Abstract
Background and Objectives: Dexmedetomidine has been shown to reduce the intraoperative requirement of anesthetic and analgesic agents. This prospective, observational study was designed to assess whether intraoperative infusion of dexmedetomidine provides effective intraoperative analgesia in thoracic surgeries carried out using one lung ventilation, and to elucidate its beneficial effects if any in terms of reducing the requirement for inhalational anesthetics intraoperatively, thereby maintaining the protective effects of hypoxic pulmonary vasoconstriction.
Methods: Sixty patients were randomly assigned to two groups. Group 1 (n=30) received a loading dose of dexmedetomidine 0.3µg/kg iv during induction of anesthesia, followed by a continuous infusion at a rate of 0.3µg/kg/hr continued upto two hours of the surgery. Group 2 (n=30) received a volume-matched bolus and infusion of saline (0.9% saline). For each case, heart rate, peripheral oxygen saturation, and mean arterial pressure were recorded intraoperatively at regular intervals. Total fentanyl consumption and isoflurane requirement were noted intraoperatively for both the groups.
Results: The groups were similar with respect to baseline characteristics, and distribution of study subjects. The mean fentanyl consumption and the volatile agent requirement to achieve a particular intraoperative BIS value were significantly higher in group 2 compared to group 1 (p 0.002 and p ˂0.001 respectively).
Conclusion: Dexmedetomidine infusion provides effective intraoperative analgesia and reduces the isoflurane requirement to achieve a particular depth of anesthesia during thoracic surgeries performed using one lung ventilation.
Key words: Dexmedetomidine, MAC, BIS, OLV, Thoracic surgeries, Analgesia
Protective effects of melatonin on lung damage associated with one-lung ventilation: An experimental study
