Background: Over-sedation has significant impact on intensive care resources and patient outcome. Recent protocols that constrain and/or interrupt sedation delivery have reduced resource utilisation but have not significantly addressed difficulties in agitation control. Thus, patient outcomes have not changed significantly. The primary objective of sedation delivery in critical care is to control patient agitation at a minimum sedation concentration. Thus, it is a balance between minimizing sedation delivery and managing acute, and sometimes quite significant, episodes of patient agitation. In particular, agitation episodes tend to be sudden, “spiky” or acute, while, for convenience, sedation delivery tends to be continuous. Hence, many current methods and therapeutics used to control patient agitation are not matched to what is demanded by patient behaviour. This review examines sedation management in critical illness and explores how new methods of sedation delivery and new therapeutics can offer advantages over accepted practice.

Methods: The current literature is reviewed and results summarized to compare and contrast differing approaches to sedation administration. In particular, emphasis is placed on randomized control trials (RCTs) in the past 5 years highlighting new and existing methods of employing well accepted, existing drug therapies. Over 30 such articles were found and their results summarized for analysis in terms of drug type, critical care unit type.

Results and Outcomes: There currently exists no common approach to sedation therapy delivery due to a lack of full understanding of the underlying dynamics (both pharmacological and physiological). In particular, despite a large range of therapeutics, the majority of studies (over 65%) focused on new drug types at the expense of the most commonly used therapeutics. Many studies were hard to compare due to different definitions or applications of patient agitation resulting in potentially very different outcomes for otherwise similar protocols. In addition, different target patient groups and very short term studies with no long-term outcomes also made further analysis difficult. As a result, sedation delivery is still very much a custom therapy, delivered individually to each patient, with great variability across patients and units.

Conclusions: The lack of an underlying framework or structure for sedation delivery that is based on a first principles approach to therapy should be a focal point for new research. Questions as to the underlying causes of patient agitation and the specific physiological and psychological goals of sedation delivery should be addressed to provide the foundation for consistent best practice methods. In particular, there is a desperate need for an objective, repeatable and entirely non-subjective approach to measuring or quantifying patient agitation before we can begin to develop a consensus on how best to treat or manage it.