My guess is he developed some irritation from flying and forgot to take his contact lenses out as he dozed off.
Rector was attending a Sunday night game between the Yankees and Red Sox when he dozed off.
Summers often dozed off when others were speaking—even during a meeting of the Board of Overseers.
1640s, probably from a Scandinavian source (cf. Old Norse dusa "to doze," Danish døse "to make dull," Swedish dialectal dusa "to sleep"); related to Old English dysig "foolish" (see dizzy). May have existed in dialect earlier than attested date. Related: Dozed; dozing. As a noun, from 1731.