Nebulized Dexmedetomidine and Intravenous Ketamine Versus Nebulized Ketamine and Intravenous Dexmedetomidine to facilitate Awake Fiberoptic Nasotracheal Intubation in adult patients undergoing Oromaxillofacial surgeries - A randomized double blind study

Awake fiberoptic nasotracheal intubation is a preferred method for managing patients with anticipated difficult airways. The success of this procedure largely depends on the sedative and analgesic regimen, which must ensure the patient remains comfortable and cooperative while maintaining airway safety and reflex suppression during the procedure.Commonly used sedatives in AFOI include benzodiazepines, sevoflurane, remifentanil, ketamine, propofol, and dexmedetomidine.

Previously combination of drugs have been used for AFOI to counteract each others adverse effects. Dexmedetomidine, an  alpha 2 adrenoreceptor agonist, is an ideal choice for AFOI because it provides sedation, analgesia, and anxiolysis without significantly impairing respiratory function, which is essential for maintaining spontaneous breathing during the procedure. Additionally, dexmedetomidine can reduce salivation, which helps counteract the excessive salivation caused by ketamine during sedation.

A key advantage of dexmedetomidine is that it allows patients to remain easily arousable without agitation, unlike sedatives like propofol that may cause deeper sedation and respiratory suppression. This makes dexmedetomidine especially useful, as patients can be more easily engaged during the procedure without irritation. The relative sympatholysis achieved during dexmedetomidine infusions is an additional benefit in a procedure that may lead to elevations of heart rate and blood pressure. Nebulisation with dexmedetomidine compared to intravenous results in desirable degree of sedation and better tolerance of the procedure with adequate attenuation of the haemodynamic responses to intubation.

Ketamine, an NMDA receptor antagonist, provides both sedation and pain relief while stabilizing hemodynamics through its sympathomimetic effects, such as increasing heart rate and blood pressure. However, ketamine can also increase airway secretions, which can complicate the intubation process by making it harder to visualize the airway and increasing the risk of aspiration. Managing this side effect is crucial for a successful procedure.

Using ketamine and dexmedetomidine together offers a synergistic approach that addresses the limitations of each drug. While ketamine offers effective analgesia and sedation with sympathomimetic effects, dexmedetomidine helps control the increased secretions caused by ketamine and prevents the rise in heart rate and blood pressure that ketamine can induce. This combination leads to more stable hemodynamics, deeper sedation, and an easier intubation process.

In summary, combining ketamine and dexmedetomidine during awake fiber-optic intubation offers a balanced and effective approach to sedation and analgesia and we aim to compare different route combinations between them.