electrolytes lecture by Dr F

writing this with api membara dalam hati.
but after all, disebabkan aku nak ilmu, semuanya harus ditempuhi dan dilupakan. whatever it is. me have to be kuat.

usually, everyday we'll lose 2500 mililiter of water(urine,sweat,respiration,faeces).
so, for patients who cannot tolerate orally, unconcious, dehydrated, we need to give them water through IV drip(ye kot) around that 2500ml jugak.

Important body electrolytes are sodium and potassium. Daily, we need 1-2 mmol/l perkg, per24hours of sodium and 1 mmol/l perkg per24hours potassium. (mostly potassium is inside cells and sodium is outside cells). Potassium will be lost only if we have trauma, when cells are damaged.

so normally we take standard weight : 70 kg. So what a patient need daily are :

1-2mmol sodium x 70kg = 70-140 mmol sodium
1 mmol potassium x 70 kg = 70 mmol potassium
2500 ml h20

a bottle of normal saline usually used in hospital contains :

150 mmol/l sodium
0 potassium

its content is actually 500ml, so actually it contains

75 mmol sodium

so how do we give patient enough sodium and saline?

if we use only normal saline, we could have give 2500 ml h20 using 5 bottles of ns, but then we will over saturate the patient with a 75x5 mmol of sodium which is (375mmol)- extracellular fluid (intravascular and interstitial) will be hypertonic, and cells (intracellular fluid will be hypotonic)will shrink to achieve osmolarity equlibrium. we dont want this.

how to give normal saline and sodium, perfectly as neede by patient?

we use other solutions, which is dextrose 5%(D5) solution. it contains glucose, no sodium nor potassium.

so, 2 bottles of ns will give :

150 mmol sodium
1000 h20

and plus 2 botlles of D5 will give :

1000 h20

which sums up to be :

150 mmol sodium
2000 h20

nearly what the patient need.

one other solution is ringer's lactate (hartmann) it contains electrolyte nearly the same like in plasma(ye ke???) bacaan dia aku lupa tapi lbh krg 131, 5,...xingt dah.

ok korg..tadi kita bagi 2 bottles of ns and 2 bottles of d5 kan...that makes it 4 bottles in 24 hours. so one bottle is given in 6 hours. we dont wanna give it faster nor slower than it should be, so the drop of water is counted/estimated so it is controlled for 1 bottle=6hours.

for patients with brain injury, to prevent brain edema, we give fluid that is hypertonic to intracellular fluid, to prevent water accumulation in cells.

and in cases of severe trauma/burns(ye ke?) there might be need for potassium.


lastly, i admire you Mr F coz u taught it in a very easy way. u are Dr Y the 2nd.