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Development of an algorithm using clinical tests to avoid post-operative residual neuromuscular block.
Christoph Unterbuchner1,2, Manfred Blobner3, Friedrich Pühringer4
1Klinik für Anaesthesiologie, Klinikum rechts der Isar, Technische Universität München, Munich, Ismaninger Str. 22, 81675, Munich, Germany. Christoph.unterbuchner@ukr.de.
BMC Anesthesiology
|August 6, 2017
Summary
A new algorithm using four muscle function tests can reliably detect postoperative residual curarization (PORC) in awake patients. This method offers an alternative when quantitative neuromuscular monitoring is unavailable, ensuring patient safety.
Area of Science:
- Anesthesiology and critical care medicine
- Clinical pharmacology and therapeutics
- Patient monitoring and safety
Background:
- Quantitative neuromuscular monitoring is the gold standard for detecting postoperative residual curarization (PORC).
- Many clinicians rely on less sensitive qualitative monitoring or unreliable clinical tests.
- This study aimed to develop a muscle function test algorithm to identify PORC.
Purpose of the Study:
- To develop and validate an algorithm of muscle function tests for identifying postoperative residual curarization (PORC).
- To compare the algorithm's performance against quantitative electromyography (EMG) and uncalibrated acceleromyography.
- To provide a reliable alternative for PORC detection when advanced monitoring is unavailable.
Main Methods:
- A multicentre, prospective, double-blinded study involving 165 patients undergoing neuromuscular monitoring.
- Eight clinical muscle function tests were performed post-extubation and correlated with calibrated EMG train-of-four (TOF) ratio.
- A classification and regression tree (CART) algorithm was developed and validated in a separate cohort of 100 patients.
Main Results:
- A four-test algorithm (arm lift, head lift, swallowing/eye opening) demonstrated high sensitivity (100%) in predicting EMG TOF values.
- Uncalibrated acceleromyography showed higher specificity than the algorithm for detecting TOF ratios <0.7 and <0.9.
- Tactile TOF fading assessment exhibited the lowest sensitivity and specificity.
Conclusions:
- An algorithm of four clinical muscle function tests can effectively detect residual neuromuscular blockade in awake patients.
- This algorithm serves as a viable alternative to uncalibrated acceleromyography when quantitative monitoring is not accessible.
- The developed algorithm demonstrates comparable discriminative power to uncalibrated acceleromyography for specific TOF value ranges.
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