Malignant hyperthermia in the oral and maxillofacial surgery patient: an update

Malignant hyperthermia in maxillofacial surgery: Literature review supported by case presentation

OBJECTIVE

Malignant hyperthermia (MH) is characterized by a state of hypermetabolism after exposure to halogenated inhalational anesthetics or succinylcholine. The aims of this study were to carry out an updated review on the subject and report an illustrative case of MH in urgent maxillofacial surgery.

MATERIAL AND METHODS

A search of the PubMed/MEDLINE database using the keyword "malignant hyperthermia" was performed including articles published over the last 11 years in English, Spanish or Portuguese. Exclusion criteria were similar presentations but not associated with MH and cases not related to the use of anesthetic drugs as a trigger of the condition.

CASE REPORT

A 45-year-old man (75 kg, ASA status IE) with a negative family history for neuromuscular diseases, victim of a car accident with a facial fracture, underwent surgery under balanced general anesthesia and developed signs of MH 4 h after anesthesia induction. In our patient, the causative agent was sevoflurane and the diagnosis of MH was confirmed, subsequently, by muscle biopsy.

RESULTS/DISCUSSION

Overall, 44 cases of MH were found. According to the recent literature, MH shows a male predilection (3:1) and the mean age of patients is 32.2 ± 22.2 years. The most frequently cited causative agents were sevoflurane (30.5%), isoflurane (22.2%), and sevoflurane + succinylcholine (13.8%). The most common clinical indicators included hypercarbia (88.8%), hyperthermia (86.1%), and tachycardia (63.8%). Dantrolene was administered in 24 cases. The outcome was favorable in 31 cases (86.1%). The in vitro muscle contracture test (IVCT) was performed in only 15 patients and all of them tested positive. In our patient, the causative agent was sevoflurane and the diagnosis of MH was confirmed by muscle biopsy.

CONCLUSION

The mortality from MH is still high and an early clinical diagnosis and specific treatment with dantrolene are necessary for a favorable outcome. A complete understanding will allow better management of patients with MH. At present, the best management is to identify susceptible patients and to avoid triggering agents, combined with vigilant monitoring.

Fever after maxillofacial surgery: a critical review

PURPOSE

The aim of this paper is to review the pathophysiology of thermoregulation mechanism, various causes of fever after maxillofacial surgery and the different treatment protocols advised in the literature.

DISCUSSION

Fever is one of the most common complaints after major surgery and is also considered to be an important clinical sign which indicates developing pathology that may go unnoticed by the clinician during post operative period. Several factors are responsible for fever after the maxillofacial surgery, inflammation and infection being the commonest. However, other rare causes such as drug allergy, dehydration, malignancy and endocrinological disorders, etc. should be ruled out prior to any definite diagnosis and initiate the treatment. Proper history and clinical examination is an essential tool to predict the causative factors for fever. Common cooling methods like tepid sponging are usually effective alone or in conjunction with analgesics to reduce the temperature.

CONCLUSION

Fever is a common postoperative complaint and should not be underestimated as it may indicate a more serious underlying pathology. A specific guideline towards the management of such patients is necessary in every hospital setting to ensure optimal care towards the patients during post operative period.