Malignant Hyperthermia

Malignant Hyperthermia is a rare and potentially life threatening genetically inherited condition that can be triggered by drugs commonly used in anaesthesia. If it is not recognised and treated in its early stages, MH can be fatal.

In 1962, Denborough and colleagues reported that 10 members of a Melbourne family had previously died during or shortly after having general anaesthesia. Over time it was identified that the cause was due to an inherited pharmacogenetic disorder - Malignant Hyperthermia (MH).

Malignant Hyperthermia is a rare and potentially life threatening genetically inherited condition that can be triggered by drugs commonly used in anaesthesia.  The most common triggering agents are volatile anaesthetic agents, such as sevoflurane, desflurane, isoflurane, and depolarizing muscle relaxants such as succinylcholine. In MH susceptible individuals other less common causes  include heat stress, and extreme exercise.

MH has an estimated incidence of <0.02%(2), occurring between 1:5,000-1:10,000 procedures involving general anaesthesia(3)

In the 1970s, mortality was greater than 80%; however with current management strategies, mortality is less than 5%(3).  

The disorder has been reported worldwide, affecting all racial groups. The highest incidence of MH in the world is found in the Manawatu region of New Zealand, with up to 1:200 people identified with the condition(4).

There is no cure for the autosomal dominant genetic predisposition to MH. It is hereditary being passed from parent to child. There is a 50% occurrence that a person with MH will pass the gene onto each child they have.  

An In Vitro Contracture test (IVCT) test is currently the only definitive test for MH.  The group Malignant Hyperthermia Australia & New Zealand have identified 4 locations for MH testing across Australia & New Zealand.  

If it is not recognised and treated in its early stages, MH can be fatal. General anaesthesia can be achieved avoiding triggering agents if patients are known or suspected to have MH. Clinicians involved in general anaesthesia must be aware of the signs and symptoms of Malignant hyperthermia and in order to quickly identify and effectively manage patients who develop this condition.  

If patients show signs and symptoms of MH, a rapid response is essential, all triggering agents must be discontinued, and attention focused on clinical deterioration including correcting hyperthermia, acidosis, hypercarbia, muscle rigidity, rhabdomyolysis, and organ dysfunction. Intravenous administration of Dantrolene (Dantrolene™, Ryanodex™) is the primary treatment, and the only known antidote in conjunction with other supportive measures.  

The Malignant Hyperthermia Australia and New Zealand, MH Resource Kit (published August, 2018 and endorsed by ANZCA Council in September 2018) is a comprehensive kit that can be downloaded and used by facilities using MH triggering agents on patients undergoing general anaesthesia www.malignanthyperthermia.org.au

If you are interested in gaining more knowledge on this topic and others relating to Anaesthetics & PACU nursing,  you can enrol in our live virtual classroom via the link below.

https://medcast.com.au/education/anaesthesia-pacu-nursing

For other courses relating to Anaesthetic & PACU nursing, and a full list of events and courses visit https://medcast.com.au/critical-care

Authors: Danielle Grace and Ken Hambrecht for Critical Care Education Services

References:

The New England Journal of Medicine. Date accessed: 14/10/2020.

Science Direct Date accessed 14/10/2020.

[2] Rosenberg H, Sambuughin N, Riazi S, Dirksen R. Malignant Hyperthermia Susceptibility. In: Pagon RA, Adam MP, Ardinger HH, Bird TD, Dolan CR, Fong CT, et al., editors. Gene Reviews. Seattle (WA)1993.

(3) Rosenberg H, Davis M, James D, Pollock N, Stowell K (April 2007). "Malignant hyperthermia". Orphanet Journal of Rare Diseases. 2: 21. Wikipedia - DOI, DOI, Wikipedia - PMC, NCBI, Wikipedia - PMID, Pubmed

(4) Rosenberg, Henry; Pollock, Neil; Schiemann, Anja; Bulger, Terasa; Stowell, Kathryn (4 August 2015). "Malignant hyperthermia: a review". Orphanet Journal of Rare Diseases. 10 (1): 93. Wikipedia - DOI, DOI, Wikipedia - PMC, NCBI, Wikipedia - PMID, Pubmed

Halsall PJ, Hopkins PM; Hopkins (2003). "Malignant hyperthermia". Continuing Education in Anaesthesia, Critical Care and Pain. 3 (1): 5–9. Wikipedia - DOI, DOI, Archived from the original on 2006-10-03.Malignangt Hyperthermia Australia & New Zealand 

Clinical Anesthesiology 3rd Edition.  International Edition.  2002.  p869-873.  Morgan, Mikhail, Murray, with Larson. Published by Lange Medical Books/McGraw-Hill.

Rosenberg H, Davis M, James D, Pollock N, Stowell K (April 2007). "Malignant hyperthermia". Orphanet Journal of Rare Diseases. 2: 21. Wikipedia - DOI, DOI, Wikipedia - PMC, NCBI, Wikipedia - PMID, Pubmed

Australian and New Zealand College of Anaesthetics.  Malignant Hyperthermia Malignant Hyperthermia  Site accessed 25/9/2020 

{{commentCount}} comment(s). You must be logged in and AHPRA verified to view and comment. Log In here.

Danielle Grace

The latest healthcare news from medcast

A tree change is in the wind
A tree change is in the wind

Change seems to be the theme of 2020. In our region, as with many in Australia, it started with bushfires, before a jump to the left into ‘COVID Capers’.

