title: Feasibility of a 'reversed' isolated forearm technique by regional antagonization of rocuronium-induced neuromuscular block: a pilot study.
abstract: BACKGROUND
  The isolated forearm technique is used to monitor intraoperative awareness. However, this technique cannot be applied to patients who must be kept deeply paralysed for >1h, because the tourniquet preventing the neuromuscular blocking agent from paralysing the forearm must be deflated from time to time. To overcome this problem, we tested the feasibility of a 'reversed' isolated forearm technique.
  
  
  METHODS
  Patients received rocuronium 0.6 mg kg(-1) i.v. to achieve muscle paralysis. A tourniquet was then inflated around one upper arm to prevent further blood supply to the forearm. Sugammadex was injected into a vein of this isolated forearm to antagonize muscle paralysis regionally. A dose titration of sugammadex to antagonize muscle paralysis in the isolated forearm was performed in 10 patients, and the effects of the selected dose were observed in 10 additional patients.
  
  
  RESULTS
  The sugammadex dose required to antagonize muscle paralysis in the isolated forearm was 0.03 mg kg(-1) in 30 ml of 0.9% saline. Muscle paralysis was antagonized in the isolated forearm within 3.2 min in nine of 10 patients; the rest of the patients' bodies remained paralysed. Releasing the tourniquet 15 min later did not affect the train-of-four count in the isolated forearm but significantly increased the train-of-four count in the other arm by 7%.
  
  
  CONCLUSIONS
  Regional antagonization of rocuronium-induced muscle paralysis using a sugammadex dose of 0.03 mg kg(-1) injected into an isolated forearm was feasible and did not have relevant systemic effects.
  
  
  BACKGROUND
  The trial was registered at EudraCT (ref. no. 2013-002164-53) before patient enrolment began.
authors.affiliation: Department of General Anaesthesia and Intensive Care Medicine thomas.hamp@meduniwien.ac.at.
authors.forename: T
authors.initials: T
authors.lastname: Hamp
authors.affiliation: Department of General Anaesthesia and Intensive Care Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Mairweck
authors.affiliation: Department of General Anaesthesia and Intensive Care Medicine.
authors.forename: J
authors.initials: J
authors.lastname: Schiefer
authors.affiliation: Department of General Anaesthesia and Intensive Care Medicine.
authors.forename: M
authors.initials: M
authors.lastname: Krammel
authors.affiliation: Centre for Medical Statistics, Informatics, and Intelligent Systems, Section for Medical Statistics.
authors.forename: E
authors.initials: E
authors.lastname: Pablik
authors.affiliation: Department of Clinical Pharmacology, Medical University of Vienna, Vienna, Austria.
authors.forename: M
authors.initials: M
authors.lastname: Wolzt
authors.affiliation: Department of General Anaesthesia and Intensive Care Medicine.
authors.forename: W
authors.initials: W
authors.lastname: Plöchl
mesh_terms: D061605:Administration, Intravenous; D000328:Adult; D000732:Androstanols / Q000009:adverse effects / Q000037:antagonists & inhibitors*; D004305:Dose-Response Relationship, Drug; D005240:Feasibility Studies; D005260:Female; D005542:Forearm; D006801:Humans; D058926:Intraoperative Awareness / Q000517:prevention & control; D008297:Male; D008875:Middle Aged; D019148:Neuromuscular Blockade / Q000009:adverse effects / Q000379:methods*; D003473:Neuromuscular Nondepolarizing Agents / Q000009:adverse effects / Q000037:antagonists & inhibitors*; D010243:Paralysis / Q000139:chemically induced; D010865:Pilot Projects; D011183:Postoperative Complications / Q000453:epidemiology; D011446:Prospective Studies; D000077123:Rocuronium; D000077122:Sugammadex; D014111:Tourniquets; D047408:gamma-Cyclodextrins / Q000008:administration & dosage
chemical_list: D000732:Androstanols; D003473:Neuromuscular Nondepolarizing Agents; D047408:gamma-Cyclodextrins; D000077122:Sugammadex; D000077123:Rocuronium
keywords: blood supply; consciousness; gamma-cyclodextrins; intraoperative awareness, prevention & control; sugammadex