the metablog

Posts written by Daniel Jolley.
Daniel Jolley

About the author

Daniel Jolley is an anesthesiologist, founder and CEO of metajournal, providing personalized medical research recommendations to fellow doctors.

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Sugammadex and rocuronium anaphylaxis

I have been intrigued since the first case reports appeared describing the use of sugammadex in rocuronium anaphylaxis. It sounds beautiful and elegant. A drug that magically mops up the offending molecule, removing it from circulation; quickly reversing the cardiovascular collapse as rapidly as it reverses muscle relaxation.

The little we know

  1. There have been case reports from 5 countries showing dramatic improvement of rocuronium-confirmed anaphylaxis after administration of sugammadex.
  2. One case study showed a dose-dependent effect of sugammadex on modifying anaphylaxis.
  3. There are not yet any published cases of rocuronium anaphylaxis where sugammadex was administered without clinical improvement (though beware).
  4. Sugammadex although incompletely encapsulating rocuronium, does prevent the rocuronium epitope from binding IgE.
  5. Cutaneous and in vitro models of hypersensitivity have shown no or limited ability of sugammadex to modify type 1 hypersensitivty after triggering.
  6. Our understanding of the pathophysiology of anaphylaxis is over-simplified and incomplete.

Unfortunately the truth is not quite as clear. Case reports showing impressive recovery of rocuronium anaphylaxis minutes after giving sugammadex are tempered by in vitro and in vivoimmunological studies suggesting an inability of sugammadex to modify a type 1 hypersensitivity reaction. The reality is likely somewhere in between, highlighting our limited understanding of anaphylaxis and our tendency to rush to over-simplified models of disease processes.

The story so far...

Jones and Turkstra first raised the possibility of using sugammadex to treat rocuronium anaphylaxis in 2010.1 One year later Nolan McDonnell and team published the first case report of a remarkable use of sugammadex to manage rocuronium anaphylaxis.2 McDonnell described a 33 year old having an elective diagnostic laparoscopy suffering anaphylaxis to rocuronium. After 19 min of conventional resuscitation, involving CPR, 3500 mL of intravenous fluids and 4 mg of epinephrine/adrenaline - 500 mg of sugammadex was given with remarkable effect:

"A dose of 500 mg (6.5 mg kg21) was given while chest compressions were in progress. The last dose of epinephrine had been given 4 min previously. Approximately 45 s after administration and while chest compressions were in progress, the patient suddenly opened her eyes and reached for her tracheal tube.

Read more...


  1. Jones PM, Turkstra TP. Mitigation of rocuronium-induced anaphylaxis by sugammadex: the great unknown. Anaesthesia. 2010 Jan;65(1):89-90; author reply 90. 

  2. McDonnell NJ, Pavy TJ, Green LK, Platt PR. Sugammadex in the management of rocuronium-induced anaphylaxis. Br J Anaesth. 2011 Feb;106(2):199-201. 

Cartoons reduce anxiety during anesthesia induction in children

Two studies caught my eye in Anesthesia & Analgesia. Teams from both Canada and South Korea independently investigated the anxiolytic value of using cartoons during paediatric induction.

The concept is not new, though this evidence is. The teams looked at different admission and induction types and in two distinctly different cultures, but showed very similar and significant benefits of using cartoons during pediatric induction.

Both papers highlighted the cost of perioperative anxiety in children. Anyone with even a passing pediatric anesthetic practice will agree with the reported 50% incidence of perioperative anxiety. Intense anxiety is associated with negative behavioural adaptations, some of which persist for months or longer. Severe childhood anxiety at anesthetic induction is almost as distressing for parents and anesthetist alike as it is for the poor child.

Read more...

Combatting decision fatigue in anaesthesia and critical care

Dynamic decision making' describes the practice of anaesthesia more than any other single characteristic - and anaesthesia is characterised by dynamic decision making more than any other medical speciality. The typical surgical case requires the anaesthetist or anesthesiologist to make hundreds of decisions, modified to suit the evolving environment of the case. Each decision itself modifies the patient context, creating a multiverse of decision and outcome possibilities.

