Emergence
Neuromuscular monitoring & reversal
Measure, don’t guess. Residual paralysis is common and invisible to clinical signs.
Train-of-four: count vs. ratio
Four stimuli at 2 Hz over the ulnar nerve, watching the adductor pollicis (thumb). The count (0–4) estimates depth; the ratio (T4/T1) needs a quantitative monitor — you can’t see fade reliably by eye above ≈ 0.4.
Depth of block (ASA 2023)
| Depth | Measurement | Typical reversal (rocuronium/vecuronium) |
|---|---|---|
| Intense | Post-tetanic count (PTC) 0 | Wait (or 16 mg/kg sugammadex for immediate reversal after 1.2 mg/kg rocuronium) |
| Deep | PTC ≥ 1, TOF count 0 | Sugammadex 4 mg/kg |
| Moderate | TOF count 1–3 | Sugammadex 2 mg/kg |
| Shallow | TOF count 4, ratio < 0.4 | Sugammadex 2 mg/kg |
| Minimal | TOF ratio 0.4 to < 0.9 | Neostigmine (+ glycopyrrolate) is reasonable, or sugammadex |
| Adequate recovery | TOF ratio ≥ 0.9 | — |
Figure: Acceleromyography monitoring with preload hand adapter — Paul Anthony Stewart, CC BY-SA 4.0, via Wikimedia Commons. Resized and converted to WebP.
Pimp questions
Pimp question 1
Why are four visible twitches an incomplete handoff?
Answer
Fade is hard to see above a ratio of ≈ 0.4; four twitches can coexist with significant residual weakness. Report the measured ratio and site.
Pimp question 2
Why monitor the adductor pollicis rather than the orbicularis oculi?
Answer
Facial muscles recover earlier and overestimate recovery of the airway and respiratory muscles.
Pimp question 3
Sugammadex dose at TOF count 2?
Answer
2 mg/kg (actual body weight).