Let me try to apply what I have learned with my reading. Earlier this week, our consultant emphasized the importance of choosing the right intravenous fluid for surgical patients; they may have been put on nothing per orem, have electrolyte deficiencies, and it is paramount that we know what effects our choices would make with regards to the patients’ condition.
Now, let us try deciding on preoperative fluid therapy. Let me use myself as an example. According to Schwartz Textbook of Surgery 10th edition, the formula in computing the volume for maintenance fluids is as follows:
For the first 0-10kg, give 100 ml/kg per day
For the next 10-20kg, give an additional 50 ml/kg per day
For weight >20kg, give an additional 20 ml/kg per day
The example given by the textbook using the formulas above is here below:
A 60-kg female would receive a total of 2300 ml of fluid daily:
1000 ml for the first 10 kg of body weight (10 kg x 100 ml/kg per day);
500 ml for the next 20 kg (10 kg x 50 ml/kg per day); and
800 ml for the last 40 kg (40 kg x 20 ml/kg per day)
Now, let’s say I weigh about 47kg:
I would receive a total of 2040 ml of fluid daily:
1000 ml for the first 10 kg of body weight (10 kg x 100 ml/kg per day);
500 ml for the next 10 kg of body weight (10 kg x 50 ml/kg per day); and
540 ml for the last 27 kg of body weight (27 kg x 20 ml/kg per day)
Also, according to the textbook, hypotonic solutions are used such as 5% dextrose in 0.45% sodium chloride at 100 ml/h as initial therapy. So, do I just use one bottle of IVF as initial therapy here or follow my daily fluid requirement of 2040 ml already?