Acute MH in a child in a dental office
A 5-year old 16-kg male child is brought to a freestanding dental office for dental restorations. He is otherwise healthy and during preoperative evaluation family denied anesthesia related problems. The child had received an uneventful general anesthetic when he was 2 years old for pressure equalization tubes placement.
Induction Agents: The child was NPO and was induced in the dental-office in the presence of the mother. Mask induction was with nitrous oxide in oxygen and sevoflurane. A peripheral i.v. was placed successfully and the child was nasally intubated without muscle relaxants; instead the anesthesia was deepened with sevoflurane to allow this to occur smoothly.
Maintenance: was with sevoflurane plus nitrous oxide in oxygen. The child was allowed to breathe spontaneously and given +3 CPAP. The vital signs were stable (H.R. 88 bpm; BP 95/65 mm Hg; SPO2 100%; Axillary temperature 36.3º C; RR 21/min; ETCO2 was 42 mmHg). The child received maintenance fluids and after approximately 2.5 hours the anesthesiologist noted an increase in respiratory rate (increased from 21 to 35/min), ETCO2 also increased steadily to 60 to 80 to 106 mmHg within 4 mins. This was accompanied by an increase in axillary temperature from 36.3 to 36.9ºC. All this was accompanied by an increase in HR to 140 bpm while the SPO2 remained at 100%.
Anesthesiologist response: The anesthesiologist stopped the sevoflurane, nitrous oxide and provided hyperventilation manually with 100% oxygen. A diagnosis of MH was made and the surgical team was immediately notified. A 911-ambulance call was made for MH crisis while 2 ampoules (40 mg) of dantrolene were quickly prepared and administered and an additional larger i.v. placed to administer a fluid flush (normal saline 10 ml/kg);
Surgical team response: The procedure was terminated and assistance provided in establishing the larger i.v. and removed blankets that covered the child to promote surface cooling (ambient air). Alert a local emergency room about the situation and arrange for transfer
Ambulance arrival: The ambulance arrived with 2 individuals (driver and a paramedic). The paramedic indicated that he had no training to take care of a child with MH before. The anesthesiologist administered rocuronium with propofol and agreed to accompany the child to the local E.R. A battery-operated infusion pump was available in the ambulance and was used provide propofol infusion.
Arrival in the E.R.: There was limited expertise available in the local E.R. The anesthesiologist continued to lead the care. A blood gas was obtained: pH 7.10 PaCO2 93 PaO2 210 base excess -4 despite manual hyperventilation, lack of skeletal muscle rigidity and the lungs being compliant. A foley catheter was placed, the urine was clear. Another dose of dantrolene (1 mg/kg) was administered and the child was transported to a pediatric hospital (20 miles distance). Electrolytes, glucose, CK were within normal limits.
Arrival and care at Children’s Hospital: Significant expertise was available at this hospital. He was taken directly to the PICU where further care included administration of dantrolene per MHAUS guidelines. Blood gases improved over the next 12 hours. The child was awakened the next day, extubated successfully and recovered without complications.
Follow-up Care: A genetics consult and referral to an MH laboratory has been arranged.
Take-home points:
Anesthesiologist was using triggering agents in an office-based setting. He did have dantrolene on stock. This was life-saving.
Anesthesiologist alerted surgical team in a timely fashion.
Ambulance team was not prepared to handle patient with acute MH
Small town ER was not trained in the care of a child with acute MH
Anesthesiologist was willing to participate in transfer of care of patient.
Questions:
1. When providing care for children in an office-based setting can anesthesia providers use general inhalational anesthesia?
Yes
2. Should the medical provider team in an office-based setting doing surgical procedures requiring general anesthetics including succinyl choline receive in-service and training to take care of children and adults during an acute MH episode
Yes
No
3. When transferring care of a patient with acute MH to a more skilled facility setting (e.g. a pediatric intensive care unit), is it appropriate for an individual with anesthesia training to accompany the patient in the ambulance?
Yes
Answers:
1. Yes, anesthesia providers may use triggering agents but they should have in stock dantrolene and the care should include standard of care monitoring that includes exhaled carbon dioxide monitoring and body temperature.
2. In any setting when general anesthesia is being used for procedures, the entire team must have undergone training and also a drill detailing the care of patients with acute MH
3. Yes, this would be ideal and preferred. However, there should be a safe plan in place to take care of other patients that may need ongoing services of the anesthesia provider.
Kumar Belani, MD
Fairview University Medical Center
Minneapolis, MN
