This topic was selected because an evidence synthesis beats a textbook on it: the trials disagree, or the guidance has moved recently.
THE EVIDENCE
What each source contributes, and how strong it is
Study design first — a cohort and a randomised trial do not carry the same weight.
Design
Year
Journal
What it found
Meta-analysis
2025
British journal of anaesthesia
Where quantitative monitoring and sugammadex are readily available, residual block
Randomised trial
2008
Anesthesiology
Randomising to acceleromyography rather than qualitative train-of-four cut residual
Cohort
2015
Anesthesia and analgesia
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a
Review
2018
Anesthesia and analgesia
Absence of fade on a peripheral nerve stimulator does not exclude residual block —
Guideline
2018
Anesthesia and analgesia
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative
Randomised trial
2011
Anesthesiology
Acceleromyography reduced residual block from 50% to 14.5% and left patients with
6 resolved citations behind this deck; every point above traces to one of them.
WHERE THE GUIDANCE SITS
What the guidelines and pooled evidence say
2 findings, each on the slide that follows.
British journal of anaesthesia 2025
Where quantitative monitoring and sugammadex are readily available, residual block
Where quantitative monitoring and sugammadex are readily available, residual block in recovery fell to 2.2%, against published incidences ranging…
Anesthesia and analgesia 2018
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative device: documenting a train-of-four ratio of at least 0.90 is the…
WHERE THE GUIDANCE SITS
Where quantitative monitoring and sugammadex are readily available, residual block
Meta-analysis · British journal of anaesthesia
Where quantitative monitoring and sugammadex are readily available, residual block in recovery fell to 2.2%, against published incidences ranging from 3.5% to 53.3% since 2000.
Residual Neuromuscular Block in the Postanaesthesia Care Unit: A Single-Centre Prospective Observational Study and Systematic Review, British journal of anaesthesia 2025 · PMID 39443187
THE NUMBERS
Where quantitative monitoring is routine, the problem nearly disappears
500 patients, Dutch centre with monitors and sugammadex available.
2.2% in a centre where quantitative monitoring and sugammadex were routinely available, against published incidences up to 53%. Cross-study comparison, not a controlled one.
Residual Neuromuscular Block in the Postanaesthesia Care Unit: A Single-Centre Prospective Observational Study and Systematic Review, British journal of anaesthesia 2025 · PMID 39443187
WHERE THE GUIDANCE SITS
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative
Guideline · Anesthesia and analgesia
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative device: documenting a train-of-four ratio of at least 0.90 is the only way to confirm satisfactory recovery, and the 5-second head lift should be abandoned.
Consensus Statement on Perioperative Use of Neuromuscular Monitoring, Anesthesia and analgesia 2018 · PMID 29200077
WHAT THE TRIALS FOUND
Where randomised evidence moved the question
2 findings, each on the slide that follows.
Anesthesiology 2008
Randomising to acceleromyography rather than qualitative train-of-four cut residual
Randomising to acceleromyography rather than qualitative train-of-four cut residual blockade in recovery from 30% to 4.5%
Anesthesiology 2011
Acceleromyography reduced residual block from 50% to 14.5% and left patients with
Acceleromyography reduced residual block from 50% to 14.5% and left patients with fewer symptoms of weakness, even though visible signs of weakness…
WHAT THE TRIALS FOUND
Randomising to acceleromyography rather than qualitative train-of-four cut residual
Randomised trial · Anesthesiology
Randomising to acceleromyography rather than qualitative train-of-four cut residual blockade in recovery from 30% to 4.5%, and no acceleromyography patient desaturated below 90% or obstructed during transport.
Intraoperative Acceleromyographic Monitoring Reduces the Risk of Residual Neuromuscular Blockade and Adverse Respiratory Events in the Postanesthesia Care Unit, Anesthesiology 2008 · PMID 18719436
THE NUMBERS
Acceleromyography cut residual block sevenfold
185 patients randomised to quantitative or qualitative monitoring.
No acceleromyography patient desaturated or obstructed during transport. None.
