title: Motor response evaluation during brachial plexus block anesthesia: An ultrasonography aided study.
abstract: BACKGROUND
  The sparing of ulnar nerve often leads to the failure of the upper limb blockade. It has been claimed that local anesthetic injection at the site of stimulator evoked finger flexion response is associated with highest success rate of a successful block. The lower trunk stimulation of plexus should yield similar results as this trunk contributes significantly for median and ulnar nerves of hand and forearm.
  
  
  METHODS
  The patients with intact anatomical upper limb structures underwent (a) combined ultrasound (USG) assisted nerve stimulator evoked motor response evaluation or in (b) open brachial plexus trunk stimulation evaluations. The individual patient's lower trunk stimulation motor responses were documented.
  
  
  RESULTS
  When combined the results of both USG and open plexus groups, wrist flexion was seen in 52%, finger flexion in 61% and forearm pronation or twitches of anterior compartment in 48% of total subjects studied. These responses were noted either separately or in combinations.
  
  
  CONCLUSIONS
  We conclude other than finger flexion, the wrist flexion the forearm twitches, pronation and wrist adduction may be used for lower trunk blockade and thus for higher accuracy.
authors.affiliation: Department of Anaesthesiology, A J Institute of Medical Sciences, Kuntikana, Mangalore, India.
authors.forename: Thrivikrama Padur
authors.initials: TP
authors.lastname: Tantry
authors.affiliation: Department of Anaesthesiology, A J Institute of Medical Sciences, Kuntikana, Mangalore, India.
authors.forename: Reshma
authors.initials: R
authors.lastname: Koteshwar
authors.affiliation: Department of Anaesthesiology, A J Institute of Medical Sciences, Kuntikana, Mangalore, India.
authors.forename: Harish
authors.initials: H
authors.lastname: Karanth
authors.affiliation: Department of Anaesthesiology, A J Institute of Medical Sciences, Kuntikana, Mangalore, India.
authors.forename: Pramal
authors.initials: P
authors.lastname: Shetty
authors.affiliation: Department of Anaesthesiology, A J Institute of Medical Sciences, Kuntikana, Mangalore, India.
authors.forename: Vasanth
authors.initials: V
authors.lastname: Shetty
authors.affiliation: Department of Anaesthesiology, KVG Institute of Medical Sciences, Sullya, DK, Karnataka, India.
authors.forename: B G
authors.initials: BG
authors.lastname: Muralishankar
keywords: Brachial plexus anesthesia; motor response; nerve stimulation; nerve stimulator; supraclavicular; ultrasound