Narrative:

About 1 hour into the flight; I was advised that an older passenger; mr X; was being given oxygen since he did not feel well. Mr X eventually fell asleep and everything seemed stable. Some time later we were advised that the passenger had gone to the bathroom and was not able to walk back to his seat on his own. Flight attendants requested if there was a doctor on board and 2 resident doctors volunteered their services. The doctors said the possibility that mr X had suffered a stroke became plausible. Dispatch was contacted and a medical conference call was made with a company contact doctor. From the physical description that was provided; it was determined that mr X most likely had suffered a stroke. I elected to divert to ZZZ and a medical emergency was declared and a clearance was requested by us to ZZZ center to proceed direct to ZZZ. 200 mi from ZZZ; we descended to FL290 and proceeded to jettison 19000 pounds of fuel to have us just below maximum landing weight in case an expedited turn was going to be considered for a possible re-dispatch. A visual approach was made at ZZZ and we proceeded to the gate where mr X and his family were taken off the flight as the passenger remained in their seats. The chief purser contacted the hospital the next day and she was told that mr X would have not survived this event if we had continued on to our destination.

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Original NASA ASRS Text

Title: B777 ENROUTE DIVERTS DUE TO PASSENGER SUFFERING A STROKE.

Narrative: ABOUT 1 HR INTO THE FLT; I WAS ADVISED THAT AN OLDER PAX; MR X; WAS BEING GIVEN OXYGEN SINCE HE DID NOT FEEL WELL. MR X EVENTUALLY FELL ASLEEP AND EVERYTHING SEEMED STABLE. SOME TIME LATER WE WERE ADVISED THAT THE PAX HAD GONE TO THE BATHROOM AND WAS NOT ABLE TO WALK BACK TO HIS SEAT ON HIS OWN. FLT ATTENDANTS REQUESTED IF THERE WAS A DOCTOR ON BOARD AND 2 RESIDENT DOCTORS VOLUNTEERED THEIR SVCS. THE DOCTORS SAID THE POSSIBILITY THAT MR X HAD SUFFERED A STROKE BECAME PLAUSIBLE. DISPATCH WAS CONTACTED AND A MEDICAL CONFERENCE CALL WAS MADE WITH A COMPANY CONTACT DOCTOR. FROM THE PHYSICAL DESCRIPTION THAT WAS PROVIDED; IT WAS DETERMINED THAT MR X MOST LIKELY HAD SUFFERED A STROKE. I ELECTED TO DIVERT TO ZZZ AND A MEDICAL EMER WAS DECLARED AND A CLRNC WAS REQUESTED BY US TO ZZZ CTR TO PROCEED DIRECT TO ZZZ. 200 MI FROM ZZZ; WE DSNDED TO FL290 AND PROCEEDED TO JETTISON 19000 LBS OF FUEL TO HAVE US JUST BELOW MAX LNDG WT IN CASE AN EXPEDITED TURN WAS GOING TO BE CONSIDERED FOR A POSSIBLE RE-DISPATCH. A VISUAL APCH WAS MADE AT ZZZ AND WE PROCEEDED TO THE GATE WHERE MR X AND HIS FAMILY WERE TAKEN OFF THE FLT AS THE PAX REMAINED IN THEIR SEATS. THE CHIEF PURSER CONTACTED THE HOSPITAL THE NEXT DAY AND SHE WAS TOLD THAT MR X WOULD HAVE NOT SURVIVED THIS EVENT IF WE HAD CONTINUED ON TO OUR DEST.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.