Intraoperative Acceleromyographic Monitoring Reduces the Risk of Residual Neuromuscular Blockade and Adverse Respiratory Events in the Postanesthesia Care Unit, Anesthesiology 2008 · PMID 18719436
WHAT THE TRIALS FOUND
Acceleromyography reduced residual block from 50% to 14.5% and left patients with
Randomised trial · Anesthesiology
Acceleromyography reduced residual block from 50% to 14.5% and left patients with fewer symptoms of weakness, even though visible signs of weakness were rare in both groups.
Intraoperative Acceleromyography Monitoring Reduces Symptoms of Muscle Weakness and Improves Quality of Recovery in the Early Postoperative Period, Anesthesiology 2011 · PMID 21946094
IN PRACTICE
What the cohorts and reviews add
2 findings, each on the slide that follows.
Anesthesia and analgesia 2015
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a train-of-four ratio under 0.9 at extubation — clinical judgement plus a…
Anesthesia and analgesia 2018
Absence of fade on a peripheral nerve stimulator does not exclude residual block —
Absence of fade on a peripheral nerve stimulator does not exclude residual block — train-of-four ratios as low as 0.4 to 0.6 can be present when no…
IN PRACTICE
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a
Cohort · Anesthesia and analgesia
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a train-of-four ratio under 0.9 at extubation — clinical judgement plus a nerve stimulator does not detect residual block.
The RECITE Study: A Canadian Prospective, Multicenter Study of the Incidence and Severity of Residual Neuromuscular Blockade, Anesthesia and analgesia 2015 · PMID 25902322
THE NUMBERS
Neostigmine plus a nerve stimulator is not enough
RECITE, 302 patients, blinded acceleromyography.
Two-thirds still had residual block at extubation despite routine reversal and qualitative monitoring.
The RECITE Study: A Canadian Prospective, Multicenter Study of the Incidence and Severity of Residual Neuromuscular Blockade, Anesthesia and analgesia 2015 · PMID 25902322
IN PRACTICE
Absence of fade on a peripheral nerve stimulator does not exclude residual block —
Review · Anesthesia and analgesia
Absence of fade on a peripheral nerve stimulator does not exclude residual block — train-of-four ratios as low as 0.4 to 0.6 can be present when no fade is visible.
Neuromuscular Monitoring in the Perioperative Period, Anesthesia and analgesia 2018 · PMID 28795964
IN THE ROOM
What this changes about the next case
Colour is the strength of the evidence behind each step, not the urgency.
1
1
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative device: documenting a train-of-four ratio of at least 0.90 is the only way to confirm satisfactory recovery, and the 5-second head lift should be abandoned.
2
2
Where quantitative monitoring and sugammadex are readily available, residual block in recovery fell to 2.2%, against published incidences ranging from 3.5% to 53.3% since 2000.
3
3
Randomising to acceleromyography rather than qualitative train-of-four cut residual blockade in recovery from 30% to 4.5%, and no acceleromyography patient desaturated below 90% or obstructed during transport.
4
4
Acceleromyography reduced residual block from 50% to 14.5% and left patients with fewer symptoms of weakness, even though visible signs of weakness were rare in both groups.
5
5
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a train-of-four ratio under 0.9 at extubation — clinical judgement plus a nerve stimulator does not detect residual block.
The oral-boards stem on the next slide puts these into one scenario.
KEY TAKEAWAYS
What to carry into the next case
Where quantitative monitoring and sugammadex are readily available, residual block
British journal of anaesthesia 2025
Randomising to acceleromyography rather than qualitative train-of-four cut residual
Anesthesiology 2008
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a
Anesthesia and analgesia 2015
Absence of fade on a peripheral nerve stimulator does not exclude residual block —
Anesthesia and analgesia 2018
Where quantitative monitoring and sugammadex are readily available, residual block
Questions I'll ask you in the room
How does your plan change if the patient is not optimised?
What is the physiology behind what we just did?
Talk me through the trade-off you made there.
What would make you abandon this plan and do something else?
Oral boards stem
A CA-1 has judged reversal adequate on a peripheral nerve stimulator by eye and wants to extubate. The quantitative monitor is in the drawer and would take a minute to set up.
Board questions
1. State the core recommendations of the 2018 consensus statement on perioperative use of neuromuscular monitoring: when monitoring is indicated, where on the body and with what type of device, the numeric endpoint that confirms satisfactory recovery, and which traditional bedside test the statement says to abandon.
