Additive Effects of Clonidine Used in Propofol Sedation in Colonoscopy

Colonoscopy is one of the most common procedures in the world, Colonoscopy is a procedure often performed for prevention, diagnosis, and treatment of a variety of symptoms and diseases of the lower digestive tract, and sedation or anesthesia should be considered as an important tool to increase its effectiveness. Sedation and analgesia are considered key components, as they reduce anxiety and discomfort and therefore improve the procedure tolerability and patient satisfaction, minimize risk of complications and provide better conditions for the examination. Propofol may be used alone or in combination with opioids and/or benzodiazepines. The use of propofol alone requires higher doses, which may lead to increased incidence of side effects. However, the risks and benefits of adding analgesic and sedative to propofol are controversial, and the selection of drugs is a crucial factor in determining the outcomes. Clonidine apparently produces its sedative and anaesthetic-sparing effects by stimulation of centrally located alpha2 adrenoceptors. Analgesia seems to be mediated mainly by activation of alpha2 adrenoceptors in the dorsal horn of the spinal cord.