Isabella weighs 22 kg and is approximately 10% dehydrated. How much fluid will she need over the next 24-48 hours in order to replace her current fluid deficit?"

She will require 2440ml over the next 24-48 hours in order to replace her current fluid deficit.

Explanation:

Let's picture Isabella's body as a big bag of water.

Recall:

1 gram of water = 1 mL of water;

while, 1 kg of water = 1 liter of water.

Therefore,

If Isabella current weight = 22 kg

Her rate of dehydration =10%

Pre-illness weight can be estimated using the formula:

Pre-illness weight

= Current weight

[(100 - % dehydrated) x 0.01]

= 22

[(100-10) x 0.01]

= 24.44 kg.

Thus, Isabella pre-illness weight = 24.44 kg

Deficit can be calculated for using the formula,

Deficit = pre-illness weight - current weight

= 24.44 kg - 22 kg

= 2.44 kg of body weight

Note that 2.44 kg is equivalent to 2440 mL

Therefore,

2440ml is estimated as free water deficit.

In most scenarios, the fluid composition and the time period over which it is given relies on the serum sodium levels and osmolarity. In DKA, the deficit is replenished evenly over 48 hours secondary to the hyperosmolarity.