This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Girard, T. Articles by Urwyler, A. Search for Related Content PubMed Articles by Girard, T. Articles by Urwyler, A.

---

LETTER TO THE EDITOR

Not Every Hypermetabolic State Is Due to Malignant Hyperthermia!

Department of Anesthesia; University Hospital Basel; CH 4031 Basel; Switzerland; thierry.girard{at}unibas.ch

To the Editor:

We have concerns about the diagnosis of malignant hyperthermia (MH) in a recent case report by Lichtman and Oribabor (1). As the authors stated "several items in this patient’s postoperative course were atypical ...." One hour postoperatively the patient developed a hypermetabolic state with combined respiratory and metabolic acidosis. This state was successfully treated with dantrolene. The fact that dantrolene was effective is not surprising. Muscle rigidity from any cause places considerable metabolic demand on the body, which is effectively attenuated by blocking sarcoplasmic calcium release by dantrolene. Indeed, dantrolene is effective in other hypermetabolic diseases, such as malignant neuroleptic syndrome (2) and is an effective therapeutic strategy to reduce muscle protein breakdown and muscle lactate formation (3).

Despite the potentially positive family history and muscle rigidity, there were no other clinical signs of MH. There are many reasons for postoperative hypermetabolic states, e.g., sepsis, hypoperfusion, and propofol infusion syndrome (4–6). It would have been useful had the authors discussed alternatives and not focused on only one possible diagnosis.

MH is defined as a pharmacogenetic disease, where triggering agents (volatile anesthetic agents and depolarizing neuromuscular blocking agents) initiate a hypermetabolic reaction in genetically susceptible patients. This definition separates MH from other hypermetabolic states. We do not question the choice of dantrolene for this patient, although we are not aware of the evidence to initiate an oral dantrolene therapy. We similarly are unaware of evidence to support the conclusion to consider off-pump CABG rather than traditional hypothermic CPB in MH susceptible individuals.

Lastly, although we respect the patient’s decision to refuse testing for MH, we are disappointed that further testing could not be done. Molecular genetic investigations are now available in North America (7) and alternative minimal invasive methods have been recently presented (8). It is particularly odd that patient without symptomatic cardiac disease would agree to coronary bypass grafting in order to improve his preoperative condition for the planned shoulder surgery, but refuse testing for MH, and why the currently proposed diagnostic approach for MH testing has not been applied to this patient and his family (7).

REFERENCES

1. Lichtman AD, Oribabor C. Malignant hyperthermia following systemic rewarming after hypothermic cardiopulmonary bypass. Anesth Analg 2006;102:372–5.[Abstract/Free Full Text]
2. Lappa A, Podesta M, Capelli O, et al. Successful treatment of a complicated case of neuroleptic malignant syndrome. Intensive Care Med 2002;28:976–7.[Web of Science][Medline]
3. Hotchkiss RS, Karl IE. Dantrolene ameliorates the metabolic hallmarks of sepsis in rats and improves survival in a mouse model of endotoxemia. Proc Natl Acad Sci USA 1994;91:3039–43.[Abstract/Free Full Text]
4. Leverve XM. Inter-organ substrate exchanges in the critically ill. Curr Opin Clin Nutr Metab Care 2001;4:137–42.[Web of Science][Medline]
5. Eriksen J, Povey HM. A case of suspected non-neurosurgical adult fatal propofol infusion syndrome. Acta Anaesthesiol Scand 2006;50:117–9.[Web of Science][Medline]
6. Liolios A, Guerit JM, Scholtes JL, Raftopoulos C, Hantson P. Propofol infusion syndrome associated with short-term large-dose infusion during surgical anesthesia in an adult. Anesth Analg 2005;100:1804–6.[Abstract/Free Full Text]
7. Litman RS, Rosenberg H. Malignant hyperthermia: update on susceptibility testing. JAMA 2005;293:2918–24.[Abstract/Free Full Text]
8. Bina S, Cowan G, Karaian J et al. Effects of caffeine, halothane, and 4-chloro-m-cresol on skeletal muscle lactate and pyruvate in malignant hyperthermia-susceptible and normal swine as assessed by microdialysis. Anesthesiology 2006;104:90–100.[Web of Science][Medline]

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Web of Science (1) Citing Articles via Google Scholar Google Scholar Articles by Girard, T. Articles by Urwyler, A. Search for Related Content PubMed Articles by Girard, T. Articles by Urwyler, A.