RGB Medical NMT (TOF) Monitor Detailed Product Guide: Origin, Technology and Scientific Studies
RGB Medical NMT (TOF) Monitor Detailed Product Guide: Origin, Technology and Scientific Studies
This page is intended for healthcare professionals. Read the instructions for use before using the device.
Manufacturer and origin
- Manufacturer: RGB Medical Devices, S.A. (Madrid, Spain)
- Founded: In 1988 as a university spin-off.
- Expertise: Develops bedside monitors and vital signs monitoring systems for operating rooms and intensive care units. According to the company, its products are used in more than 2,000 hospitals worldwide. Some of its products are also supplied as OEM to international monitor manufacturers.
- Regulatory status: The TOF-Cuff monitor received US FDA 510(k) clearance on 9 May 2019 (K181894). Intended use per the clearance: monitoring of neuromuscular transmission and non-invasive blood pressure, for use exclusively in healthcare institutions by trained healthcare professionals.
- Türkiye: Prizma Med Sağlık Hizmetleri is the exclusive Türkiye distributor for RGB Medical.
Technology: Compressomyography (CMG)
NMTCuff® (TOF-Cuff) is a cuff similar to a standard blood pressure cuff, with built-in stimulation electrodes. The cuff is placed on the arm; the electrodes stimulate the nerves, and contraction of the arm muscles is measured as a pressure change inside the cuff. The same cuff also measures non-invasive blood pressure.
- Dual function: TOF (train-of-four) measurement and NIBP in a single cuff
- No electrode placement needed: The electrodes are integrated into the cuff.
- Pneumatic measurement: The measurement connection between the device and the patient is pneumatic, not electrical.
- Easy access: Can be used when the arms are under drapes or tucked at the patient's side, i.e., when access to the thumb is difficult.
What do the guidelines say?
The 2023 guideline of the American Society of Anesthesiologists (ASA) recommends quantitative monitoring rather than clinical observation in patients receiving neuromuscular blockade, and confirmation of a TOF ratio of 0.9 or higher before extubation. The guideline recommends the adductor pollicis muscle of the thumb as the monitoring site. NMTCuff®, by contrast, measures from the arm muscles. Its values are therefore not identical to those of devices measuring from the thumb (see the studies below).
Scientific studies
1. Veiga Ruiz et al., 2017 (Spain)
Monitoring intraoperative neuromuscular blockade and blood pressure with one device (TOF-Cuff): a comparative study with mechanomyography and invasive blood pressure. Rev Esp Anestesiol Reanim 2017;64(10):560-567.
- Method: In 32 patients undergoing elective surgery, TOF-Cuff was compared with the reference method, mechanomyography (MMG); in 17 patients, non-invasive blood pressure was compared with invasive arterial pressure.
- Finding: TOF-Cuff was found to be valid and safe for monitoring neuromuscular block. However, it is not interchangeable with MMG: a TOF ratio above 0.9 on TOF-Cuff corresponded to a value above 0.7 on MMG (specificity 91%, positive predictive value 84%). Recovery was measured earlier with TOF-Cuff than with MMG.
- Blood pressure: The mean difference from invasive measurement was 1.6 ± 7 mmHg for systolic and −3.4 ± 6.3 mmHg for diastolic pressure, within European accuracy requirements. No adverse events were observed.
2. Sfeir Machado et al., 2020 (Switzerland)
Assessment of spontaneous neuromuscular recovery: a comparison of the TOF-Cuff® with the TOF Watch SX®. Acta Anaesthesiol Scand 2020;64(2):173-179.
- Method: In elective surgical patients receiving rocuronium, TOF-Cuff was compared with the acceleromyographic TOF Watch SX on the opposite thumb during spontaneous recovery (27 patients analyzed).
- Finding: TOF-Cuff indicated recovery on average 16 minutes earlier. When TOF-Cuff indicated full recovery, the mean TOF ratio measured with TOF Watch SX was 0.59. The authors' conclusion: TOF-Cuff overestimates spontaneous recovery compared with TOF Watch SX.
3. Radkowski et al., 2024 (Poland)
Comparison of measurements obtained with TOF-Cuff placed on the arm and the TOF-Scan on the adductor pollicis muscle during general anaesthesia using mivacurium. Scientific Reports 2024;14:27180.
- Method: TOF-Cuff (arm) and TOF-Scan (thumb) were compared simultaneously in 25 patients.
- Finding: A strong correlation between the two devices was found at the onset of block. During recovery, a consistent bias between the devices was detected. The authors found overall agreement to be good but noted that both devices could give false results in some patients.
What to know for clinical practice
- NMTCuff® values are not identical to those of acceleromyographic or electromyographic devices measuring from the thumb (adductor pollicis); during recovery, it may show a higher TOF ratio.
- The extubation decision should be made based on the monitor value together with clinical assessment and your institution's protocol.
- NMTCuff® may be a practical option when access to the thumb is difficult and in settings where quantitative monitoring is not performed at all. Its ease of setup may make it easier for quantitative monitoring to become routine practice.
Demo and training requests
For clinical evaluation, a demo device and user training: Phone +90 342 360 64 50 · WhatsApp +90 533 349 61 62 · info@prizmamed.com.tr
RGB Medical NMT (TOF) Monitor product page
Sources: Veiga Ruiz G et al. Rev Esp Anestesiol Reanim 2017;64(10):560-7. · Sfeir Machado E et al. Acta Anaesthesiol Scand 2020;64(2):173-179. · Radkowski P et al. Sci Rep 2024;14:27180. · Thilen SR et al. 2023 American Society of Anesthesiologists Practice Guidelines for Monitoring and Antagonism of Neuromuscular Blockade. Anesthesiology 2023;138:13-41. · FDA 510(k) K181894. · HiPEAC institution profile: RGB Medical Devices. Origin information is based on the manufacturer's public statements.