Farmakologi:
·
Normally about 80
to 90% of the potassium intake is excreted in the urine, the remainder in the
stools and to a small extent, in the perspiration. The kidney does not conserve
potassium well so that during fasting, or in patients on a potassium free diet,
potassium loss from the body continues resulting in potassium depletion. A
deficiency of either potassium or chloride will lead to a deficit of the other.
Apabila melibatkan garam/elektrolit, unit yang digunakan
adalah 'milimol @ mmol' bukannya 'gram @ miligram'. Saya bagi contoh :
a) 1
g Mist@Mixture Potassium Chloride (KCl) adalah bersamaan 13.4 mmol. Kebanyakan penyediaan larutan air KCl 1 g
adalah bersamaan 15 mL.
Berapa banyak mmol K di dalam setiap penyediaan ubat
gantian potassium (yang terdapat di fasiliti KKM)?
a) Mixture KCl 1g = 13.4 mmol
b) Tablet KCl 600mg = 8 mmol
c) Injection KCl 1g/10ml = 13.4 mmol
d) Injection Potassium Dihydrogenase Phosphate (KH2PO4) =
10 mmol (digunakan untuk merawat kekurangan Phosphate/PO4)
Apa Yang Bahaya Hypokalemia?
·
symptomatic cardiac arrythmias or conduction
disturbances (dengan melihat pada ECG), respiratory muscle weakness, paralaysis
Inj. KCl = High Alert Medication & Must Dilute Before
Use!
·
Injection Potassium Chloride (KCl) adalah salah
1 'High Alert Medication'. Pastikan anda menguruskan ubat tersebut dengan betul
mengikut protokol yang ada dalam 'Guideline on . Yang paling penting adalah
Injection KCl mesti di dilute sebelum digunakan. Maksudnya dilarutkan di dalam
dilution yang sesuai sebelum diberikan kepada pesakit, kebiasaannya 1g in 100cc
NS over 1 hour @ 1g diluted in 500mL NS/D5%
over 2 - 3 hours. Tetapi, kita preferred NS biasanya. Ini kerana 'Sodium chloride 0.9% may be the preferred
diluent in critical states, unless contraindicated, due to potential decrease
in serum potassium from glucose solutions'.
Kenapa Perlu
Dilute & Bagi Secara Infusion Inj. KCl?
·
If
potassium is administered too rapidly or if excretion is impaired, potentially
fatal hyperkalemia can result; it can develop rapidly and asymptomatically.
Therefore careful monitoring of serum potassium concentration and dosage
adjustment is recommended. The symptoms and signs of potassium intoxication
include paraesthesia of the extremities, flaccid paralysis, listlessness,
mental confusion, weakness and heaviness of the legs, fall in blood pressure,
cardiac arrhythmias and heart block. Hyperkalaemia may exhibit the following ECG
abnormalities: disappearance of the P wave, widening and slurring of the QRS
complex, changes in the ST segment, tall-peaked T-waves. Nausea, vomiting,
diarrhoea and abdominal discomfort have been reported
·
Too rapid
infusion of hypertonic solutions may cause local pain and, rarely, vein
irritation.
Adverse Reaction
Inj. KCl?
·
febrile response,
infection at the site of injection, venous thrombosis or phlebitis extending
from the site of injection, extravasation, hypervolemia, and hyperkalemia.
·
nausea, vomiting, abdominal pain and diarrhea.
Monitoring
Parameter?
·
Sudah
tentu Potassium level perlu dipantau sentiasa terutama apabila pesakit
diberikan Injection KCl sekurang-kurangnya setiap 24 jam.
Maximum Dose
Potassium? *with close K monitoring
·
Usually 200
mmol@mEg/day
·
Can go up to 400
mEq/day
Stability of Inj.
KCl?
·
Hanya 24
jam sahaja setelah dilute. Oleh itu, penyediaan melebihi 24 jam perlu dibuang.
NOTES:
1. Administer
supplements cautiously in patients with renal impairment and those on potassium
sparing diuretics (e.g. spironolactone) or ACE inhibitors (e.g. ramipril).
2. Magnesium
deficiency must be replaced to adequately restore potassium.
Disclaimer : Sila
rujuk ahli farmasi untuk kepastian. Blog ini hanyalah berkongsian pengalaman
yang dilalui oleh penulis.
No comments:
Post a Comment