Show answer
Whenever a neuromuscular blocker is given, monitor at the hand with a quantitative device; documenting a train-of-four ratio of at least 0.90 is the only way to confirm satisfactory recovery, and the 5-second head lift should be abandoned.
The consensus is unambiguous: any neuromuscular blocker means a quantitative device at the hand and a documented train-of-four ratio of at least 0.90, and the 5-second head lift is no longer acceptable as proof.
Consensus Statement on Perioperative Use of Neuromuscular Monitoring, Anesthesia and analgesia 2018 · PMID 29200077
2. A resident sees no fade in the train-of-four response on a peripheral nerve stimulator and concludes that residual neuromuscular block has been excluded. State what range of train-of-four ratios can be present when no fade is visible, and say whether the resident's conclusion holds.
Show answer
The conclusion does not hold: absence of fade on a peripheral nerve stimulator does not exclude residual block, because train-of-four ratios as low as 0.4 to 0.6 can be present when no fade is visible.
Your eye saturates well before the neuromuscular junction recovers, so a ratio anywhere from 0.4 to 0.6 can hide behind a train-of-four that looks fade-free.
Neuromuscular Monitoring in the Perioperative Period, Anesthesia and analgesia 2018 · PMID 28795964
3. In the RECITE study, patients were managed with qualitative neuromuscular monitoring and neostigmine reversal. State the proportion who still had a train-of-four ratio under 0.9 at extubation, and what the study establishes about clinical judgement combined with a nerve stimulator.
Show answer
Despite qualitative monitoring and neostigmine, 63.5% of patients still had a train-of-four ratio under 0.9 at extubation, which shows that clinical judgement plus a nerve stimulator does not detect residual block.
Nearly two thirds of RECITE patients reached extubation with a train-of-four ratio under 0.9, which is why judgement plus a qualitative stimulator cannot be your detection strategy.
The RECITE Study: A Canadian Prospective, Multicenter Study of the Incidence and Severity of Residual Neuromuscular Blockade, Anesthesia and analgesia 2015 · PMID 25902322
4. A single-centre prospective observational study, published alongside a systematic review, found residual neuromuscular block in the recovery unit in 2.2% of patients in a setting where quantitative monitoring and sugammadex were readily available, against published incidences ranging from 3.5% to 53.3% since 2000. State what this comparison does and does not establish.
Show answer
It establishes that in a setting where quantitative monitoring and sugammadex were readily available the observed incidence of residual block in recovery was 2.2%, at or below the bottom of the 3.5% to 53.3% range published since 2000. It does not establish that those two practices caused the low rate: the comparator is a wide range of incidences from other studies over 25 years rather than a concurrent randomized control group.
This is an observed incidence in one setting benchmarked against a very wide historical range, so treat it as consistent with the practice, not as proof that the monitor and sugammadex produced the number.
Residual Neuromuscular Block in the Postanaesthesia Care Unit: A Single-Centre Prospective Observational Study and Systematic Review, British journal of anaesthesia 2025 · PMID 39443187
The bottom lineWhere quantitative monitoring and sugammadex are readily available, residual block
Sources
[1] Residual Neuromuscular Block in the Postanaesthesia Care Unit: A Single-Centre Prospective Observational Study and Systematic Review, British journal of anaesthesia 2025 · PMID 39443187 open
[2] Intraoperative Acceleromyographic Monitoring Reduces the Risk of Residual Neuromuscular Blockade and Adverse Respiratory Events in the Postanesthesia Care Unit, Anesthesiology 2008 · PMID 18719436 open
[3] The RECITE Study: A Canadian Prospective, Multicenter Study of the Incidence and Severity of Residual Neuromuscular Blockade, Anesthesia and analgesia 2015 · PMID 25902322 open
[4] Neuromuscular Monitoring in the Perioperative Period, Anesthesia and analgesia 2018 · PMID 28795964 open
[5] Consensus Statement on Perioperative Use of Neuromuscular Monitoring, Anesthesia and analgesia 2018 · PMID 29200077 open
[6] Intraoperative Acceleromyography Monitoring Reduces Symptoms of Muscle Weakness and Improves Quality of Recovery in the Early Postoperative Period, Anesthesiology 2011 · PMID 21946094 open