Friend In Hospital, Visa About To Expire. What To Do?

I am writing this post on behalf of a friend who is currently in Chulalongkorn Hospital in Bangkok, recovering from major surgery. His visa expires next week, he is concerned about remaining legal, and is not sure what needs to be done to extend his visa without doing a visa run.
It is possible he will still be in hospital recovering when the visa expires while there is also a possibility he might have returned to his condo. At this stage no-one can be sure when he will leave hospital. But whether he is in hospital or back in his condo, he really doesnt feel he will be able to travel / make a visa run as recovery from surgery which took place forty-eight hours is expected to take some time.
He is self-employed, has a work permit and a multiple-entry non-immigrant B visa. He makes a visa run every 3 months. The visa itself i.e. the sticker in his passport, is valid until next year so no problem there, but his ninety days permission to stay i.e. the stamp he gets each time he enters the country is up next week. Normally he would do a visa run then and get another ninety days, but as explained, he doesnt feel he will be able to travel at this time.
If he is unable to travel, what are his options? Is it a matter of getting a letter from the doctor / hospital and sending someone to Chaeng Wattana to get an extension in his absence? Is this an option? Are there other / better options? Any advice would be much appreciated!