The control of the vital functions is an essential part of the diagnostic block as part of the emergency life-saving measures . A disturbance of the vital functions leads to an insufficient supply of the brain with oxygen , whereby there is a risk of brain death . All first aid measures in the event of an emergency are aimed at securing the vital functions or, in the case of cardiopulmonary resuscitation, on their artificial replacement. In addition to the immediate measures, the rapid calling ( emergency call ) of the rescue service including the emergency doctor is crucial.
The determination of vital signs has historically been an important diagnostic aid, especially when it is unclear whether a patient who has been seriously ill for a long time has actually died. In particular, these were the following symptoms :
- a fogging mirror in front of your mouth and nose (moist air you breathe)
- Movement of lather on the lips or nostrils (breathing movements)
- Up to half an hour after intravenous injection of a fluorescein solution under quartz light, the conjunctiva or mucous membrane is characteristically luminous (blood circulation is still reasonably functioning)
- bleeding (bloodstream) caused by an injury to a congestive vein or a pinched finger
- arteries of the retina that can still be seen during an ophthalmoscope (continued blood flow due to blood circulation)
- persistent reflexes (especially corneal and pupillary reflex )
- the non-adjustment of the body temperature to the ambient temperature (metabolism, circulation)
- if the skin is more irritated, blistering or reddening (metabolism, nerve activity)
- Rashes on the electrocardiogram or electroencephalogram (continued cardiac excitation or brain activity)
Nowadays rescue personnel are obliged not to lose any time checking for any positive signs of life and to assume that the person is still alive until certain signs of death appear and to undertake appropriate resuscitation attempts.