Imminent

Impending; menacingly close at hand; threatening.

Imminent peril, for example, is danger that is certain, immediate, and impending, such as the type an individual might be in as a result of a serious illness or accident. The chance of the individual dying would be highly probable in such situation, as opposed to remote or contingent. For a gift causa mortis (Latin for "in anticipation of death") to be effective, the donor must be in imminent peril and must die as a result of it.