title: Perioperative intravenous adenosine infusion to extend postoperative analgesia in brachial plexus block.
abstract: OBJECTIVE
  Adenosine infusions have been shown to reduce requirements of anaesthetics, to decrease the need for postoperative analgesics and to attenuate hyperaesthesia related to neuropathic pain. We decided to investigate the effects, beneficial or otherwise, of an adenosine infusion administered during surgery. A brachial plexus block was used to produce anaesthesia for the surgery.
  
  
  METHODS
  Sixty adults undergoing upper extremity surgery were included in the study. Brachial plexus block was performed via an axillary approach with lidocaine 1.25% and epinephrine 1/200 000 (40 mL). Patients were randomly assigned to two groups. During surgery, saline (control) or adenosine 80 microg kg min was infused intravenously in a double-blind fashion for 1 h. Visual analogue scores every 4 h, analgesic consumption, time to first spontaneous pain sensation, time to first rescue analgesic and adverse effects were noted during the first 24 h.
  
  
  RESULTS
  Vital signs were stable in both groups throughout surgery. During the adenosine infusion, one patient fainted while another complained of palpitations and tightness of the chest; both patients were excluded from further analyses. The time to first sensation of pain was significantly longer in the adenosine group compared to the control group (438 +/- 387 vs. 290 +/- 227 min, P = 0.02). The time to first rescue analgesic, the visual analogue scale scores and analgesic consumption in the postoperative period were similar.
  
  
  CONCLUSIONS
  In patients undergoing surgery with an axillary plexus block, a perioperative adenosine infusion prolongs the duration of postoperative analgesia to some extent. However, the time to first rescue analgesic, total analgesic requirements and pain scores were unchanged; the risk of potentially serious adverse effects is high. This therapy cannot be recommended.
authors.affiliation: Department of Anaesthesiology, Kirikkale University Faculty of Medicine, Kirikkale, Turkey. alpaslanapan@doctor.com
authors.forename: A
authors.initials: A
authors.lastname: Apan
authors.forename: S
authors.initials: S
authors.lastname: Ozcan
authors.forename: U
authors.initials: U
authors.lastname: Buyukkocak
authors.forename: O
authors.initials: O
authors.lastname: Anbarci
authors.forename: H
authors.initials: H
authors.lastname: Basar
mesh_terms: D000241:Adenosine / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000322:Adrenergic Agonists / Q000627:therapeutic use; D000328:Adult; D000700:Analgesics / Q000008:administration & dosage / Q000009:adverse effects / Q000627:therapeutic use*; D000704:Analysis of Variance; D000779:Anesthetics, Local / Q000627:therapeutic use; D001917:Brachial Plexus / Q000187:drug effects* / Q000502:physiology; D004311:Double-Blind Method; D004837:Epinephrine / Q000627:therapeutic use; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008012:Lidocaine / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D009407:Nerve Block; D010147:Pain Measurement; D010149:Postoperative Pain / Q000517:prevention & control*; D019990:Perioperative Care / Q000379:methods*; D011184:Postoperative Period; D013997:Time Factors; D016896:Treatment Outcome; D034941:Upper Extremity / Q000601:surgery
chemical_list: D000322:Adrenergic Agonists; D000700:Analgesics; D000779:Anesthetics, Local; D008012:Lidocaine; D000241:Adenosine; D004837:Epinephrine