Writing your COVID worries away - (with Andrew Gan and Dr Jet)
Writing your COVID worries away - (with Andrew Gan and Dr Jet)

COVID and all its attendant inconveniences (I guess some would say “tortures”) has forced many of us to revise our personal wellbeing plans and dig out some old strategies that we haven’t used for a while. It’s also made some of us realise that ma...

Malignant Hyperthermia
Malignant Hyperthermia

Malignant Hyperthermia is a rare and potentially life threatening genetically inherited condition that can be triggered by drugs commonly used in anaesthesia. If it is not recognised and treated in its early stages, MH can be fatal.

Restless Leg Syndrome - Podcast
Restless Leg Syndrome - Podcast

Restless leg syndrome is a common presentation in General Practice characterised by uncomfortable sensations in the legs. These sensations are associated with an irresistible urge to move the legs to relieve the symptoms.

Telehealth Fatigue
Telehealth Fatigue

My patients are loving telehealth. They love it so much that most of them are saying they don’t want to come back to face to face consultations. You probably need to bear in mind that my patients are long-term therapy patients that I know very well.

Paediatric Advanced Life Support Standards
Paediatric Advanced Life Support Standards

In order to achieve these standards, it is essential that medical and nursing staff who work with paediatric patients receive specialised education to manage a paediatric cardiopulmonary arrest.

Would learning something new wash your Acedia away?
Would learning something new wash your Acedia away?

Is Acadia running your life right now? Are you, like the solitary monks who used that term in the middle ages, suffering from the combination of boredom, frustration, agitation and lethargy that comes with physical isolation?

COVID conspiracies – should we ignore them?
COVID conspiracies – should we ignore them?

Like me, you probably spend a lot of time talking to people about how they feel about the COVID 19 pandemic, but do you talk to them about their thoughts and beliefs about it?

Medication Spotlight: Paracetamol
Medication Spotlight: Paracetamol

A frequently used medication in community and hospital settings is paracetamol (named acetaminophen in some countries). It has less adverse effects than other analgesics, as it has no effect on platelet functioning and allergies are very rare.

Helping prevent suicide among Australia's Indigenous Youth
Helping prevent suicide among Australia's Indigenous Youth

Suicide in Australia amongst Aboriginal and Torres Strait Islander peoples occur at twice the rate of the general population. Young Aboriginal and Torres Strait Islander people are at even greater risk, those aged 5 to 17 years, suicide is the le...

COVID-19 – A Clinical Update Webinar
COVID-19 – A Clinical Update Webinar

SARS-CoV-2 pandemic is having an unprecedented impact on global health and economics. Australian GPs are on the frontline and they are forced to make decisions in a medical landscape where the parameters for testing are changing daily and many pa...

Why should we be laughing?
Why should we be laughing?

Right now, most of us are a bit upset in one way or another. Some of us are very upset. Stress, frustration, grief, anxiety, sadness, isolation, loneliness, worry about the present, worry about the future – all these things are rising to the surfa...

Aging Well – a personal perspective
Aging Well – a personal perspective

At 65 and a half (yes, it’s come to that. I’m actually counting the months again!) I find myself reluctantly looking down the barrel of a shotgun labelled “old age”.  It’s OK, don’t panic – I’m not unwell. It’s just that my body hurts and people k...

The CHIME GP study
The CHIME GP study

Clinical and Healthcare Improvement through My Health Record Usage and Education in General Practice

Muuuum, I’m bored!!!!
Muuuum, I’m bored!!!!

Has anyone heard that or a variation of it recently? I’ll bet you have! Many years ago, before I had kids of my own, I used to hear my brother-in-law saying to his bored and whining kids “Come on then, I’ll give you a job. I’ve got plenty for y...

What’s your COVID number? A simple way to keep everyone safe and comfortable
What’s your COVID number? A simple way to keep everyone safe and comfortable

A friend mentioned a really great way for managing this which I have been using and sharing with others. As people are going to have different comfort levels when it comes to spending time together, she told me about sharing her COVID social comfo...

Being Well in Difficult Times - Talah
Being Well in Difficult Times - Talah

It’s always helpful to hear how other people cope.  Over the next few weeks we are dedicating the Being Well blog to a series called Being Well in Difficult Times.  In this blog post we speak to Talah - a a Gumbaynggirr/Yaegl young person who shar...

We’re listening at last to Aboriginal and Torres Strait Islander Voices in Mental Health
We’re listening at last to Aboriginal and Torres Strait Islander Voices in Mental Health

Whilst significant progress has been made in incorporating these voices generally, there is a call for diversity in these Lived Experience voices, namely Aboriginal and Torres Strait Islander Lived Experience.

Being Well in Difficult Times- Zoe
Being Well in Difficult Times- Zoe

Zoe is a registered nurse working in theatres. She has elderly parents and a young son. How is she staying so positive in the face of CoVID-19?

Eating Disorders in Adults: Assessment & Treatment Options
Eating Disorders in Adults: Assessment & Treatment Options

Eating disorders, broadly defined by disturbances in eating behaviour and distress centred on food, eating, and body image, affect nearly one million Australians. This blog covers the assessment and treatment options for various conditions.

Join Medcast. It's free and you'll get instant access to essential healthcare news, research and more.

Already a member? Log In