The implementation of quantitative electromyographic neuromuscular monitoring in an academic anesthesia department

Anesth Analg. 2014 Aug;119(2):323-331. doi: 10.1213/ANE.0000000000000261.


Background: Although experts agree on the importance of quantitative neuromuscular blockade monitoring, particularly for managing reversal, such monitoring is not in widespread use. We describe the processes and results of our departmental experience with the introduction of such quantitative monitoring.

Methods: In mid-2010, the senior authors became concerned about the management of nondepolarizing neuromuscular blockers (NMB) by providers within the department, based on personal observations and on a review of a departmental quality assurance/adverse event database. This review indicated the occurrence of 2 to 4 reintubations/year in the postanesthesia care unit (PACU) that were deemed to be probably or possibly related to inadequate reversal. In response, quantitative blockade equipment (Datex-Omeda ElectroSensor™ EMG system) was installed in all our main operating rooms in January 2011. This introduction was accompanied by an extensive educational effort. Adoption of the system was slow; by mid-2011, the quantitative system was being used in <50% of cases involving nondepolarizing relaxants and adverse NMB-related events continued to occur. Therefore, starting in August 2011 and extending over the next 2 years, we performed a series of 5 separate sampling surveys in the PACU in which train-of-four (TOF) ratios were recorded in 409 tracheally extubated adult patients who had received nondepolarizing NMB (almost exclusively rocuronium) as well as in 73 patients who had not received any nondepolarizing NMB. After each survey, the results were presented to the entire department, along with discussions of individual cases, reviews of the recent literature regarding quantitative monitoring and further education regarding the use of the quantitative system.

Results: In the initial (August 2011) PACU survey of 96 patients receiving nondepolarizing NMBs, 31% had a TOF ratio of ≤0.9, 17% had a ratio of ≤0.8, and 4 patients (4%) had ratios of ≤0.5. A record review showed that the quantitative monitoring system had been used to monitor reversal in only 51% of these patients, and 23% of patients had no evidence of any monitoring, including qualitative TOF assessment. By December of 2012 (after 2 interim PACU monitoring surveys), a fourth survey showed 15% of 101 monitored patients had a TOF ratio ≤0.9, and only 5% had ratios ≤0.8. (P < 0.05 vs August 2011). Clear documentation of reversal using the quantitative system was present in 83% of cases (P < 0.05 vs August 2011). A final survey in July 2013 showed nearly identical values to those from December 2012. The lowest TOF ratio observed in any patient not receiving a nondepolarizing NMB was 0.92. There were no changes in the patterns of either rocuronium or neostigmine use over the duration of the project (through December 2012), and there have been no cases of NMB-related reintubations in the PACU during the last 2 years.

Discussion: Implementation of universal electromyographic-based quantitative neuromuscular blockade monitoring required a sustained process of education along with repeated PACU surveys and feedback to providers. Nevertheless, this effort resulted in a significant reduction in the incidence of incompletely reversed patients in the PACU.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Academic Medical Centers / organization & administration*
  • Academic Medical Centers / standards
  • Anesthesia Department, Hospital / organization & administration*
  • Anesthesia Department, Hospital / standards
  • Anesthesia Recovery Period
  • Drug Utilization Review
  • Education, Medical, Continuing
  • Electromyography* / standards
  • Feedback, Psychological
  • Humans
  • Intraoperative Neurophysiological Monitoring / methods*
  • Intraoperative Neurophysiological Monitoring / standards
  • Iowa
  • Medical Audit
  • Neuromuscular Blockade / adverse effects
  • Neuromuscular Blockade / methods*
  • Neuromuscular Monitoring* / standards
  • Neuromuscular Nondepolarizing Agents / adverse effects
  • Neuromuscular Nondepolarizing Agents / therapeutic use*
  • Organizational Objectives
  • Postoperative Complications / prevention & control
  • Practice Patterns, Physicians'*
  • Predictive Value of Tests
  • Program Development
  • Program Evaluation
  • Quality Improvement
  • Quality Indicators, Health Care
  • Time Factors


  • Neuromuscular Nondepolarizing Agents