A Noninvasive Investigation of Muscle Energetics Supports Similarities Between Exertional Heat Stroke and Malignant Hyperthermia (original) (raw)
Related papers
Is there a link between malignant hyperthermia and exertional heat illness? * COMMENTARY
British Journal of Sports Medicine, 2007
Exertional heat illness (EHI) and malignant hyperthermia (MH) are two potentially lethal conditions. It has been suggested that a subset of MH susceptible persons may be predisposed to EHI. We examine the current understanding of these disorders and explore evidence of a relationship. Screening for the muscle type I ryanodine receptor gene should help clarify the relationship between MH and EHI.
Journal of Science and Medicine in Sport
Objectives. The study was undertaken to examine the thermal and biochemical responses to a heat tolerance test (HTT) of malignant hyperthermia (MH) susceptible individuals, and compare these with the responses of volunteers who have suffered heat illness (HI) and control volunteers. Methods. Three groups of male volunteers (n=6 in each group) were recruited to the study: MHS-civilian volunteers previously diagnosed as MH susceptible; EHI-military volunteers with a history of exertional HI; CON-military volunteers with no history of HI or MH. For the HTT, volunteers walked on a treadmill at 60 % maximal oxygen uptake in an environmental chamber (mean [SD] temperature 35.5 [0.4] °C, relative humidity 43 [1] %). Measurements were made to assess thermoregulation and biochemistry. Results. There were no differences in deep body temperature, oxygen uptake or serum lactate concentrations between the three groups, although one MHS volunteer and two EHI volunteers failed to thermoregulate. Serum myoglobin concentration and the increase in serum myoglobin was higher in MHS than EHI and CON Post HHT (P<0.05). Conclusion. MH susceptibility does not always predispose an individual to heat intolerance during an acute HTT, but does appear to increase muscle breakdown. The inclusion of serum myoglobin measurements to a HTT may help to distinguish patients that are potentially MHS or have an underlying muscle myopathy, and who otherwise demonstrate thermal tolerance.
Malignant hyperthermia. A case report
Journal of the American Podiatric Medical Association, 1976
Malignant hyperthermia (MH) is a very rare inherited disorder. The incidence of MH is 1: 100 000 although the prevalence of susceptibility to MH is estimated at 1:2000 to 1:3000. MH has a mortality rate of 9.5%. MH is an autosomal dominant disorder and three genes account for the genetic basis of 70% of the patients-RYR1, CACNA1S and STAC3. MH is characterized by an increased body metabolism with hyperthermia, increased carbon dioxide production, skeletal muscle rigidity along with rhabdomyolysis, hyperkalaemia and acidosis with hyperlactacidaemia. These occur when a MH-susceptible individual is exposed to some known triggers such potent volatile anaesthetics and succinylcholine. We present a case report of MH in 22-year-old male ASA II, without any personal or familial MH susceptibility known, admitted to elective dental extraction who suffered a MH crisis. The patient was treated for MH and demonstrated a significant clinical improvement with the administration of dantrolene. RESUMO A hipertermia maligna (HM) é uma doença genética muito rara. A sua incidência é de 1:100000, embora a prevalência de suscetibilidade à doença seja estimada em 1:2000 a 1:3000. A HM tem uma taxa de mortalidade de 9,5%. Trata-se de um distúrbio autossómico dominante e 3 genes são responsáveis por 70% dos casos-RYR1, CACNA1S e STAC3. Caracteriza-se por um aumento do metabolismo corporal com hipertermia, produção aumentada de dióxido de carbono, rigidez músculo-esquelética, rabdomiólise, hipercalémia e acidose com hiperlactacidémia. A crise de HM acontece quando indivíduos suscetíveis são expostos a determinados triggers como os anestésicos voláteis e a succinilcolina. Apresentamos um caso clínico de um doente de 22 anos, sexo masculino, ASA II, sem história pessoal ou familiar de suscetibilidade à HM conhecida, admitido para cirurgia eletiva de extração dentária, que apresentou uma crise de HM. O doente apresentou melhoria clinica significativa após a administração de dantroleno.
Exertional Heat Illness, Exertional Rhabdomyolysis, and Malignant Hyperthermia
Current Sports Medicine Reports, 2008
heat illness, exertional rhabdomyolysis, and malignant hyperthermia: Is there a link? Curr. Sports Med. Rep. Vol. 7, No. 2, pp. 74Y80, 2008. This short review discusses possible links between exertional heat illness (EHI), malignant hyperthermia (MH), and exertional rhabdomyolysis (ER). Evidence on clinical, genetic, and functional aspects, though limited, is compared through individual case reports and a small number of clinical studies. Typically, MH occurs during anesthesia and surgery, EHI during strenuous exercise in hot and humid environments, and ER unrelated to heat and humidity after strenuous exercise. Genetic analysis of the RYR1 gene has identified various mutations, especially in MH, but also in some cases of EHI and in number of ER cases as well. Pathophysiologically, loss of intracellular calcium control appears to be a common feature. Recommendations for treatment and recovery include cooling and administration of dantrolene for MH, cooling and aggressive fluid administration for EHI, and physical rest and aggressive intravenous fluid administration for ER.
Round Table on Malignant Hyperthermia in Physically Active Populations: Meeting Proceedings
Journal of Athletic Training, 2017
Context: Recent case reports on malignant hyperthermia (MH)-like syndrome in physically active populations indicate potential associations among MH, exertional heat stroke (EHS), and exertional rhabdomyolysis (ER). However, an expert consensus for clinicians working with these populations is lacking. Objective: To provide current expert consensus on the (1) definition of MH; (2) history, etiology, and pathophysiology of MH; (3) epidemiology of MH; (4) association of MH with EHS and ER; (5) identification of an MH-like syndrome; (6) recommendations for acute management of an MH-like syndrome; (7) special considerations for physically active populations; and (8) future directions for research. Setting: An interassociation task force was formed by experts in athletic training, exercise science, anesthesiology, and emergency medicine. The “Round Table on Malignant Hyperthermia in Physically Active Populations” was convened at the University of Connecticut, Storrs, September 17–18, 20...