Reference: http://www.alfawzan.af.org.sa/node/15367
Question: O Noble Shaykh, regarding someone who is afflicted with the persistent passing of wind, how should he pray?
Response: He should perform wudhoo [at the time] when he intends to pray; he should then pray [right away] as he is – even if he breaks wind [before or during the prayer], and his prayer is valid [in shaa.-Allaah]. That is because he is unable to do more than that, since this [condition renders him in a state of] permanent impurity – just like the condition of incontinence and that which is similar.