Reference: Sharh ‘Umdatil-Fiqh – Tape No.4, Question No.30
Question: What is the preponderant opinion regarding the one who has been unconscious for more than three days; is he required to make up the prayers he has missed whilst he was unconscious?
Response: Three days is something easy, [so] yes he should make up the prayers. If, however, he remained unconscious for a long[er] period, like months, then he is not required to make up the prayers. If, however, it was [only] for a period of three days or less, then he should make up the prayers – because this is [something] easy [for him to do].