Brief Answer:
it depends...

Detailed Answer:
Hello,

regarding the blood pressure medication the answer is easy. She can be off the drug for as long as her blood pressure is OK.

The blood thinner discontinuation is not as easy to decide though. I suppose she's taking it for atrial fibrillation, right? If she takes it for other disorders then please let me know because the answer may be different...
Atrial fibrillation may cause the formation of blood clots in the heart and these clots may occlude peripheral arteries causing stroke and other serious disorders. Fortunately this is not a frequent event. Taking blood thinners causes increased tendency to bleed and the bleeding may go on for long.

Some blood thinners like low molecular weight heparins (LMWH) are safer to use because their effect wears off in a few hours but they may cause problem to the platelets, so patients with low platelet counts cannot take them. The rest of blood thinners are less safe and can't be used when the patient is bleeding.

So the real question is: which is the greater danger for your mother? Bleeding or thrombosis? Her doctors obviously decided that bleeding was the immediate concern. Being off blood thinners raises concerns about thrombotic events but bleeding may cause serious problems to her immediately.

Finally regarding side effects of antihypertensives: you can't say which drug has the least side effects because every single drug has a lot of them. It's a matter of luck which side effect (if any) will occur. We usually decide about the 'best' drug based on the patient's history. For example a patient with type 2 diabetes and proteinuria will be better off with an angiotensin receptor blocker than a beta blocker or diuretic.

I hope I've helped you to understand the reasoning behind such decisions.
Please contact me again, if you'd like any clarification or further information.

Kind Regards!

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