[The problem of performing medical procedures without informed consent in unconscious patients].

The principle of informed consent to invasive diagnostic or therapeutic procedures is not applicable in most patients suffering from consciousness disorders. As in other medical situations, German law assigns priority to the patient's autonomy and employs the concept of presumed will inferred from third-party (e.g. relatives) communications or deduced from a living will. While discussion concerning the validity of such advance directives is ongoing, their applicability needs to be checked carefully in every case. When the patient's attitude or wish however remains unclear or not discernible, in an emergency situation medical activities must be directed without loss of time towards damage reduction and life preservation under all circumstances ("guaranteed provision of medical attention"). In clinical practice, efforts to deduce the patient's will must relate to the urgency and invasiveness of the intended medical procedures. This paper describes the framework of current legal rules and important case decisions involved in the process of decision-making for patients unable to give informed consent. Any such decisions must be documented comprehensively in hospital records.