Several years ago I saw a story about a boy in the UK that had a brain tumor and his situation looked hopeless. I remember how I felt when I saw the news. I felt burdened for the boy as I am sure many did. I felt burdened to pray for the boy that I never met. I even went so far as to call the UK to some churches and ask them to pray. That burden in prayer stayed with me for a month. I did not see any updates and let it go.
A few years later I was working at Billy Graham ministries. I had forgotten about the boy until one day when I was reading a Christian magazine in the break room at work and saw the update. A surgeon in America heard about the boy and arranged to do a new procedure with a gamma ray scapel or something like that. The boy had the surgery and recovered and went on to be a normal school boy.
When we have those burdens to pray, we need to respond to them. We may not know why we have the burden. Sometimes we find out the results and sometimes we do not. There is one person who always knows the results and that is the one we pray to, God. Those burdens may stay with us for a while or for a short time, but they come from God who for some reason unknown to us chooses to work through our prayers. Our job is to PRAY and leave the results to God.