does everyone have dead space in their lungs

When a death is expected, the ideal place for it is at home, in a familiar environment, surrounded by family. I'm not saying that death is psychologically motivated, but there's a sense that people stay alive for these events and their loved ones, and then pass away, so the death rate increases on birthdays and during religious festivals.

People tend to hang on for a birthday or Christmas. Also, many people die on special occasions. This is because there are some terminal events, such as an enormous heart attack or clot on the lung, where the bodily sensation is as if you want to defecate. Most people will die in bed, but of the group that don't, the majority will die sitting on the lavatory. A forensic scientist can estimate the time of death by whether rigor mortis has come and gone. Rigor mortis is the stiffening of the body, which begins a few hours after death and then after a while starts to reverse. Those tests would be done before organ donation. Nowadays there are machine tests for brainstem death that involve connecting up the brain and looking at the activity. If you're not certain, you can rub on the breastbone, which is a very painful procedure: if they are not dead, they'll quickly jump up and say, 'That hurt!'

You examine for signs of breathing, you look at the pupils to check there is no response to a shining light. To certify that someone is dead, you listen to the heart for one minute and feel for a pulse for one minute. You can still have reflex actions, so you may twitch after death. If that bit of the brain is dead, then the person is essentially dead.

The brainstem is the part of the brain where the body's vital functions are controlled - the breathing, the heart, the brain itself it is the computer room of the body. What I'm essentially looking for is brainstem activity.

Does everyone have dead space in their lungs