Newly Published
Perioperative Medicine  |   August 2018
Comparison of the TOFscan and the TOF-Watch SX during Recovery of Neuromuscular Function
Author Notes
  • From the Department of Anesthesiology, NorthShore University HealthSystem, University of Chicago Pritzker School of Medicine, Evanston, Illinois (G.S.M., J.W.S., S.B.G., T.D.S., M.D., J.B., R.L.N., C.E.M.); and the Department of Anesthesiology, Northwestern University Feinberg School of Medicine, Chicago, Illinois (M.J.A.).
  • Submitted for publication January 3, 2018. Accepted for publication June 19, 2018.
    Submitted for publication January 3, 2018. Accepted for publication June 19, 2018.×
  • Research Support: Supported by the Department of Anesthesiology, NorthShore University HealthSystem (Evanston, Illinois).
    Research Support: Supported by the Department of Anesthesiology, NorthShore University HealthSystem (Evanston, Illinois).×
  • Competing Interests: Dr. Murphy has served on the Advisory Board and as a speaker for Merck (Kenilworth, New Jersey). Dr. Greenberg has served as a speaker for CASMED (Branford, Connecticut). The remaining authors declare no competing interests.
    Competing Interests: Dr. Murphy has served on the Advisory Board and as a speaker for Merck (Kenilworth, New Jersey). Dr. Greenberg has served as a speaker for CASMED (Branford, Connecticut). The remaining authors declare no competing interests.×
  • Correspondence: Address correspondence to Dr. Murphy: Department of Anesthesiology, NorthShore University HealthSystem, 2650 Ridge Avenue, Evanston, Illinois 60201. dgmurphy2@yahoo.com. Information on purchasing reprints may be found at www.anesthesiology.org or on the masthead page at the beginning of this issue. Anesthesiology’s articles are made freely accessible to all readers, for personal use only, 6 months from the cover date of the issue.
Article Information
Perioperative Medicine / Central and Peripheral Nervous Systems / Neuromuscular Diseases and Drugs
Perioperative Medicine   |   August 2018
Comparison of the TOFscan and the TOF-Watch SX during Recovery of Neuromuscular Function
Anesthesiology Newly Published on August 20, 2018. doi:10.1097/ALN.0000000000002400
Anesthesiology Newly Published on August 20, 2018. doi:10.1097/ALN.0000000000002400
Abstract

What We Already Know about This Topic:

  • Monitoring of neuromuscular function recovery using quantitative methods improves patient outcome

  • However, the application of quantitative monitoring is infrequent, in part because current devices are complex and application is time consuming

What This Article Tells Us That Is New:

  • A new generation of quantitative monitoring using three-dimensional acceleromyographic technology, the TOFscan (Drager Technologies, Canada), has been developed that requires minimal setup for intraoperative use

  • TOFscan measures the recovery of neuromuscular function with good agreement to an existing device, the TOF-Watch SX (Organon, Ireland), which requires preload application, calibration, and normalization

Background: Quantitative neuromuscular monitoring is required to ensure neuromuscular function has recovered completely at the time of tracheal extubation. The TOFscan (Drager Technologies, Canada) is a new three-dimensional acceleromyography device that measures movement of the thumb in multiple planes. The aim of this observational investigation was to assess the agreement between nonnormalized and normalized train-of-four values obtained with the TOF-Watch SX (Organon, Ireland) and those obtained with the TOFscan during recovery from neuromuscular blockade.

Methods: Twenty-five patients were administered rocuronium, and spontaneous recovery of neuromuscular blockade was allowed to occur. The TOFscan and TOF-Watch SX devices were applied to opposite arms. A preload was applied to the TOF-Watch SX, and calibration was performed before rocuronium administration. Both devices were activated, and train-of-four values were obtained every 15 s. Modified Bland–Altman analyses were conducted to compare train-of-four ratios measured with the TOFscan to those measured with the TOF-Watch SX (when train-of-four thresholds of 0.2 to 1.0 were achieved).

Results: Bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at nonnormalized train-of-four ratios between 0.2 and 1.0 were 0.021 and −0.100 to 0.141, respectively. When train-of-four measures with the TOF-Watch SX were normalized, bias and 95% limits of agreement between the TOF-Watch SX and the TOFscan at ratios between 0.2 and 1.0 were 0.015 and −0.097 to 0.126, respectively.

Conclusions: Good agreement between the TOF-Watch SX with calibration and preload application and the uncalibrated TOFscan was observed throughout all stages of neuromuscular recovery.