title: Assessment of long-term vasoplegia induced by brachial plexus block: a favorable effect for hemodialysis angioaccess surgery?
abstract: OBJECTIVE
  Loco-regional anesthesia, along with the neurosensitive inhibition causes arterial and venous vasodilatation, that could be of interest for vascular access surgery. We evaluated the long term vasoplegia persistence after brachial plexic block.
  
  
  METHODS
  Five patients submitted to brachial plexus block for an orthopedic procedure have been observed. Both radial arteries, that of the blocked arm and the opposite as a control, were analyzed by ultrasound examination, at time 0 and 360 minutes after anesthesia induction. All patients were treated with the same anesthesiologic protocol: axillary approach, use of an electroneurostimulator, injection 10 ml of ropivacain 7.5% + 10 ml of mepivacain 2%. The parameters evaluated from the arterial ultrasound flowmetry were: peak systolic velocity (PSV), end diastolic velocity (EDV) and resistance index (RI).
  
  
  RESULTS
  No modification of the arterial flow were observed in the control arm at 0 and 360'after block induction. The blocked arm instead showed a significant decrease of the resistive index, stable at 360 minutes.
  
  
  CONCLUSIONS
  The vasoplegia accompaning plexic block lasted 6 hours after anesthesia induction. Whereas this longstanding haemodynamic effect is beneficial for early patency of vascular access for hemodialysis, needs to be ascertained by further investigations.
authors.affiliation: Department of Clinical and Molecular Medicine, Sapienza University, Rome, Italy. n.pirozzi@tiscali.it
authors.forename: Nicola
authors.initials: N
authors.lastname: Pirozzi
authors.forename: Laura
authors.initials: L
authors.lastname: Pettorini
authors.forename: Jacopo
authors.initials: J
authors.lastname: Scrivano
authors.forename: Anna
authors.initials: A
authors.lastname: Giuliani
authors.forename: Matteo
authors.initials: M
authors.lastname: Baldinelli
authors.forename: Giorgio
authors.initials: G
authors.lastname: Punzo
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Pirozzi
authors.forename: Paolo
authors.initials: P
authors.lastname: Menè
mesh_terms: D000779:Anesthetics, Local / Q000009:adverse effects*; D001166:Arteriovenous Shunt, Surgical; D001783:Blood Flow Velocity / Q000187:drug effects; D001917:Brachial Plexus / Q000187:drug effects*; D006439:Hemodynamics / Q000187:drug effects*; D006801:Humans; D009407:Nerve Block / Q000009:adverse effects*; D017534:Radial Artery / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000503:physiopathology; D012039:Regional Blood Flow / Q000187:drug effects; D006435:Renal Dialysis; D013997:Time Factors; D018615:Ultrasonography, Doppler, Color; D014654:Vascular Patency / Q000187:drug effects; D014655:Vascular Resistance / Q000187:drug effects; D056987:Vasoplegia / Q000139:chemically induced* / Q000000981:diagnostic imaging / Q000503:physiopathology
chemical_list: D000779:Anesthetics, Local