Malignant Hyperthermia is a genetic condition, usually triggered by anaesthetic drugs. It can be managed well if recognised and treated. Find out more
Anyone with suspected MH should undergo testing. A muscle biopsy test is currently the only definitive test for MH. Find out more
The earliest signs of an MH reaction are an increased rate of metabolism and an increase in heart rate, during surgery. Find out more
Read our list of FAQs put together by patients and staff at the MH unit to give further support and information about the condition. Find out more
In most MH cases, the condition is inherited. The most common gene to be associated with MH is the RYR1 gene. Find out more
The MH unit in Leeds is always pleased to hear from patients interested in fundraising or joining our patient liaison group to support others. Find out more
Malignant hyperthermia (MH) is a progressive hyperthermic reaction occurring during general anaesthesia. If not treated well, the condition can prove fatal. Find out more
Please refer any patient with suspected MH to the specialist investigation unit in Leeds. Please ask patients to tell all relatives about their condition. Find out more
MH is a genetic condition which is usually triggered when an individual is exposed to drugs which are commonly used in anaesthetics. Find out more
GPs should encourage any patient with confirmed or suspected MH to sign up to the UK MH Registry; an important research database of all known MH cases. Find out more
A definitive diagnosis of MH requires muscle biopsy testing, which can only take place at the specialist MH Investigation Unit at St James's Hospital, Leeds. Find out more
For further support and information, please call our Patient helpline number Tel: 0113 20 65270 (during office hours) Email: mhunit@leeds.ac.uk Find out more
Malignant hyperthermia (MH) is a condition that only occurs under general anaesthesia. It can be fatal if it is not recognised and managed well. Find out more
Dantrolene is a hydantoin derivative that was originally developed for the treatment of muscle spasticity. It must be stocked on every site where general anaesthesia is administered. Find out more
Exposure to inhalational anaesthetics can trigger a rapidly progressive and potentially fatal increase in metabolism, as can the neuromuscular relaxant, suxamethonium. Find out more
Every hospital pharmacy and anaesthetic departments in every hospital should draw up an action plan to be used in an MH emergency. Find out more
Treatment of includes removal of the triggering drug, cooling of the patient and administration of the antidote, Dantrolene sodium. Find out more
Malignant hyperthermia is a life-threatening reaction to anaesthetic drugs. Between 1: 3,000 and 1: 10,000 people carry the genetic risk of developing malignant hyperthermia during anaesthesia. Find out more
In this situation the initial need is to clarify whether the patient is at risk of MH or not. This can be done by taking as detailed a family history as possible and then contacting the Leeds MH Unit. Find out more
It is important to be aware that patients who are susceptible to MH may not develop the condition every time they have a general anaesthetic. Find out more
MH safe anaesthetics need to be used if a MH susceptible pregnant woman requires anaesthesia or a pregnant woman whose partner is MH susceptible requires anaesthesia. Find out more
These patients are often very well informed about their condition and its implications but may also be particularly anxious about receiving an anaesthetic. Find out more
A specific obstetric care plan needs to be devised for the MH susceptible parturient or the parturient with a MH susceptible partner. Find out more
It is vital that operating theatre staff are able to understand the signs of MH and their role in treatment of a crisis. Find out more
Those at risk can receive anaesthetics safely as long as the inhalational anaesthetics and suxamethonium are avoided. Find out more
This page outlines what should be available for management of an MH crisis and should be fetched or ordered immediately. After stabilisation of the patient it is vital that the data from the monitor are stored and downloaded so that a retrospective record of events can be made. Find out more
Any patient who is known to have MH, or is suspected of having MH, should be scheduled to be the first case on an elective list. The main principle of management of these patients is that they are not exposed to sufficient concentrations of triggering agents to risk the development of an MH reaction Find out more
MH susceptibility predisposes to a potentially fatal reaction to the most commonly used anaesthetic drugs. Find out more
Ryanodine receptor 1 (skeletal); RYR1 and Calcium channel, voltage-dependent, L type, alpha 1S subunit; CACNA1S Find out more
The number of new cases of malignant hyperthermia presenting with a clinical reaction has averaged approximately 25 per year over the last 10 years. Find out more
The diagnostic guidelines of the European Malignant Hyperthermia Group (EMHG) provide a framework that balances the definitive but invasive and more expensive in vitro contracture test with DNA testing which lacks sensitivity. Find out more
By definition MH can only occur under general anaesthesia. This is to distinguish it from other forms of heat illness, where an assessment of cerebral function is needed to make the diagnosis. Find out more
Malignant hyperthermia is a life-threatening reaction to anaesthetic drugs. The term “malignant” hyperthermia arises from the progressive nature of the condition. Find out more
It is vital that all anaesthetists understand that a history of apparently uneventful general anaesthesia does not exclude underlying malignant hyperthermia susceptibility. Find out more
Once an increased risk of MH susceptibility is confirmed the management of anaesthesia is founded on the need to avoid exposure of the patient to triggering agents. Find out more
The cardinal features of malignant hyperthermia result from an uncontrollable increase in intracellular calcium ions within the skeletal muscles. Find out more
An MH treatment algorithm should be prominently displayed or available in every location where general anaesthesia is administered. Find out more
By definition, malignant hyperthermia is characterised by a rapid, progressive, potentially fatal increase in body temperature that occurs in susceptible individuals during general anaesthesia. Find out more
The great majority of patients susceptible to malignant hyperthermia have no neuromuscular symptoms or signs. Find out more
The preferred first line of investigation for a patient presenting to the neurology clinic with features associated with MH susceptibility is DNA analysis. Find out more
When significance of a variant with respect to MH susceptibility is unknown, it is appropriate for the patient to be offered definitive testing for MH susceptibility using muscle biopsy and in vitro contracture tests. Find out more
A 2009 issue of Anesthesia & Analgesia contained some interesting reviews on the relationship between MH and various muscle disorders. Find out more