从candide里看到的,请问下at each effort

从candide里看到的,请问下at each effort
原句是：The next day,as he took a walk,he met a beggar all covered with scabs,his eyes diseased,the end of his nose eaten away,his mouth distorted,his teeth black,chocking in his throat,tormented with a violent cough,and spitting out a tooth at each effort.
最后一个词组.
能够具体一点吗？额因为我不知道确切的意思所以不知道哪个是对的额...