Suspicion Of Malignant Hyperthermia Research Articles

Anesthesia for a Patient with Osteogenesis Imperfecta, Achondroplastic Dwarfism and History of Malignant Hyperthermia

A primary goal for anesthesia providers is to maintain patientsafety. This is an even greater concern when taking care of apatient with a complicated medical history. This case report,discusses the care of a 47 year-old female patient who presentedto a tertiary care center for an orthopedic procedure. Hermedical history included osteogenesis imperfecta (OI), achondroplasticdwarfism and suspicion of malignant hyperthermia (MH).There were multiple anesthetic implications to ensure safety forthis patient during the perioperative period. OI concerns includebone fragility and potential for multiple fractures even afterinoffensive trauma. Achondroplastic dwarfism concerns includeabnormalities of the upper airway and difficulty with visualizingthe glottic opening during direct laryngoscopy.1 MalignantHyperthermia is a life threatening disorder, which places thepatient at risk for a hypermetabolic reaction if exposed to selectanesthetic agents.

Association of malignant hyperthermia and exertional heat illness in young athletes: An analysis of awareness among clinical and athletic first responders.

Malignant hyperthermia (MH), a rare inherited condition seen almost exclusively in the perioperative setting, is triggered by volatile anesthetics or an intravenous paralytic drug, succinylcholine. It can, however, occur without any exposure to anesthetic drugs, being associated with heat illness and rhabdomyolysis, thus presenting a little-known risk to young athletes exercising in hot environments. This study aimed to determine the first responder awareness of MH and its association with heat illness in young athletes within athletic and clinical environments. Awareness within the clinical milieu was assessed by an institutional chart review of 3296 charts. The identified heat illness cases were examined for treatment consistent with the management of a suspected episode of MH. Awareness among first responders in an athletic setting was examined by a survey administered to a total of 1,500 coaches and athletic trainers at the high school level along with emergency medical services providers across the United States. No treatment consistent with the suspicion of MH was noted among clinical first responders, suggesting a lack of awareness. Survey administration also revealed a limited amount of knowledge of MH and its potential role in heat illness. The results point to lack of awareness among pre-hospital and hospital-based first responders of the relationship between MH and heat illness in young athletes. An effort to educate these members of the healthcare community can contribute to an expeditious and life-saving intervention. First responders who may interact with a young athlete have low knowledge of MH and its relationship to heat illness. Similar lack of awareness exists among hospital personnel who care for young individuals with heat illness. Educating the first responders about this condition can speed up the time to intervene and save lives.

Profile of malignant hyperthermia susceptibility reports confirmed with muscular contracture test in Brazil

Background and objectivesMalignant hyperthermia is an autosomal dominant hypermetabolic pharmacogenetic syndrome, with a mortality rate of 10%–20%, which is triggered by the use of halogenated inhaled anesthetics or muscle relaxant succinylcholine. The gold standard for suspected susceptibility to malignant hyperthermia is the in vitro muscle contracture test in response to halothane and caffeine. The determination of susceptibility in suspected families allows the planning of safe anesthesia without triggering agents for patients with known susceptibility to malignant hyperthermia by positive in vitro muscle contracture test. Moreover, the patient whose suspicion of malignant hyperthermia was excluded by the in vitro negative muscle contracture test may undergo standard anesthesia. Susceptibility to malignant hyperthermia has a variable manifestation ranging from an asymptomatic subject presenting a crisis of malignant hyperthermia during anesthesia with triggering agents to a patient with atrophy and muscle weakness due to central core myopathy. The aim of this study is to analyze the profile of reports of susceptibility to malignant hyperthermia confirmed with in vitro muscle contracture test. MethodAnalysis of the medical records of patients with personal/family suspicion of malignant hyperthermia investigated with in vitro muscle contracture test, after given written informed consent, between 1997 and 2010. ResultsOf the 50 events that motivated the suspicion of malignant hyperthermia and family investigation (sample aged 27±18 years, 52% men, 76% white), 64% were investigated for an anesthetic malignant hyperthermia crisis, with mortality rate of 25%. The most common signs of a malignant hyperthermia crisis were hyperthermia, tachycardia, and muscle stiffness. Susceptibility to malignant hyperthermia was confirmed in 79.4% of the 92 relatives investigated with the in vitro muscle contracture test. ConclusionThe crises of malignant hyperthermia resembled those described in other countries, but with frequency lower than that estimated in the country.

Perfil dos relatos de suscetibilidade à hipertermia maligna confirmados com teste de contratura muscular no Brasil

Background and objectivesMalignant hyperthermia is an autosomal dominant hypermetabolic pharmacogenetic syndrome, with a mortality rate of 10%‐20%, which is triggered by the use of halogenated inhaled anesthetics or muscle relaxant succinylcholine. The gold standard for suspected susceptibility to malignant hyperthermia is the in vitro muscle contracture test in response to halothane and caffeine. The determination of susceptibility in suspected families allows the planning of safe anesthesia without triggering agents for patients with known susceptibility to malignant hyperthermia by positive in vitro muscle contracture test. Moreover, the patient whose suspicion of malignant hyperthermia was excluded by the in vitro negative muscle contracture test may undergo standard anesthesia. Susceptibility to malignant hyperthermia has a variable manifestation ranging from an asymptomatic subject presenting a crisis of malignant hyperthermia during anesthesia with triggering agents to a patient with atrophy and muscle weakness due to central core myopathy. The aim of this study is to analyze the profile of reports of susceptibility to malignant hyperthermia confirmed with in vitro muscle contracture test. MethodAnalysis of the medical records of patients with personal/family suspicion of malignant hyperthermia investigated with in vitro muscle contracture test, after given written informed consent, between 1997 and 2010. ResultsOf the 50 events that motivated the suspicion of malignant hyperthermia and family investigation (sample aged 27±18 years, 52% men, 76% white), 64% were investigated for an anesthetic malignant hyperthermia crisis, with mortality rate of 25%. The most common signs of a malignant hyperthermia crisis were hyperthermia, tachycardia, and muscle stiffness. Susceptibility to malignant hyperthermia was confirmed in 79.4% of the 92 relatives investigated with the in vitro muscle contracture test. ConclusionThe crises of malignant hyperthermia resembled those described in other countries, but with frequency lower than that estimated in the country.

