Performance of acceleromyography with a short and light TOF-tube compared with mechanomyography

Abstract

Compared with mechanomyography, acceleromyography performed with the aid of an SL TOF-Tube offered acceptable precision and equivalent performance during neuromuscular block recovery.

Conceptual and technical insights into the basis of neuromuscular monitoring

“…In addition to the need for pre‐use calibration, AMG monitors cannot be used clinically when unencumbered movement of the thumb is not assured, such as surgical procedures in which the arms are placed at the patient's side under surgical drapes. A work‐around may be to protect the monitored arm and thumb inside a TOF‐tube, but the limits of agreement between mechanomyography (see below) and AMG were in the range of ‐19% to +24% when the TOF ratio was 0.9 . Furthermore, the use of the recommended Hand Adapter that maintains a preload to improve precision also increases the average control TOF ratios from 1.07 (no pre‐load) to 1.13 (with a significant range between TOF = 1.01–1.23).…”

Monitoring recovery from rocuronium-induced neuromuscular block using acceleromyography at the trapezius versus the adductor pollicis muscle: an observational trial

“…The repeatability of these measurements was assessed using the withinindividual measurements that were analyzed by means of a one-way analysis of variance. The individual repeatability coefficients (calculated as 1.96 H2SD) 5,11,12 for all patients were compared between both measurement sites with a paired Student's t test. At each recording site, onset of neuromuscular block, time to 25% T1 recovery, and time to 90% TOF recovery were compared with a paired Student's t test.…”

“…14 While measurement of neuromuscular blockade at the adductor pollicis muscle is considered standard practice, 5,6 this might be difficult in some cases because of limited access to the extremities. 12 In clinical practice, a 0.9 TOF ratio recorded at the adductor pollicis muscle is considered to indicate adequate recovery from neuromuscular block. [1][2][3][4] Nevertheless, in this study, a TOF ratio of 0.9 recorded at the trapezius muscle corresponded to a TOF ratio of only about 0.8 at the adductor pollicis muscle.…”

“…Nevertheless, the repeatability coefficients we recorded at the trapezius muscle are comparable with the data published in other studies concerned with acceleromyographic responses at the adductor pollicis muscle. 12,16 It is well known that the time course of neuromuscular block can vary depending on the site of measurement of evoked responses. The onset is considerably faster at the larynx, 17 diaphragm, 1 and masseter muscle 18,19 than at the adductor pollicis muscle.…”

Pharmacokinetics and pharmacodynamics of rocuronium in young adult and elderly patients undergoing elective surgery

“…Several situations can affect the quality of measurements using AMG, and thus, several anaesthesiologists are reluctant to adopt AMG instead of MMG. The interferences with the thumb's movement include (1) movements of the surgical team when in contact with the arm; (2) the restrictive role of the adhesive tapes on the patient's hand; and (3) possible contact of the thumb with other fingers, the palm or the patient's thigh when the arm is positioned alongside the body …”