Summary:
Objective: To evaluate the combination of dexmedetomidine and ketamine for analgesic sedation.
Design: Prospective randomised clinical study.
Setting: Department of Anaesthesiology and Intensive Care, University Hospital.
Materials and methods: Patients scheduled for Dupuytren’s contracture repair under local anaesthesia were
randomly divided to groups C and D. Group D patients were administered an infusion of dexmedetomidine
1 μg . ml-1 and ketamine 1 mg . ml-1 in normal saline as follows: 10 minutes before surgery a bolus of
0.04 ml . kg-1 (e. g. dexmedetomidine 0.04 μg . kg-1, ketamine 0.04 mg . kg-1) was given, followed by infusion
of 2 ml . kg-1. h-1 for the first 10 minutes (dexmedetomidine 2 μg . kg-1 . h-1, ketamine 2 mg . kg-1 . h-1) and
1 ml . kg-1 . h-1 (dexmedetomidine 1 μg . kg-1 . h-1, ketamine 1 mg . kg-1 . h.-1) for the rest of surgery. Group C
patients were given normal saline. Vital functions, analgesia and Ramsay score were measured.
Results: There were 7 patients in group C and 8 patients in group D. The demographic characteristics were
comparable between the groups. We found differences between groups C and D in Ramsay score (all group
C patients scored 1 point vs. 7 group D patients scored 2 points and one patient scored 3 points, p < 0.001),
absence of reaction to painful application of local anaesthetic and tourniquet (0 vs. 6, p = 0.02), amnesia
(0 vs. 6, p = 0.02) and light-headedness 1 hour after surgery (0 vs. 7, p = 0.005). Five patients in group D
remembered dreams (NS). There was a slight fall in blood pressure (25–30% below base-line) in 4 patients
in group D (NS) and no change in ventilation.
Conclusions: The combination of dexmedetomidine and ketamine provides analgesia, amnesia and catatonia
with preserved cooperation, and has no respiratory effects.
Key words:
analgesic sedation – dexmedetomidine – ketamine
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