Which muscle group is used to monitor extubation readiness when assessing recovery from neuromuscular blockade?

Which muscle group is used to monitor extubation readiness when assessing recovery from neuromuscular blockade?

• A. Orbicularis oculi
• B. Diaphragm
• C. Adductor pollicis (ulnar nerve)
• D. Masseter

Answer: (C)

Monitoring recovery from neuromuscular blockade relies on quantitative tests that reflect when skeletal muscles have regained enough strength for safe extubation. The adductor pollicis, assessed via stimulation of the ulnar nerve, is the preferred muscle group for this purpose. Its response to train-of-four stimulation correlates well with the overall return of neuromuscular function, including the ability to protect the airway. When the train-of-four ratio reaches about 0.9, most muscles have recovered sufficiently to allow extubation, and airway reflexes are more likely to be intact. Other muscles don’t offer the same reliability. The muscles around the eyes can recover earlier and may give a falsely reassuring impression of full recovery. The diaphragm is the critical breathing muscle, but it’s not easily monitored with peripheral nerve stimulation, and recovery there doesn’t always match safe extubation readiness. The masseter can behave differently from other muscles under blockade, potentially delaying or confusing judgments about readiness.

Monitoring recovery from neuromuscular blockade relies on quantitative tests that reflect when skeletal muscles have regained enough strength for safe extubation. The adductor pollicis, assessed via stimulation of the ulnar nerve, is the preferred muscle group for this purpose. Its response to train-of-four stimulation correlates well with the overall return of neuromuscular function, including the ability to protect the airway. When the train-of-four ratio reaches about 0.9, most muscles have recovered sufficiently to allow extubation, and airway reflexes are more likely to be intact.

Other muscles don’t offer the same reliability. The muscles around the eyes can recover earlier and may give a falsely reassuring impression of full recovery. The diaphragm is the critical breathing muscle, but it’s not easily monitored with peripheral nerve stimulation, and recovery there doesn’t always match safe extubation readiness. The masseter can behave differently from other muscles under blockade, potentially delaying or confusing judgments about readiness.