Comparison of performance on a heat tolerance test of military personnel that have suffered heat illness and subsequently been diagnosed with malignant hyperthermia and controls

The Institute of Naval Medicine runs a Heat Illness Clinic (HIC), seeing about 140 military patients a year who have been referred following an episode of heat illness (HI). Patients undertake assessment of maximal aerobic fitness (VO2max) followed by a heat tolerance test (HTT), in which they walk on a treadmill at 60 % VO2max in a warm environment (34 °C dry bulb, relative humidity 40 % with a WBGT of 27 °C). Initially patients are fully clothed and carry a rucksack (mass 14 kg) to raise the deep body temperature, at 30 min the jacket and rucksack are removed and at 45 min the t-shirt removed. Patients continue to exercise until thermal equilibrium (i.e. a plateau of rectal temperature) is achieved (60 min to 90 min). Rectal temperature (Tre), mean skin temperature (Tmsk), heart rate (HR) and sweat rate (SR) are recorded. Patients in which thermal equilibrium is not achieved are considered to demonstrate abnormal thermoregulation and the HTT. These patients are reviewed at least once a minimum of 8 weeks later, and if they consistently fail the HTT and there is a suspicion of malignant hyperthermia (MH) they are recommended for referral to the Malignant Hyperthermia Unit, Leeds. MH is a genetic condition in which too much calcium is released from the intracellular store into the cytoplasm in response to certain triggering agents, e.g. the anaesthetic halothane. This leads to a rise in cellular metabolism and heat production, particularly within skeletal muscle, and it has been suggested that individuals with underlying MH are more susceptible to HI [1].

Malignant Hyperthermia or Not Malignant Hyperthermia

In an acute event, the diagnosis of malignant hyperthermia (MH) in patients in the ICU can be challenging. Initial presentation may be attributed to a gamut of causes, making the diagnosis complicated. This example is the case of a 46-year-old African American man who was admitted to the Stroke Service and intubated for respiratory distress. To facilitate intubation, he was given etomidate and succinylcholine. Within an hour, a sustained increase in arterial carbon dioxide concentration, rhabdomyolysis, and later on, hyperthermia, developed. He was started on broad-spectrum antibiotics, aggressive fluid hydration, and mechanical ventilation. He had had one previous uneventful anesthesia exposure and he denied having any family member having anesthesia complications. With a very convoluted presentation, a high degree of suspicion for MH warranted appropriate treatment to avoid significant morbidity and/or mortality. Moreover, until the diagnosis is confirmed, education regarding the disease process to patients and their family members is as vital as the treatment itself. The main objective of this case is to present a diagnostic dilemma in a probable MH patient who is in a state of shock in the ICU.

Malignant hyperthermia during general anesthesia for a surgery of idiopathic scoliosis: A case report.

Malignant hyperthermia is a potentially fatal hypermetabolic syndrome characterized by skeletal muscle rigidity and hyperpyrexia. We had an 11-year-old female presented for a surgery for idiopathic scoliosis of the thoracic vertebra. Generalized muscle rigidity and tachycardia were revealed 1 hour 35 minutes after isoflurane administration. Then the body temperature was risen to 43degrees C within 10 minutes and the arterial blood gas analysis showed a severe respiratory and metabolic acidosis. Under the suspicion of malignant hyperthermia, the patient was treated by discontinuing all anesthetic agents, hyperventilation with 100% oxygen, surface cooling with ice pack and the administration of dantrolene sodium. But, the patient died of renal failure and disseminated intravascular coagulation after 50 days postoperatively.

Suspicious Malignant Hyperthermia in Child during General Anesthesia: A case report

We had a 16-month-old male presented for a surgery for degloving injury of left lower extremity. He had no considerable past or family history. High fever and increased end-tidal CO2 with tachycardia was revealed after induction of general anesthesia with thiopental sodium, vecuronium, isoflurane-N2O and O2. Arterial blood gas analysis showed a severe mixed acidosis. Under the suspicion of malignant hyperthermia, all anesthetics were discontinued. Anesthesia was maintained with fentanyl and midazolam. The patient was managed with surface cooling, gastric lavage with cold saline, sodium bicarbonate and diuretics. Dantrolene sodium 50 mg was administered. The patient survived without any sequelae and discharged after 9 days. The etiologic factors, incidence, clinical features, prevention and treatments of malignant hyperthermia are discussed. (Korean J Anesthesiol 1998; 35: 583∼588)

A case of malignant hyperthermia?

An acute episode of a malignant hyperthermia-like syndrome is described which occurred after suxamethonium and isoflurane anaesthesia in a 41-year-old healthy male patient undergoing a minor elective hand operation. Dantrolene therapy rapidly reversed the life-threatening signs. Laboratory results appeared to confirm the suspicion of malignant hyperthermia. However, the in vitro contracture test, which was carried out according to the standards of the European Malignant Hyperthermia Group, was equivocal.