title: Clonidine as an adjuvant in axillary brachial plexus block for below elbow orthopedic surgeries: A comparison between local and systemic administration.
abstract: BACKGROUND
  Axillary brachial plexus block for below elbow orthopedic surgery provides a safe and low-cost technique with the advantage of prolonged postoperative analgesia. Clonidine, with selective partial agonist activity on α2 adrenergic receptors, has significantly demonstrated its role in this regard as an adjuvant to local anesthetics. The current study compares the locally administered clonidine with systemically administered control group in terms of onset and duration of sensory block, motor block, and analgesia; hemodynamic variability; sedation; and other side effect profile.
  
  
  METHODS
  Seventy patients (ASA I or II) scheduled for below elbow orthopedic surgeries were randomly allocated in equal numbers to receive either 30 ml of 0.5% plain bupivacaine with 150 μg (1 ml) of inj. clonidine locally in the axillary sheath and 1 ml of normal saline (NS) subcutaneously (Group L) or 30 ml of 0.5% plain bupivacaine with 1 ml of NS locally and 150 μg (1 ml) of inj. clonidine subcutaneously (Group S). Standard monitoring of vital parameters was done. Duration of sensory and motor block, analgesia, hemodynamic changes, and any adverse effects were observed and recorded for different duration up to 24 h.
  
  
  RESULTS
  Duration of sensory block (625 ± 35 min), motor block (690 ± 38 min), and analgesia (930 ± 45 min) was significantly longer in Group L than in Group S [sensory block (480 ± 30 min), motor block (535 ± 25 min), and analgesia (720 ± 30 min)] (P < 0.05). Significant alteration of heart rate, systolic blood pressure and diastolic blood pressure, and mean arterial pressure in Group S was observed compared to Group L (P < 0.05). Side effects like nausea and vomiting were comparable, but highly significant sedation score (χ(2) = 47.75 and 49.51 at 120 and 240 min, respectively; P < 0.01) was observed between the two groups.
  
  
  CONCLUSIONS
  Compared to systemic administration, local clonidine as an adjuvant in axillary block resulted in significant prolongation of duration of sensory and motor blockade, and analgesia without any hemodynamic alteration, probably by locally mediated mechanism of action.
authors.affiliation: Department of Anaesthesiology Burdwan Medical College and Hospital, Burdwan, West Bengal, India.
authors.forename: Sumanta
authors.initials: S
authors.lastname: Ghoshmaulik
authors.affiliation: Department of Anaesthesiology Burdwan Medical College and Hospital, Burdwan, West Bengal, India.
authors.forename: Bikash
authors.initials: B
authors.lastname: Bisui
authors.affiliation: Department of Anaesthesiology Burdwan Medical College and Hospital, Burdwan, West Bengal, India.
authors.forename: Debasish
authors.initials: D
authors.lastname: Saha
authors.affiliation: Department of Anaesthesiology, Bankura Sammilani Medical College and Hospital, Bankura, West Bengal, India.
authors.forename: Sarbari
authors.initials: S
authors.lastname: Swaika
authors.affiliation: Department of Anaesthesiology Burdwan Medical College and Hospital, Burdwan, West Bengal, India.
authors.forename: Arun K
authors.initials: AK
authors.lastname: Ghosh
keywords: Adjuvant; axillary block; clonidine; local; systemic