<s>[INST] My niece had a tricuspid valve repair approximately one week ago. She was doing well and had been moved out of ICU. She suffered a cardiac arrest early Monday morning. The doctors are telling us she had prolonged down time of 25 minutes or more. They re in the process of evaluating her brain function. EEG showed almost constant seizure activity, which they re managing with medications . I thought after 6 minutes without oxygen , your organs would shut down. Her heart, kidney and other vital organs seem to be functioning properly but of course she has suffered from lack of oxygen to the brain. Does 25 minutes sound possible? [/INST] HIT hank for asking to ChatDoctorI really appreciate your concern for your niece, this could be post-operative event after the cardiac surgery in valvular heart disease such cardiac arrest is very likely, although this happens very rarely, but chances of this condition can be neglected, is she remained unconscious for a long time or breathless then the cerebral damage would be there, this is real medical situation, you need to talk to medical team, take care, and sorry for the condition. </s>