Article Notes

• Hide
  • Pearls
  • Summaries
  • Comments

summary
0
The authors conclude that one-quarter of PACU desaturations below 90%, almost-half of desaturations below 80%, and almost one-third of re-intubations could be attributable to intermediate NMBD.
Grosse-Sundrup M, Henneman JP, Sandberg WS et al. Intermediate acting non-depolarizing neuromuscular blocking agents and risk of postoperative respiratory complications: prospective propensity score matched cohort study. BMJ. 2012 Jan 1;345:e6329.
  Daniel Jolley
comment
1
Interestingly, they found the risk of respiratory complications to be greater in those having shorter procedures (< 2 hours) presumably because of the shorter time between relaxant and extubation.
Grosse-Sundrup M, Henneman JP, Sandberg WS et al. Intermediate acting non-depolarizing neuromuscular blocking agents and risk of postoperative respiratory complications: prospective propensity score matched cohort study. BMJ. 2012 Jan 1;345:e6329.
  Daniel Jolley
comment
0
This is a very significant and large study, and should give us pause to ponder the consequences of invasive airway management and surgery requiring muscle relaxation. It is also important to note that qualitative neuromuscular monitoring (as opposed to quantitative) appears to offer no risk reduction, consistent with other research in this area.
Nonetheless, the retrospective nature of this study means these relationships should not necessarily be viewed as causal. This is not a study of an intervention per se, but the association between certain perioperative characteristics that may be unavoidable (e.g. using muscle relaxants).
An important paper for any concerned anaesthetist or anesthesiologist to read in full.
Grosse-Sundrup M, Henneman JP, Sandberg WS et al. Intermediate acting non-depolarizing neuromuscular blocking agents and risk of postoperative respiratory complications: prospective propensity score matched cohort study. BMJ. 2012 Jan 1;345:e6329.
  Daniel Jolley
summary
1
This very large cohort study demonstrated an association between use of intermediate-duration NMBD and risk of postoperative desaturation and reintubation requiring ICU admission, and a similar association with these outcomes and neostigmine reversal.
Qualitative neuromuscular monitoring did not reduce this risk.
Study population was all patients at Massachusetts General Hospital undergoing general anaesthesia including a muscle relaxant over a 4 year period, and who were extubated at the end of the procedure.
Grosse-Sundrup M, Henneman JP, Sandberg WS et al. Intermediate acting non-depolarizing neuromuscular blocking agents and risk of postoperative respiratory complications: prospective propensity score matched cohort study. BMJ. 2012 Jan 1;345:e6329.
  Daniel Jolley
pearl
1
Post-operative residual paralysis is associated with a greater incidence of desaturation in the post-anaesthesia care unit.
Sauer M, Stahn A, Soltesz S et al. The influence of residual neuromuscular block on the incidence of critical respiratory events. A randomised, prospective, placebo-controlled trial. Eur J Anaesthesiol. 2011 Dec 1; 28 (12): 842-8.
  Daniel Jolley
pearl
1
Partial paralysis with TOFR < 0.9 causes pharyngeal dysfunction and misdirected swallowing, increasing the risk of aspiration.
Sundman E, Witt H, Olsson R et al. The incidence and mechanisms of pharyngeal and upper esophageal dysfunction in partially paralyzed humans: pharyngeal videoradiography and simultaneous manometry after atracurium. Anesthesiology. 2000 Apr 1;92(4):977-84.
  Daniel Jolley
summary
1
Observation of pharyngeal function in 14 awake volunteers demonstrated pharyngeal dysfunction and increased aspiration risk at TOF ratios < 0.90.
“Partial neuromuscular paralysis caused by atracurium is associated with a four- to fivefold increase in the incidence of misdirected swallowing. … The majority of misdirected swallows resulted in penetration of bolus to the larynx.”
(Sundman in a 2000 follow-up study: The incidence and mechanisms of pharyngeal and upper esophageal dysfunction in partially paralyzed humans: pharyngeal videoradiography and simultaneous manometry after atracurium.)
Eriksson LI, Sundman E, Olsson R et al. Functional assessment of the pharynx at rest and during swallowing in partially paralyzed humans: simultaneous videomanometry and mechanomyography of awake human volunteers. Anesthesiology. 1997 Nov 1;87(5):1035-43.
  Daniel Jolley
summary
0
Murphy et al. showed in this randomised, non-blinded trial that patients monitored with quantitative acceleromyography before extubation experienced less PORC, less desaturation below 90% (0% versus 21%) and less airway obstruction (0% versus 11%) during transport to the PACU.
Once in the PACU these patients also experienced less frequent, shorter duration and less severe hypoxic events.
Murphy GS, Szokol JW, Marymont JH et al. Intraoperative acceleromyographic monitoring reduces the risk of residual neuromuscular blockade and adverse respiratory events in the postanesthesia care unit. Anesthesiology. 2008 Sep 1;109(3):389-98.
  Daniel Jolley
pearl
1
Quantitative neuromuscular monitoring reduces the incidence of post-operative residual paralysis, desaturation and airway obstruction.
Murphy GS, Szokol JW, Marymont JH et al. Intraoperative acceleromyographic monitoring reduces the risk of residual neuromuscular blockade and adverse respiratory events in the postanesthesia care unit. Anesthesiology. 2008 Sep 1;109(3):389-98.
  Daniel Jolley
pearl
1
Intrathecal magnesium extends analgesic duration of spinal opioids.
Pascual-Ramírez J, Gil-Trujillo S, Alcantarilla C. Intrathecal magnesium as analgesic adjuvant for spinal anesthesia: a meta-analysis of randomized trials. Minerva Anestesiol. 2013 Jun 1;79(6):667-78.
  Daniel Jolley