicarbonate equal to 0.3 multiplied by body weight multiplied by base deficit, because that calculation is more important for field conditions.

Thank you!