The purpose of the study is to evaluate how well the nasal spray can be used and if it helps prevent confusion in these patients. During the trial, some individuals will receive the insulin human spray, while others will receive a placebo containing sodium chloride. This comparison helps to determine if the medication has a real effect compared to a substance that does not contain the active medicine.

Participants in the study will be monitored during their stay in the intensive care unit, also known as the ICU, which is a specialized hospital area for patients requiring constant, close monitoring. The course of the study involves observing the patients after their surgery to check for any side effects, such as hypoglycaemia, which is a condition where blood sugar levels become too low, as well as tracking the severity and duration of any mental confusion.

Participants in the study will receive Dexmedetomidine through an intravenous infusion, which means it will be administered directly into a vein. The study will observe changes in brain activity and blood flow while participants are awake and under different levels of sedation caused by the medication. The study will also use electroencephalography (EEG), a method to record electrical activity of the brain, to gather more information about how the brain functions during these different states.

The study aims to gather data on how Dexmedetomidine affects brain signals and other bodily functions, such as blood pressure and heart rate. This information will help researchers understand the potential benefits and effects of the medication on brain health, particularly in relation to the diseases being studied. The study will also look at how the medication affects various biomarkers, which are substances in the body that can indicate how well the body is functioning or responding to treatment.

Participants in the study will receive either the inhaled Isoflurane or the intravenous sedation as part of their treatment while they are on mechanical ventilation. The study will monitor the occurrence of delirium and other outcomes such as the length of stay in intensive care, the need for additional medications, and the quality of sedation. The trial will also assess the impact on mortality rates and the number of days patients can live without mechanical ventilation.

In addition to Isoflurane, the study involves the use of other medications like Propofol and Sufentanil, which are commonly used for sedation and pain relief in intensive care settings. The trial aims to provide valuable insights into the best sedation practices for improving patient outcomes in intensive care units. The study is expected to continue until 2025, with recruitment starting in 2024.

The purpose of the study is to explore whether these medications can effectively prevent delirium in patients who are 70 years or older and are undergoing heart surgery with the use of a heart-lung machine. The study will involve administering the medications through an intravenous infusion, which means they will be given directly into a vein. The treatment period will last for a maximum of two days. Participants will be monitored for any changes in their mental status and overall health before and after the surgery.

Throughout the study, researchers will assess various factors, including the number of days participants experience delirium, the severity of delirium, and any changes in cognitive function. They will also look at the overall health status of participants over time. The study aims to provide valuable insights into the potential benefits of using these medications to improve recovery and mental health outcomes after heart surgery.