"No meds in hospitals"

Recently i found myself in hospital with a heart attack, i had 3 stents inserted 10 years prior, I was told that i would need open heart surgery and was put on the waiting list.I had spent one week waiting for my op. I have had bi-polar for 35 years and take lithium every day. The first hospital in portsmouth which i was in had NO lithium which i thought was rather strange, anyway i was moved to southampton hospital for my triple by pass which went well, i was there for 2 weeks and guess what? they had no lithium too, suffice to say i started to get a little high , so much so they put a security guard outside my room for the duration of my visit. I find it strange that both hospitals in my area do not stock lithium, Is it expensive?are bi-polar people rare?. My mental health as you can imagine after major heart operation was not good and without my lithium ,well i was going up and down, i have recovered from the op now but im still struggling with my mental health and thats with my meds.