2.3. Sedation Protocols

Horses received a CRI of medetomidine (M), medetomidine–ketamine (MK), medetomidine–morphine (MMo) and medetomidine–ketamine–morphine (MMoK) for two hours (Table 1). Infusion solutions were prepared by adding 5 mL of medetomidine (Sedastart^® 1 mg/mL, B. Braun VetCare SA, Barcelone, Spain) in all treatment groups, 4 mL of ketamine (Ketamidor^® 100 mg/mL, Richter Pharma AG, Wels, Austria) in MK and MMoK treatment groups, and 1.5 mL of morphine (Morfina B. Braun 2%^®, B. Braun Medical, Barcelone, Spain) in MMo and MMoK treatment groups to a 500 mL saline solution bottle (NaCl 0.9%, B. Braun, B. Braun VetCare SA, Barcelone, Spain). Before the addition of the drugs, the same volume of saline solution was discarded to have a final volume of 500 mL. All solutions were administered by an electronic infusion pump at 0.5 mL/kg/h (Infusomat^®, B. Braun Surgical, Barcelone, Spain). The order of the procedures was established randomly using computer software.

Bolus and CRI dosages of the four sedation protocols. M (medetomidine), K (ketamine), Mo (morphine), ml (milliliter), mg (milligram), µg (microgram), h (hour).