[From the vegetative state to unresponsive wakefulness: a historical review]

Over the last few decades, the terminology, diagnostic techniques and treatment of patients with altered levels of consciousness have varied considerably. At the same time, the percentage of patients in this clinical situation has undergone a marked increase.

The purpose of this study is to present a historical review of the different terms that have been used in the medical literature to describe patients with altered states of consciousness. The article also includes the different diagnostic criteria utilised by research groups that have focused their attention on this population.

The concept of 'vegetative state', a term coined back in the sixties, has since been transformed and replaced by other terms with a less negative connotation, such as 'unresponsive wakefulness syndrome'. In parallel, new clinical categories (minimally conscious state or minimally conscious plus) have appeared since it has been acknowledged that there are patients with a low level of consciousness but who nevertheless show signs that are consistent with interaction with the environment by means of unmistakeably voluntary behaviours in response to orders or gestures.

The wide spectrum of signs and symptoms shown by patients with altered levels of consciousness reflects the clinical and neuropathological heterogeneity of these states. The current tendency is to describe the state clinically, adding the aetiology and the date of the event that caused the clinical picture. This article focuses on the context of an effort made by the scientific community to highlight the needs of this growing population.