Ketamine in the intensive care unit (ICU): Sedative effects, haemodynamics, and impact on clinical decision-making

Background: Providing and optimising sedation for critically ill patients on the Intensive Care Unit (ICU) is a fundamental aspect of critical care. It allows patients to tolerate invasive therapies and procedures while minimising pain, discomfort, and distress.
Despite international guidance aimed at improving outcomes, current sedation practices and agents are associated with significant detrimental effects that negatively impact both patients and the NHS. Ketamine may represent a useful novel sedative agent, providing benefits to mechanically ventilated critically ill patients, however; it is rarely used in routine practice.

Aim: The aim of this thesis is to explore the use of ketamine sedation for patients undergoing mechanical ventilation on ICU as part of complex intervention development.
Methods: A mix of methods were used to address five objectives, including: reviewing current evidence, exploring the views and experiences of healthcare professionals regarding current sedation practices, investigating the need and acceptability for ketamine sedation amongst both clinical staff and patients, identifying barriers and facilitators to implementation, and developing a protocol for a clinical feasibility study of a ketamine sedation intervention on ICU.

Results: The evidence currently supporting the use of ketamine sedation on ICU is lacking, and significant barriers to implementation exist. Careful planning of an intervention and stakeholder buy-in are key to successful introduction of a ketamine sedation study.

Conclusion: This thesis describes the development of the UK’s first prospective study of ketamine sedation for patients undergoing mechanical ventilation on ICU. The feasibility study, and the supporting work, provide new insights into how a ketamine-based sedation intervention might integrate into clinical practice and will inform future complex intervention design.