The ethical and clinical importance of measuring consciousness in continuously sedated patients

Continuous sedation at the end-of-life is a practice that has attracted much attention. An increasing number of guidelines on the proposed correct performance of the practice have been drafted. All guidelines stress the importance of using sedation proportionally to the severity of the symptoms the patient is suffering from, and thus to reduce the patient’s consciousness no more than is absolutely necessary. As different patients can have different experiences of suffering, the amount of suffering should, ideally, be assessed subjectively; i.e. via communication with the patient. However, continuously sedated patients are often unable to communicate, making subjective methods of pain-assessment unusable. For these patients, the degree of consciousness is the sole available measure. It therefore seems important to adequately measure how deeply the patient is sedated, thereby allowing sedation to be increased where it is too light, and decreased where it is too heavy. This is in accordance with the idea that reducing consciousness is not an ethically neutral act. Although consciousness measuring techniques are a hot topic in anesthesiology, almost no research exists that looks at the use of such techniques in the context of continuous sedation at the end of life. This paper aims to review existing techniques to measure consciousness and to evaluate their applicability, efficiency and invasiveness for patients who are continuously sedated until death. Techniques commonly used to assess the depth of sedation in a continuously sedated patient are basic clinical assessment and sedation scales, and these techniques are often considered reliable and non-invasive. However, these techniques might not be very reliable since it is known that some patients are non-responsive and yet aware. Moreover, sedation scales require stimulation of the patient (e.g. prodding, shaking, or providing painful stimuli) and can thus be considered invasive of, for example, one’s bodily integrity or dignity. Other techniques, such as EEG derivatives, may score better on reliability and invasiveness. Yet these have so far never been compared to sedation scale scores for patients receiving continuous sedation at the end of life. Therefore, we conclude that, for both clinical and ethical reasons, research into the efficiency and applicability of other techniques, such as EEG derivatives, is urgently needed.

Jaar van publicatie:2014

Toegankelijkheid:Closed