how fit's you wife? 
O+ here, which i think means anyone can use it. i gave blood regularly back home but am not so sure out here. do they test it for things you might happen to imbibe on a KLM stopover?
O+ you are gifted

and if you help others by donating it then I Salute you!
Btw you need to be very careful about blood/urine tests if you ever mistakenly inhaled some of that stuff while on a KLM stopover, well to make it simple for you, anything like that in your blood stream even if it happened outside UAE you need not to go for any tests of any sorts, otherwise
You never know so better safe than sorry.
Also if youre clean then I recommend visiting Al Wasl Hospital for Blood donation, nice and quick.