الحمد لله رب العالمين
والصلاة و السلام على رسول لله وعلى آله و صحبه و سلم

1. In surgery, to be specific, in dealing with electrolytes, there's something we call "The Rule of 40".

2. The rule describes important points to be considered in dealing with potassium. There are basically 4 items, which are;

i. Not more than 40 mmol added to 1 litre solution
ii. No faster than 40 mmol/hour (to be infused)
iii. Make sure its urine output is at least 40 ml/hour
iv. Maximum amount can be given is 4 x 40 mmol/day (=160 mmol/day)

3. Potassium is really important, as a slight mistake in dosage or rate of infusion/injection could be lethal.

4. Once a upon a time, not long ago, there was a dramatic mistake in an operation that led to the death of the patient. It was a high profile case, as I could find no article or news regarding the case. My professor, Prof Dr. Hala Ezzat told us last week. I doubted it at first, so then I asked another professor, Prof Dr. Nadia El-Sharqawy. She told us the same, it did happen.

5. On that odd day, the operating surgeon was asking for one injection of an antibiotic. It was a minor surgery by the way. Unfortunely, the nurse by mistake handed the doctor an injection of potassium chloride instead. The solution was injected, and that was it. The patient died on the spot! He got immediate cardiac arrest on diastole. (As far as I know, one ampoule of potassium contains 5 ml of potassium. Each ml contains 2 mmol) My Allah bless his soul...

6. What made the case more interesting is, the patient was the son of the Minister of Health of Egypt at that time, who is, until now, an internationally well known respectable surgeon!

7. That former minister is Prof. Ibrahim Gamil Badran. He is the one responsible for establishing one of the biggest medical scholls in surgery, and is known as the Father of Surgery in Egypt. You can see his profile here. http://www.ias-worldwide.org/profiles/prof99.htm

8. May this case be a great reminder for us, doctors-to-be, that potassium kills, if given in certain amount and certain rate. And the safe range is really small. Another electrolyte that also has to be taken into consideration as serious as potassium is Calcium.

9. Don't you(and me) ever get tired of mastering medicine. We deal with lives. A slight slip, and the patient dies. May Allah bless us...

و الحمد لله رب العالمين