DP16: POTENTIAL MALIGNANT HYPERTHERMIA IN A PRETERM INFANT UNDERGOING NEUROSURGICAL SURGERY
Arden Woods, DO; Erick Rodriguez, MD; Eric Harris, MD; Alain Harb, MD
University of Miami/Jackson Memorial Hospital
Introduction/Background: Malignant Hyperthermia (MH) is a life-threatening pharmacogenetic disorder that can be triggered by exposure to volatile anesthetics and succinylcholine. Early recognition and management are crucial, especially in pediatric and neonatal populations where presentations may be atypical. Here we describe the case of a pre-term infant manifesting the signs of malignant hyperthermia after exposure to sevoflurane, prompting treatment with dantrolene.
Methods: We present the case of a 32-week gestational age female infant, born at 23 weeks, who had a history of respiratory distress syndrome, treated urosepsis, grade 4 intraventricular hemorrhage, and hydrocephalus. The patient was scheduled for the placement of a right frontal Rickham reservoir. Anesthesia was induced using fentanyl, propofol, and rocuronium and maintained with sevoflurane. Although the surgery began with a stable course, intraoperative concerns emerged when the end-tidal CO2 (ETCO2) rose from 34 to the high 40s/low 50s (despite increased respiratory rate, tidal volumes, flows, and checks of the circuit and absorbent for faults), alongside tachycardia (heart rate increased from 145 to 175 bpm in the abscence of surgical stimulation) and a rising temperature (from 35.9°C to 37.6°C). At this time, concern was raised for potential malignant hyperthermia and the MH hotline was consulted. A venous blood gas and creatinine kinase were drawn at the same time that showed a significant respiratory acidosis and a CK of 328. Given the unusually young presentation in a patient with low skeletal muscle mass and decreased ability to mount a large MH response, IV dantrolene 2.5 mg/kg was administered despite down trending end tidal CO2, tachycardia and temperature as the procedure ended. The patient was then transferred to the NICU intubated.
Results: After administration of dantrolene and transfer back to the NICU, patient showed clinical improvement, normalization of her acidosis, and declining creatine kinase levels from 328 to 55. Genetic testing and a halothane contracture test were recommended. It is important to note however that there are no normal standard normal levels for creatinine kinase in this population. Patient was successfully extubated to CPAP on postoperative day three and was eventually discharged months later after management of her other comorbidities.
Discussion/Conclusion: This case emphasizes the importance of vigilance and early recognition of possible signs/symptoms of MH, particularly in populations like premature neonates where classical signs may be absent. In such populations where low muscle mass and a lack of standard normal laboratory values for creatinine kinase cloud the clinical picture, empiric treatment of malignant hyperthermia could prevent further morbidity and mortality. There is limited existing literature pertaining to this population, with the earliest verified cases in 2 patients – 16 day old and 6 week old patients. One of these cases resolved without administration of dantrolene and the other necessitated resuscitation and extended ICU care. Given the scarcity and heterogenicity of presentation, continuous vigilance, capnography monitoring, and readiness to administer dantrolene are essential for ensuring safe anesthetic management.