"No plan survives contact with the [surgeon and patient] – Helmuth von Moltke

These decisions add up. Big and small, decision after decision over the day leads to a measurable fall in the quality of our decisions by the final case. Psychologists describe this as 'ego depletion', colloquially called 'decision fatigue'.1

Though not yet widely appreciated in medicine (though it is gaining traction on the medical front-line2), decision fatigue has been identified in many decision-focused professions. Decision fatigue has been identified in judges ruling on cases, with parole decisions made later in the day being of 'lesser quality' and having lower rates of parole than those at the start of the day (10% vs 70% for the first case of the day heard).3

"We find that the percentage of favorable rulings drops gradually from ~65% to nearly zero within each decision session and returns abruptly to ~65% after a break."

Read more...


  1. Tierney J. "Do You Suffer From Decision Fatigue?". New York Times Magazine. August 21 2011. 

  2. Oto B. When thinking is hard: managing decision fatigue. EMS World. 2012 May;41(5):46-50. 

  3. Danzigera S, Levav J, Avnaim-Pessoa L, "Extraneous factors in judicial decisions", Proceedings of the National Academy of Sciences. Feb 25 2011. 

Sugammadex, suxamethonium and the rapid sequence induction

Does sugammadex mean the end of suxamethonium for rapid sequence induction?

The answer: No, not by a long shot. Let me explain...

Suxamethonium (succinylcholine) is a depolarising muscle relaxant and often the first choice for muscle paralysis when a rapid sequence induction (RSI)1 is needed. In addition to working quickly suxamethonium has a very rapid offset. For both anaesthetist and patient these are very desirable characteristics, although they come at a price. The price is suxamethonium's long list of side effects, ranging from minor to life threatening.2 Were it not for it's life-saving fast-kinetics, suxamethonium's use in modern anaesthesia would no longer be justifiable.

This article is part two in a three part series beginning with 'If sugammadex is the answer, what is the question?'.

Enter rocuronium

When rocuronium was first introduced in the 1990s it was met with excitement.3 Rocuronium's claim to fame was a very fast onset of action. Because it was less potent than other non-depolarising muscle relaxants of its generation (atracurium & vecuronium) a larger dose was required to achieve the same level of muscle paralysis. This dose created a large concentration gradient between plasma and the neuromuscular junction resulting in a faster onset of action. By giving a very large dose of rocuronium the anaesthetist could produce acceptable intubating conditions within 60 seconds, creation the first reliable modified rapid sequence induction.

Unfortunately the result of using such a large dose of rocuronium is a prolonged blockade. Even at lower doses (0.6 mg/kg 2x ED95) rocuronium produces a block that lasts at least five times longer than suxamethonium. At the 1.2 mg/kg (4x ED95) modified-RSI-dose of rocuronium the block duration stretches out even longer, reaching the duration of pancuronium. In the event of being unable to intubate, or worse unable to ventilate, prolonged blockade is disastrous. At this point rocuronium only provided half a solution for the replacement of suxamethonium.

Read more...


  1. The rapid sequence induction, as the name suggests, involves very fast induction of general anaesthesia with rapid intubation of the trachea in order to protect the airway quickly, often in emergency situations. 

  2. Most significantly, anaphylaxis, hyperkalaemia and malignant hyperthermia, and also including suxamethonium apnoea and various cardiac arrythmias. Not to mention the 'minor' side effect of feeling run over by a truck after recovering from a suxamethonium paralysis. Suxamethonium adverse effects - wikipedia 

  3. Hunter JM. Rocuronium: the newest aminosteroid neuromuscular blocking drug. Br J Anaesth. 1996 Apr;76(4):481-3. 

Articles and metajournal Notes

A great way to capture and share knowledge gleaned from the evidence is with...

You may have noticed that suggested articles arriving in your emailed metajournal or appearing in online article lists have a pearl or summary above the abstract. My aim is to make keeping up to date and understanding the current literature even more time efficient.

You can add your own notes to any article or abstract you read — both to help you capture the most actionable 'take-away' message, and also to share your wisdom with others. Simple scroll down below the article abstract to find a list of notes and a text-box for you to add your own.

Notes can be either pearls, summaries or comments, depending on the type of information you want to share.

Two examples of articles with notes to get you started:

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